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Wikipedia

Fertilizer

January 06, 2023

"Plant food" redirects here. For the drug term, see Bath salts (drug).

A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced.[1] For most modern agricultural practices, fertilization focuses on three main macro nutrients: nitrogen (N), phosphorus (P), and potassium (K) with occasional addition of supplements like rock flour for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment or hand-tool methods.

A farmer spreading manure to improve soil fertility

Historically fertilization came from natural or organic sources: compost, animal manure, human manure, harvested minerals, crop rotations and byproducts of human-nature industries (i.e. fish processing waste, or bloodmeal from animal slaughter). However, starting in the 19th century, after innovations in plant nutrition, an agricultural industry developed around synthetically created fertilizers. This transition was important in transforming the global food system, allowing for larger-scale industrial agriculture with large crop yields.

Nitrogen-fixing chemical processes such as the Haber process at the beginning of the 20th century, amplified by production capacity created during World War II led to a boom in using nitrogen fertilizers.[2] In the latter half of the 20th century, increased the use of nitrogen fertilizers (800% increase between 1961 and 2019) have been a crucial component of the increased productivity of conventional food systems (more than 30% per capita) as part of the so-called "Green Revolution".[3] The use of artificial and industrially-applied fertilizers has led to a number of environmental impacts, creating water pollution and Eutrophication caused by nutritional runoff, carbon and other emissions from fertilizer production and mining, and contamination and pollution of soil. Various types of sustainable agriculture practices can be implemented to reduce the environmental impact of fertilizer uses alongside other environmental impacts of agriculture.

History

Main article: History of fertilizer
 
Total fertilizer production by type.[4]
 
World population supported with and without synthetic nitrogen fertilizers.[5]
 
Founded in 1812, Mirat, producer of manures and fertilizers, is claimed to be the oldest industrial business in Salamanca (Spain).

Management of soil fertility has preoccupied farmers for thousands of years. Egyptians, Romans, Babylonians, and early Germans are all recorded as using minerals or manure to enhance the productivity of their farms.[1] The science of plant nutrition started well before the work of German chemist Justus von Liebig although his name is most mentioned. Nicolas Théodore de Saussure and scientific colleagues at the time were quick to disprove the simplifications of Justus von Liebig. There was a complex scientific understanding of plant nutrition, where the role of humus and organo-mineral interactions were central, and which was in line with more recent discoveries from 1990 onwards.[6] Prominent scientists on whom Justus von Liebig drew were Carl Ludwig Sprenger and Hermann Hellriegel. In this field, a 'knowledge erosion'[7] took place, partly driven by an intermingling of economics and research.[8] John Bennet Lawes, an English entrepreneur, began to experiment on the effects of various manures on plants growing in pots in 1837, and a year or two later the experiments were extended to crops in the field. One immediate consequence was that in 1842 he patented a manure formed by treating phosphates with sulfuric acid, and thus was the first to create the artificial manure industry. In the succeeding year he enlisted the services of Joseph Henry Gilbert; together they performed crop experiments at the Institute of Arable Crops Research.[9]

The Birkeland–Eyde process was one of the competing industrial processes in the beginning of nitrogen-based fertilizer production.[10] This process was used to fix atmospheric nitrogen (N2) into nitric acid (HNO3), one of several chemical processes generally referred to as nitrogen fixation. The resultant nitric acid was then used as a source of nitrate (NO3−). A factory based on the process was built in Rjukan and Notodden in Norway, combined with the building of large hydroelectric power facilities.[11]

The 1910s and 1920s witnessed the rise of the Haber process and the Ostwald process. The Haber process produces ammonia (NH3) from methane (CH4) (natural gas) gas and molecular nitrogen (N2) from the air. The ammonia from the Haber process is then partially converted into nitric acid (HNO3) in the Ostwald process.[12] After World War II, Nitrogen production plants that had ramped up for war-time bomb manufacturing were pivoted towards agriculture uses.[13] The use of synthetic nitrogen fertilizers has increased steadily in the last 50 years, rising almost 20-fold to the current rate of 100 million tonnes of nitrogen per year.[14]

The development of synthetic nitrogen fertilizer has significantly supported global population growth — it has been estimated that almost half the people on the Earth are currently fed as a result of synthetic nitrogen fertilizer use.[15] The use of phosphate fertilizers has also increased from 9 million tonnes per year in 1960 to 40 million tonnes per year in 2000. A maize crop yielding 6–9 tonnes of grain per hectare (2.5 acres) requires 31–50 kilograms (68–110 lb) of phosphate fertilizer to be applied; soybean crops require about half, as 20–25 kg per hectare.[16] Yara International is the world's largest producer of nitrogen-based fertilizers.[17]

Mechanism

 
Six tomato plants grown with and without nitrate fertilizer on nutrient-poor sand/clay soil. One of the plants in the nutrient-poor soil has died.
 
Inorganic fertilizer use by region[18]

Fertilizers enhance the growth of plants. This goal is met in two ways, the traditional one being additives that provide nutrients. The second mode by which some fertilizers act is to enhance the effectiveness of the soil by modifying its water retention and aeration. This article, like many on fertilizers, emphasises the nutritional aspect. Fertilizers typically provide, in varying proportions:[19]

The nutrients required for healthy plant life are classified according to the elements, but the elements are not used as fertilizers. Instead compounds containing these elements are the basis of fertilizers. The macro-nutrients are consumed in larger quantities and are present in plant tissue in quantities from 0.15% to 6.0% on a dry matter (DM) (0% moisture) basis. Plants are made up of four main elements: hydrogen, oxygen, carbon, and nitrogen. Carbon, hydrogen and oxygen are widely available as water and carbon dioxide. Although nitrogen makes up most of the atmosphere, it is in a form that is unavailable to plants. Nitrogen is the most important fertilizer since nitrogen is present in proteins, DNA and other components (e.g., chlorophyll). To be nutritious to plants, nitrogen must be made available in a "fixed" form. Only some bacteria and their host plants (notably legumes) can fix atmospheric nitrogen (N2) by converting it to ammonia. Phosphate is required for the production of DNA and ATP, the main energy carrier in cells, as well as certain lipids.

Microbiological considerations

Two sets of enzymatic reactions are highly relevant to the efficiency of nitrogen-based fertilizers.

Urease

The first is the hydrolysis (reaction with water) of urea. Many soil bacteria possess the enzyme urease, which catalyzes conversion of urea to ammonium ion (NH4+) and bicarbonate ion (HCO3−).

Ammonia oxidation

Ammonia-oxidizing bacteria (AOB), such as species of Nitrosomonas, oxidize ammonia to nitrite, a process termed nitrification.[20] Nitrite-oxidizing bacteria, especially Nitrobacter, oxidize nitrite to nitrate, which is extremely mobile and is a major cause of eutrophication.

Classification

Fertilizers are classified in several ways. They are classified according to whether they provide a single nutrient (e.g., K, P, or N), in which case they are classified as "straight fertilizers". "multinutrient fertilizers" (or "complex fertilizers") provide two or more nutrients, for example N and P. Fertilizers are also sometimes classified as inorganic (the topic of most of this article) versus organic. Inorganic fertilizers exclude carbon-containing materials except ureas. Organic fertilizers are usually (recycled) plant- or animal-derived matter. Inorganic are sometimes called synthetic fertilizers since various chemical treatments are required for their manufacture.[21]

Single nutrient ("straight") fertilizers

The main nitrogen-based straight fertilizer is ammonia or its solutions. Ammonium nitrate (NH4NO3) is also widely used. Urea is another popular source of nitrogen, having the advantage that it is solid and non-explosive, unlike ammonia and ammonium nitrate, respectively. A few percent of the nitrogen fertilizer market (4% in 2007)[22] has been met by calcium ammonium nitrate (Ca(NO3)2 · NH4 · 10 H2O).

The main straight phosphate fertilizers are the superphosphates. "Single superphosphate" (SSP) consists of 14–18% P2O5, again in the form of Ca(H2PO4)2, but also phosphogypsum (CaSO4 · 2 H2O). Triple superphosphate (TSP) typically consists of 44–48% of P2O5 and no gypsum. A mixture of single superphosphate and triple superphosphate is called double superphosphate. More than 90% of a typical superphosphate fertilizer is water-soluble.

The main potassium-based straight fertilizer is muriate of potash (MOP). Muriate of potash consists of 95–99% KCl, and is typically available as 0-0-60 or 0-0-62 fertilizer.

Multinutrient fertilizers

These fertilizers are common. They consist of two or more nutrient components.

Binary (NP, NK, PK) fertilizers

Major two-component fertilizers provide both nitrogen and phosphorus to the plants. These are called NP fertilizers. The main NP fertilizers are monoammonium phosphate (MAP) and diammonium phosphate (DAP). The active ingredient in MAP is NH4H2PO4. The active ingredient in DAP is (NH4)2HPO4. About 85% of MAP and DAP fertilizers are soluble in water.

NPK fertilizers
Main article: Labeling of fertilizer

NPK fertilizers are three-component fertilizers providing nitrogen, phosphorus, and potassium. There exist two types of NPK fertilizers: compound and blends. Compound NPK fertilizers contain chemically bound ingredients, while blended NPK fertilizers are physical mixtures of single nutrient components.

NPK rating is a rating system describing the amount of nitrogen, phosphorus, and potassium in a fertilizer. NPK ratings consist of three numbers separated by dashes (e.g., 10-10-10 or 16-4-8) describing the chemical content of fertilizers.[23][24] The first number represents the percentage of nitrogen in the product; the second number, P2O5; the third, K2O. Fertilizers do not actually contain P2O5 or K2O, but the system is a conventional shorthand for the amount of the phosphorus (P) or potassium (K) in a fertilizer. A 50-pound (23 kg) bag of fertilizer labeled 16-4-8 contains 8 lb (3.6 kg) of nitrogen (16% of the 50 pounds), an amount of phosphorus equivalent to that in 2 pounds of P2O5 (4% of 50 pounds), and 4 pounds of K2O (8% of 50 pounds). Most fertilizers are labeled according to this N-P-K convention, although Australian convention, following an N-P-K-S system, adds a fourth number for sulfur, and uses elemental values for all values including P and K.[25]

Micronutrients

Micronutrients are consumed in smaller quantities and are present in plant tissue on the order of parts-per-million (ppm), ranging from 0.15 to 400 ppm or less than 0.04% dry matter.[26][27] These elements are often required for enzymes essential to the plant's metabolism. Because these elements enable catalysts (enzymes), their impact far exceeds their weight percentage. Typical micronutrients are boron, zinc, molybdenum, iron, and manganese.[19] These elements are provided as water-soluble salts. Iron presents special problems because it converts to insoluble (bio-unavailable) compounds at moderate soil pH and phosphate concentrations. For this reason, iron is often administered as a chelate complex, e.g., the EDTA or EDDHA derivatives. The micronutrient needs depend on the plant and the environment. For example, sugar beets appear to require boron, and legumes require cobalt,[1] while environmental conditions such as heat or drought make boron less available for plants.[28]

Environment

Synthetic fertilizer used in agriculture has wide-reaching environmental consequences. According to the Intergovernmental Panel on Climate Change (IPCC) Special Report on Climate Change and Land, production of these fertilizers and associated land use practices are drivers of global warming.[3] The use of fertilizer has also led to a number of direct environmental consequences: agricultural runoff which leads to downstream effects like ocean dead zones and waterway contamination, soil microbiome degradation,[29] and accumulation of toxins in ecosystems. Indirect environmental impacts include: the environmental impacts of fracking for natural gas used in the Haber process, the agricultural boom is partially responsible for the rapid growth in human population and large-scale industrial agricultural practices are associated with habitat destruction, pressure on biodiversity and agricultural soil loss.

In order to mitigate environmental and food security concerns, the international community has included food systems in Sustainable Development Goal 2 which focuses on creating a climate-friendly and sustainable food production system.[30] Most policy and regulatory approaches to address these issues focus on pivoting agricultural practices towards sustainable or regenerative agricultural practices: these use less synthetic fertilizers, better soil management (for example no-till agriculture) and more organic fertilizers.

Production

The production of synthetic, or inorganic, fertilizers requires prepared chemicals, whereas organic fertilizers are derived from the organic processes of plants and animals in biological processes using biochemicals.

Nitrogen fertilizers

 
Total nitrogenous fertilizer consumption per region, measured in tonnes of total nutrient per year.

Top users of nitrogen-based fertilizer[31]
Country Total N use
(Mt pa) 		Amt. used for
feed/pasture
(Mt pa)
China 18.7 3.0
India 11.9 —[32]
U.S. 9.1 4.7
France 2.5 1.3
Germany 2.0 1.2
Brazil 1.7 0.7
Canada 1.6 0.9
Turkey 1.5 0.3
UK 1.3 0.9
Mexico 1.3 0.3
Spain 1.2 0.5
Argentina 0.4 0.1

Nitrogen fertilizers are made from ammonia (NH3) produced by the Haber–Bosch process.[22] In this energy-intensive process, natural gas (CH4) usually supplies the hydrogen, and the nitrogen (N2) is derived from the air. This ammonia is used as a feedstock for all other nitrogen fertilizers, such as anhydrous ammonium nitrate (NH4NO3) and urea (CO(NH2)2).

Deposits of sodium nitrate (NaNO3) (Chilean saltpeter) are also found in the Atacama desert in Chile and was one of the original (1830) nitrogen-rich fertilizers used.[33] It is still mined for fertilizer.[34] Nitrates are also produced from ammonia by the Ostwald process.

Phosphate fertilizers

 
An apatite mine in Siilinjärvi, Finland

Phosphate fertilizers are obtained by extraction from phosphate rock, which contains two principal phosphorus-containing minerals, fluorapatite Ca5(PO4)3F (CFA) and hydroxyapatite Ca5(PO4)3OH. These minerals are converted into water-soluble phosphate salts by treatment with sulfuric (H2SO4) or phosphoric acids (H3PO4). The large production of sulfuric acid is primarily motivated by this application.[35] In the nitrophosphate process or Odda process (invented in 1927), phosphate rock with up to a 20% phosphorus (P) content is dissolved with nitric acid (HNO3) to produce a mixture of phosphoric acid (H3PO4) and calcium nitrate (Ca(NO3)2). This mixture can be combined with a potassium fertilizer to produce a compound fertilizer with the three macronutrients N, P and K in easily dissolved form.[36]

Potassium fertilizers

Potash is a mixture of potassium minerals used to make potassium (chemical symbol: K) fertilizers. Potash is soluble in water, so the main effort in producing this nutrient from the ore involves some purification steps; e.g., to remove sodium chloride (NaCl) (common salt). Sometimes potash is referred to as K2O, as a matter of convenience to those describing the potassium content. In fact, potash fertilizers are usually potassium chloride, potassium sulfate, potassium carbonate, or potassium nitrate.[37]

NPK fertilizers

Main article: NPK fertilizer

There are four major routes for manufacturing NPK fertilizers (named for their main ingredients: nitrogen (N), phosphorus (P), and potassium (K)):

  1. steam granulation,
  2. chemical granulation,
  3. compaction,
  4. bulk blending.

The first three processes are used to produce compound NPKs. During steam granulation raw materials are mixed and further granulated using steam as binding agent. Chemical granulation process is based on chemical reactions between liquid raw materials (such as phosphoric acid, sulfuric acid, ammonia) and solid raw materials (such as potassium chloride, recycle material). Compaction implements high pressure to agglomerate dry powder materials. Lastly, bulk blends are produced by mixing straight fertilizers.

Organic fertilizers

Main article: Organic fertilizer
 
Compost bin for small-scale production of organic fertilizer
 
A large commercial compost operation

"Organic fertilizers" can describe those fertilizers with an organic – biologic – origin—that is, fertilizers derived from living or formerly living materials. Organic fertilizers can also describe commercially available and frequently packaged products that strive to follow the expectations and restrictions adopted by "organic agriculture" and "environmentally friendly" gardening – related systems of food and plant production that significantly limit or strictly avoid the use of synthetic fertilizers and pesticides. The "organic fertilizer" products typically contain both some organic materials as well as acceptable additives such as nutritive rock powders, ground sea shells (crab, oyster, etc.), other prepared products such as seed meal or kelp, and cultivated microorganisms and derivatives.

Fertilizers of an organic origin (the first definition) include animal wastes, plant wastes from agriculture, seaweed, compost, and treated sewage sludge (biosolids). Beyond manures, animal sources can include products from the slaughter of animals – bloodmeal, bone meal, feather meal, hides, hoofs, and horns all are typical components.[19] Organically derived materials available to industry such as sewage sludge may not be acceptable components of organic farming and gardening, because of factors ranging from residual contaminants to public perception. On the other hand, marketed "organic fertilizers" may include, and promote, processed organics because the materials have consumer appeal. No matter the definition nor composition, most of these products contain less-concentrated nutrients, and the nutrients are not as easily quantified. They can offer soil-building advantages as well as be appealing to those who are trying to farm / garden more "naturally".[38]

In terms of volume, peat is the most widely used packaged organic soil amendment. It is an immature form of coal and improves the soil by aeration and absorbing water but confers no nutritional value to the plants. It is therefore not a fertilizer as defined in the beginning of the article, but rather an amendment. Coir, (derived from coconut husks), bark, and sawdust when added to soil all act similarly (but not identically) to peat and are also considered organic soil amendments – or texturizers – because of their limited nutritive inputs. Some organic additives can have a reverse effect on nutrients – fresh sawdust can consume soil nutrients as it breaks down, and may lower soil pH – but these same organic texturizers (as well as compost, etc.) may increase the availability of nutrients through improved cation exchange, or through increased growth of microorganisms that in turn increase availability of certain plant nutrients. Organic fertilizers such as composts and manures may be distributed locally without going into industry production, making actual consumption more difficult to quantify.

Application

 
Applying superphosphate fertilizer by hand, New Zealand, 1938

Fertilizers are commonly used for growing all crops, with application rates depending on the soil fertility, usually as measured by a soil test and according to the particular crop. Legumes, for example, fix nitrogen from the atmosphere and generally do not require nitrogen fertilizer.

Liquid vs solid

Fertilizers are applied to crops both as solids and as liquid. About 90% of fertilizers are applied as solids. The most widely used solid inorganic fertilizers are urea, diammonium phosphate and potassium chloride.[39] Solid fertilizer is typically granulated or powdered. Often solids are available as prills, a solid globule. Liquid fertilizers comprise anhydrous ammonia, aqueous solutions of ammonia, aqueous solutions of ammonium nitrate or urea. These concentrated products may be diluted with water to form a concentrated liquid fertilizer (e.g., UAN). Advantages of liquid fertilizer are its more rapid effect and easier coverage.[19] The addition of fertilizer to irrigation water is called "fertigation".[37]

Urea

Main article: urea

Urea is highly soluble in water and is therefore also very suitable for use in fertilizer solutions (in combination with ammonium nitrate: UAN), e.g., in 'foliar feed' fertilizers. For fertilizer use, granules are preferred over prills because of their narrower particle size distribution, which is an advantage for mechanical application.

Urea is usually spread at rates of between 40 and 300 kg/ha (35 to 270 lbs/acre) but rates vary. Smaller applications incur lower losses due to leaching. During summer, urea is often spread just before or during rain to minimize losses from volatilization (a process wherein nitrogen is lost to the atmosphere as ammonia gas).

Because of the high nitrogen concentration in urea, it is very important to achieve an even spread. Drilling must not occur on contact with or close to seed, due to the risk of germination damage. Urea dissolves in water for application as a spray or through irrigation systems.

In grain and cotton crops, urea is often applied at the time of the last cultivation before planting. In high rainfall areas and on sandy soils (where nitrogen can be lost through leaching) and where good in-season rainfall is expected, urea can be side- or top-dressed during the growing season. Top-dressing is also popular on pasture and forage crops. In cultivating sugarcane, urea is side-dressed after planting, and applied to each ratoon crop.

Because it absorbs moisture from the atmosphere, urea is often stored in closed containers.

Overdose or placing urea near seed is harmful.[40]

Slow- and controlled-release fertilizers

This section is an excerpt from Controlled-release fertiliser.[edit]
 
Methylene diurea (MDU) is component of the most popular controlled-release fertilizers.[41]
A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period).[42] Controlled-release fertilizer is also known as controlled-availability fertilizer, delayed-release fertilizer, metered-release fertilizer, or slow-acting fertilizer. Usually CRF refers to nitrogen-based fertilizers. Slow- and controlled-release involve only 0.15% (562,000 tons) of the fertilizer market (1995).

Foliar application

Foliar fertilizers are applied directly to leaves. This method is almost invariably used to apply water-soluble straight nitrogen fertilizers and used especially for high-value crops such as fruits. Urea is the most common foliar fertilizer.[19]

 
Fertilizer burn

Chemicals that affect nitrogen uptake

 
N-Butylthiophosphoryltriamide, an enhanced efficiency fertilizer.

Various chemicals are used to enhance the efficiency of nitrogen-based fertilizers. In this way farmers can limit the polluting effects of nitrogen run-off. Nitrification inhibitors (also known as nitrogen stabilizers) suppress the conversion of ammonia into nitrate, an anion that is more prone to leaching. 1-Carbamoyl-3-methylpyrazole (CMP), dicyandiamide, nitrapyrin (2-chloro-6-trichloromethylpyridine) and 3,4-Dimethylpyrazole phosphate (DMPP) are popular.[43] Urease inhibitors are used to slow the hydrolytic conversion of urea into ammonia, which is prone to evaporation as well as nitrification. The conversion of urea to ammonia catalyzed by enzymes called ureases. A popular inhibitor of ureases is N-(n-butyl)thiophosphoric triamide (NBPT).

Overfertilization

Careful use of fertilization technologies is important because excess nutrients can be detrimental.[44] Fertilizer burn can occur when too much fertilizer is applied, resulting in damage or even death of the plant. Fertilizers vary in their tendency to burn roughly in accordance with their salt index.[45][46]

Statistics

 
Fertilizer use (2018). From FAO's World Food and Agriculture – Statistical Yearbook 2020[47]

Recently nitrogen fertilizers have plateaued in most developed countries. China although has become the largest producer and consumer of nitrogen fertilizers.[48] Africa has little reliance on nitrogen fertilizers.[49] Agricultural and chemical minerals are very important in industrial use of fertilizers, which is valued at approximately $200 billion.[50] Nitrogen has a significant impact in the global mineral use, followed by potash and phosphate. The production of nitrogen has drastically increased since the 1960s. Phosphate and potash have increased in price since the 1960s, which is larger than the consumer price index.[50] Potash is produced in Canada, Russia and Belarus, together making up over half of the world production.[50] Potash production in Canada rose in 2017 and 2018 by 18.6%.[51] Conservative estimates report 30 to 50% of crop yields are attributed to natural or synthetic commercial fertilizers.[37][52] Fertilizer consumption has surpassed the amount of farmland in the United States.[50] Global market value is likely to rise to more than US$185 billion until 2019.[53] The European fertilizer market will grow to earn revenues of approx. €15.3 billion in 2018.[54]

Data on the fertilizer consumption per hectare arable land in 2012 are published by The World Bank.[55] The diagram below shows fertilizer consumption by the European Union (EU) countries as kilograms per hectare (pounds per acre). The total consumption of fertilizer in the EU is 15.9 million tons for 105 million hectare arable land area[56] (or 107 million hectare arable land according to another estimate[57]). This figure equates to 151 kg of fertilizers consumed per ha arable land on average by the EU countries.

 

Environmental effects

 
Runoff of soil and fertilizer during a rain storm

Use of fertilizers are beneficial in providing nutrients to plants although they have some negative environmental effects. The large growing consumption of fertilizers can affect soil, surface water, and groundwater due to dispersion of mineral use.[50]

See also: Environmental impact of agriculture, Human impact on the nitrogen cycle, Nitrogen fertilizer § Problems with inorganic fertilizer, and Nitrogen Cycle
 
Large pile of phosphogypsum waste near Fort Meade, Florida.

For each ton of phosphoric acid produced by the processing of phosphate rock, five tons of waste are generated. This waste takes the form of impure, useless, radioactive solid called phosphogypsum. Estimates range from 100,000,000 and 280,000,000 tons of phosphogypsum waste are produced annually worldwide.[58]

Water

Main article: Eutrophication
 
Red circles show the location and size of many dead zones.

Phosphorus and nitrogen fertilizers when commonly used have major environmental effects. This is due to high rainfalls causing the fertilizers to be washed into waterways.[59][60] Agricultural run-off is a major contributor to the eutrophication of fresh water bodies. For example, in the US, about half of all the lakes are eutrophic. The main contributor to eutrophication is phosphate, which is normally a limiting nutrient; high concentrations promote the growth of cyanobacteria and algae, the demise of which consumes oxygen.[61] Cyanobacteria blooms ('algal blooms') can also produce harmful toxins that can accumulate in the food chain, and can be harmful to humans.[62][63] Fertilizer run-off can be reduced by using weather-optimised fertilization strategies.[60]

The nitrogen-rich compounds found in fertilizer runoff are the primary cause of serious oxygen depletion in many parts of oceans, especially in coastal zones, lakes and rivers. The resulting lack of dissolved oxygen greatly reduces the ability of these areas to sustain oceanic fauna.[64] The number of oceanic dead zones near inhabited coastlines is increasing.[65]

As of 2006, the application of nitrogen fertilizer is being increasingly controlled in northwestern Europe[66] and the United States.[67][68] In cases where eutrophication can be reversed, it may nevertheless take decades[69] and significant soil management[70] before the accumulated nitrates in groundwater can be broken down by natural processes.

Nitrate pollution

Only a fraction of the nitrogen-based fertilizers is converted to plant matter. The remainder accumulates in the soil or is lost as run-off.[71] High application rates of nitrogen-containing fertilizers combined with the high water solubility of nitrate leads to increased runoff into surface water as well as leaching into groundwater, thereby causing groundwater pollution.[72][73][74] The excessive use of nitrogen-containing fertilizers (be they synthetic or natural) is particularly damaging, as much of the nitrogen that is not taken up by plants is transformed into nitrate which is easily leached.[75]

Nitrate levels above 10 mg/L (10 ppm) in groundwater can cause 'blue baby syndrome' (acquired methemoglobinemia).[76] The nutrients, especially nitrates, in fertilizers can cause problems for natural habitats and for human health if they are washed off soil into watercourses or leached through soil into groundwater.[77]

Soil

Acidification

See also: Soil pH and Soil acidification

Nitrogen-containing fertilizers can cause soil acidification when added.[78][79] This may lead to decrease in nutrient availability which may be offset by liming.

Accumulation of toxic elements

Cadmium

The concentration of cadmium in phosphorus-containing fertilizers varies considerably and can be problematic.[80] For example, mono-ammonium phosphate fertilizer may have a cadmium content of as low as 0.14 mg/kg or as high as 50.9 mg/kg.[81] The phosphate rock used in their manufacture can contain as much as 188 mg/kg cadmium[82] (examples are deposits on Nauru[83] and the Christmas islands[84]). Continuous use of high-cadmium fertilizer can contaminate soil (as shown in New Zealand)[85] and plants.[86] Limits to the cadmium content of phosphate fertilizers has been considered by the European Commission.[87][88][89] Producers of phosphorus-containing fertilizers now select phosphate rock based on the cadmium content.[61]

Fluoride

Phosphate rocks contain high levels of fluoride. Consequently, the widespread use of phosphate fertilizers has increased soil fluoride concentrations.[86] It has been found that food contamination from fertilizer is of little concern as plants accumulate little fluoride from the soil; of greater concern is the possibility of fluoride toxicity to livestock that ingest contaminated soils.[90][91] Also of possible concern are the effects of fluoride on soil microorganisms.[90][91][92]

Radioactive elements

The radioactive content of the fertilizers varies considerably and depends both on their concentrations in the parent mineral and on the fertilizer production process.[86][93] Uranium-238 concentrations can range from 7 to 100 pCi/g (picocuries per gram) in phosphate rock[94] and from 1 to 67 pCi/g in phosphate fertilizers.[95][96][97] Where high annual rates of phosphorus fertilizer are used, this can result in uranium-238 concentrations in soils and drainage waters that are several times greater than are normally present.[96][98] However, the impact of these increases on the risk to human health from radinuclide contamination of foods is very small (less than 0.05 mSv/y).[96][99][100]

Other metals

Steel industry wastes, recycled into fertilizers for their high levels of zinc (essential to plant growth), wastes can include the following toxic metals: lead[101] arsenic, cadmium,[101] chromium, and nickel. The most common toxic elements in this type of fertilizer are mercury, lead, and arsenic.[102][103][104] These potentially harmful impurities can be removed; however, this significantly increases cost. Highly pure fertilizers are widely available and perhaps best known as the highly water-soluble fertilizers containing blue dyes used around households, such as Miracle-Gro. These highly water-soluble fertilizers are used in the plant nursery business and are available in larger packages at significantly less cost than retail quantities. Some inexpensive retail granular garden fertilizers are made with high purity ingredients.

Trace mineral depletion

Attention has been addressed to the decreasing concentrations of elements such as iron, zinc, copper and magnesium in many foods over the last 50–60 years.[105][106] Intensive farming practices, including the use of synthetic fertilizers are frequently suggested as reasons for these declines and organic farming is often suggested as a solution.[106] Although improved crop yields resulting from NPK fertilizers are known to dilute the concentrations of other nutrients in plants,[105][107] much of the measured decline can be attributed to the use of progressively higher-yielding crop varieties that produce foods with lower mineral concentrations than their less-productive ancestors.[105][108][109] It is, therefore, unlikely that organic farming or reduced use of fertilizers will solve the problem; foods with high nutrient density are posited to be achieved using older, lower-yielding varieties or the development of new high-yield, nutrient-dense varieties.[105][110]

Fertilizers are, in fact, more likely to solve trace mineral deficiency problems than cause them: In Western Australia deficiencies of zinc, copper, manganese, iron and molybdenum were identified as limiting the growth of broad-acre crops and pastures in the 1940s and 1950s.[111] Soils in Western Australia are very old, highly weathered and deficient in many of the major nutrients and trace elements.[111] Since this time these trace elements are routinely added to fertilizers used in agriculture in this state.[111] Many other soils around the world are deficient in zinc, leading to deficiency in both plants and humans, and zinc fertilizers are widely used to solve this problem.[112]

Changes in soil biology

Further information: soil biology

High levels of fertilizer may cause the breakdown of the symbiotic relationships between plant roots and mycorrhizal fungi.[113]

Energy consumption and sustainability

In the US in 2004, 317 billion cubic feet of natural gas were consumed in the industrial production of ammonia, less than 1.5% of total U.S. annual consumption of natural gas.[114] A 2002 report suggested that the production of ammonia consumes about 5% of global natural gas consumption, which is somewhat under 2% of world energy production.[115]

Ammonia is produced from natural gas and air.[116] The cost of natural gas makes up about 90% of the cost of producing ammonia.[117] The increase in price of natural gases over the past decade, along with other factors such as increasing demand, have contributed to an increase in fertilizer price.[118]

Contribution to climate change

See also: Greenhouse gas emissions from agriculture

The greenhouse gases carbon dioxide, methane and nitrous oxide are produced during the manufacture of nitrogen fertilizer. CO2 is estimated as over 1% of global CO2 emissions.[119] Nitrogen fertilizer can be converted by soil bacteria to nitrous oxide, a greenhouse gas.[120] Nitrous oxide emissions by humans, most of which are from fertilizer, between 2007 and 2016 have been estimated at 7 million tonnes per year,[121] which is incompatible with limiting global warming to below 2 °C.[122]

Atmosphere

 
Global methane concentrations (surface and atmospheric) for 2005; note distinct plumes

Through the increasing use of nitrogen fertilizer, which was used at a rate of about 110 million tons (of N) per year in 2012,[123][124] adding to the already existing amount of reactive nitrogen, nitrous oxide (N2O) has become the third most important greenhouse gas after carbon dioxide and methane. It has a global warming potential 296 times larger than an equal mass of carbon dioxide and it also contributes to stratospheric ozone depletion.[125] By changing processes and procedures, it is possible to mitigate some, but not all, of these effects on anthropogenic climate change.[126]

Methane emissions from crop fields (notably rice paddy fields) are increased by the application of ammonium-based fertilizers. These emissions contribute to global climate change as methane is a potent greenhouse gas.[127][128]

Policy

Regulation

In Europe, problems with high nitrate concentrations in runoff are being addressed by the European Union's Nitrates Directive.[129] Within Britain, farmers are encouraged to manage their land more sustainably in 'catchment-sensitive farming'.[130] In the US, high concentrations of nitrate and phosphorus in runoff and drainage water are classified as nonpoint source pollutants due to their diffuse origin; this pollution is regulated at the state level.[131] Oregon and Washington, both in the United States, have fertilizer registration programs with on-line databases listing chemical analyses of fertilizers.[132][133]

In China, regulations have been implemented to control the use of N fertilizers in farming. In 2008, Chinese governments began to partially withdraw fertilizer subsidies, including subsidies to fertilizer transportation and to electricity and natural gas use in the industry. In consequence, the price of fertilizer has gone up and large-scale farms have begun to use less fertilizer. If large-scale farms keep reducing their use of fertilizer subsidies, they have no choice but to optimize the fertilizer they have which would therefore gain an increase in both grain yield and profit.[134]

In March 2022, the United States Department of Agriculture announced a new $250M grant to promote American fertilizer production. Part of the Commodity Credit Corporation, the grant program will support fertilizer production that is independent of dominant fertilizer suppliers, made in America, and utilizing innovative production techniques to jumpstart future competition.[135]

Two types of agricultural management practices include organic agriculture and conventional agriculture. The former encourages soil fertility using local resources to maximize efficiency. Organic agriculture avoids synthetic agrochemicals. Conventional agriculture uses all the components that organic agriculture does not use.[136]

See also

References

  1. ^ a b c Scherer, Heinrich W.; Mengel, Konrad; Kluge, Günter; Severin, Karl (2009). "Fertilizers, 1. General". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a10_323.pub3.
  2. ^ "Fritz Haber". Science History Institute. 1 June 2016. Retrieved 16 December 2022.
  3. ^ a b Mbow et al. 2019.
  4. ^ "Total fertilizer production by nutrient". Our World in Data. Retrieved 7 March 2020.
  5. ^ "World population with and without synthetic nitrogen fertilizers". Our World in Data. Retrieved 5 March 2020.
  6. ^ Visser, Jozef (20 November 2019), Larramendy, Marcelo; Soloneski, Sonia (eds.), "Opening History: Gaining Perspectives", Organic Fertilizers - History, Production and Applications, IntechOpen, doi:10.5772/intechopen.86185, ISBN 978-1-78985-147-2, retrieved 13 April 2021
  7. ^ Uekötter, Frank (2010). Die Wahrheit ist auf dem Feld: Eine Wissensgeschichte der deutschen Landwirtschaft. Vandenhoeck & Ruprecht. ISBN 978-3-5253-1705-1.
  8. ^ Uekötter, Frank (2014). "Why Panaceas Work: Recasting Science, Knowledge, and Fertilizer Interests in German Agriculture". Agricultural History. 88 (1): 68–86. doi:10.3098/ah.2014.88.1.68. ISSN 0002-1482. JSTOR 10.3098/ah.2014.88.1.68.
  9. ^   This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Lawes, Sir John Bennet". Encyclopædia Britannica (11th ed.). Cambridge University Press.
  10. ^ Aaron John Ihde (1984). The development of modern chemistry. Courier Dover Publications. p. 678. ISBN 978-0-486-64235-2.
  11. ^ G. J. Leigh (2004). The world's greatest fix: a history of nitrogen and agriculture. Oxford University Press US. pp. 134–139. ISBN 978-0-19-516582-1.
  12. ^ Trevor Illtyd Williams; Thomas Kingston Derry (1982). A short history of twentieth-century technology c. 1900-c. 1950. Oxford University Press. pp. 134–135. ISBN 978-0-19-858159-8.
  13. ^ Philpott, Tom. "A Brief History of Our Deadly Addiction to Nitrogen Fertilizer". Mother Jones. Retrieved 24 March 2021.
  14. ^ Glass, Anthony (September 2003). "Nitrogen Use Efficiency of Crop Plants: Physiological Constraints upon Nitrogen Absorption". Critical Reviews in Plant Sciences. 22 (5): 453–470. doi:10.1080/713989757.
  15. ^ Erisman, Jan Willem; MA Sutton, J Galloway, Z Klimont, W Winiwarter (October 2008). . Nature Geoscience. 1 (10): 636–639. Bibcode:2008NatGe...1..636E. doi:10.1038/ngeo325. S2CID 94880859. Archived from the original on 23 July 2010. Retrieved 22 October 2010.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  16. ^ Vance, Carroll P; Uhde-Stone & Allan (2003). "Phosphorus acquisition and use: critical adaptations by plants for securing a non renewable resource". New Phytologist. 157 (3): 423–447. doi:10.1046/j.1469-8137.2003.00695.x. JSTOR 1514050. PMID 33873400. S2CID 53490640.
  17. ^ "Mergers in the fertiliser industry". The Economist. 18 February 2010. Retrieved 21 February 2010.
  18. ^ World Food and Agriculture – Statistical Yearbook 2021. www.fao.org. 2021. doi:10.4060/cb4477en. ISBN 978-92-5-134332-6. S2CID 240163091. Retrieved 10 December 2021.{{cite book}}: CS1 maint: url-status (link)
  19. ^ a b c d e Dittmar, Heinrich; Drach, Manfred; Vosskamp, Ralf; Trenkel, Martin E.; Gutser, Reinhold; Steffens, Günter (2009). "Fertilizers, 2. Types". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.n10_n01.
  20. ^ Marsh KL, Sims GK, Mulvaney RL (2005). "Availability of urea to autotrophic ammonia-oxidizing bacteria as related to the fate of 14C- and 15N-labeled urea added to soil". Biology and Fertility of Soils. 42 (2): 137–145. doi:10.1007/s00374-005-0004-2. S2CID 6245255.
  21. ^ J. Benton Jones, Jr. "Inorganic Chemical Fertilisers and Their Properties" in Plant Nutrition and Soil Fertility Manual, Second Edition. CRC Press, 2012. ISBN 978-1-4398-1609-7. eBook ISBN 978-1-4398-1610-3.
  22. ^ a b Smil, Vaclav (2004). Enriching the Earth. Massachusetts Institute of Technology. p. 135. ISBN 978-0-262-69313-4.
  23. ^ "Summary of State Fertilizer Laws" (PDF). EPA. Archived (PDF) from the original on 9 October 2022. Retrieved 14 March 2013.
  24. ^ "Label Requirements of specialty and other bagged fertilizers". Michigan Department of Agriculture and Rural Development. Retrieved 14 March 2013.
  25. ^ (PDF). Australian Government Department of Agriculture, Fisheries and Forestry. Archived from the original (PDF) on 28 February 2015. Retrieved 14 March 2013.
  26. ^ "AESL Plant Analysis Handbook – Nutrient Content of Plant". Aesl.ces.uga.edu. Retrieved 11 September 2015.
  27. ^ H.A. Mills; J.B. Jones Jr. (1996). Plant Analysis Handbook II: A Practical Sampling, Preparation, Analysis, and Interpretation Guide. ISBN 978-1-878148-05-6.
  28. ^ "Boron Deficiency".
  29. ^ Chen, Huaihai; Yang, Zamin K.; Yip, Dan; Morris, Reese H.; Lebreux, Steven J.; Cregger, Melissa A.; Klingeman, Dawn M.; Hui, Dafeng; Hettich, Robert L.; Wilhelm, Steven W.; Wang, Gangsheng (18 June 2019). "One-time nitrogen fertilization shifts switchgrass soil microbiomes within a context of larger spatial and temporal variation". PLOS ONE. 14 (6): e0211310. Bibcode:2019PLoSO..1411310C. doi:10.1371/journal.pone.0211310. ISSN 1932-6203. PMC 6581249. PMID 31211785.
  30. ^ United Nations (2017) Resolution adopted by the General Assembly on 6 July 2017, Work of the Statistical Commission pertaining to the 2030 Agenda for Sustainable Development (A/RES/71/313)
  31. ^ . Retrieved 29 June 2009. United Nations Food and Agriculture Organization.
  32. ^ "Production & Inputs | Government of India, Department of Fertilizers, Ministry of Chemicals and Fertilizers".
  33. ^ . ams.usda.gov. Archived from the original on 14 July 2014. Retrieved 6 July 2014.
  34. ^ . sqm.com. Archived from the original on 14 July 2014. Retrieved 6 July 2014.
  35. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  36. ^ EFMA (2000). (PDF). fertilizerseurope.com. European Fertilizer Manufacturers' Association. Archived from the original (PDF) on 29 July 2014. Retrieved 28 June 2014.
  37. ^ a b c Vasant Gowariker, V. N. Krishnamurthy, Sudha Gowariker, Manik Dhanorkar, Kalyani Paranjape "The Fertilizer Encyclopedia" 2009, John Wiley & Sons. ISBN 978-0-470-41034-9. Online ISBN 978-0-470-43177-1. doi:10.1002/9780470431771
  38. ^ Haynes, R.J, R. Naidu (1998). "Influence of lime, fertilizer and manure applications on soil organic matter content and soil physical conditions: a review". Nutrient Cycling in Agroecosystems. 51 (2): 123–137. doi:10.1023/A:1009738307837. S2CID 20113235 – via Springer Link.
  39. ^ "About Fertilizers Home Page". fertilizer.org. International Fertilizer Association. Retrieved 19 December 2017.
  40. ^ Mikkelsen, R.L. (2007). (PDF). Better Crops. 91 (3): 6–7. Archived from the original (PDF) on 22 December 2015. Retrieved 2 May 2015.
  41. ^ Dittmar, Heinrich; Drach, Manfred; Vosskamp, Ralf; Trenkel, Martin E.; Gutser, Reinhold; Steffens, Günter (2009). "Fertilizers, 2. Types". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.n10_n01.
  42. ^ Gregorich, Edward G.; Turchenek, L. W.; Carter, M. R.; Angers, Denis A., eds. (2001). Soil and Environmental Science Dictionary. CRC Press. p. 132. ISBN 978-0-8493-3115-2. LCCN 2001025292. Retrieved 9 December 2011.
  43. ^ Yang, Ming; Fang, Yunting; Sun, Di; Shi, Yuanliang (2016). "Efficiency of two nitrification inhibitors (dicyandiamide and 3, 4-dimethypyrazole phosphate) on soil nitrogen transformations and plant productivity: a meta-analysis". Scientific Reports. 6 (1): 22075. Bibcode:2016NatSR...622075Y. doi:10.1038/srep22075. ISSN 2045-2322. PMC 4763264. PMID 26902689.
  44. ^ . Hubcap.clemson.edu. Archived from the original on 29 June 2012. Retrieved 17 June 2012.
  45. ^ Garrett, Howard (2014). Organic Lawn Care: Growing Grass the Natural Way. University of Texas Press. pp. 55–56. ISBN 978-0-292-72849-3.
  46. ^ (PDF). Archived from the original (PDF) on 28 May 2013. Retrieved 22 July 2012.
  47. ^ World Food and Agriculture – Statistical Yearbook 2020. Rome: FAO. 2020. doi:10.4060/cb1329en. ISBN 978-92-5-133394-5. S2CID 242794287.
  48. ^ Smil, Vaclav (2015). Making the Modern World: Materials and Dematerialization. United Kingdom: John Wiley & Sons. ISBN 978-1-119-94253-5.
  49. ^ Smil, Vaclav (2012). Harvesting the Biosphere: What We Have Taken From Nature. Massachusetts Institute of Technology. ISBN 978-0-262-01856-2.
  50. ^ a b c d e Kesler and Simon, Stephen and Simon (2015). Mineral Resources, Economics and the Environment. Cambridge. ISBN 978-1-107-07491-0.
  51. ^ "Industry Stats – Fertilizer Canada". Fertilizer Canada. Retrieved 28 March 2018.
  52. ^ Stewart, W.M.; Dibb, D.W.; Johnston, A.E.; Smyth, T.J. (2005). "The Contribution of Commercial Fertilizer Nutrients to Food Production". Agronomy Journal. 97: 1–6. doi:10.2134/agronj2005.0001.
  53. ^ Ceresana, Market Study Fertilizers – World, May 2013,
  54. ^ "Market Study Fertilizers – Europe". Ceresana.com.
  55. ^ "Fertilizer consumption (Kilograms per hectare of arable land) | Data".
  56. ^ . Archived from the original on 6 October 2014. Retrieved 19 October 2011.
  57. ^ Arable land
  58. ^ Tayibi, Hanan; Choura, Mohamed; López, Félix A.; Alguacil, Francisco J.; López-Delgado, Aurora (2009). "Environmental Impact and Management of Phosphogypsum". Journal of Environmental Management. 90 (8): 2377–2386. doi:10.1016/j.jenvman.2009.03.007. hdl:10261/45241. PMID 19406560.
  59. ^ "Environmental impact of nitrogen and phosphorus fertilisers in high rainfall areas". agric.wa.gov.au. Retrieved 9 April 2018.
  60. ^ a b McKay Fletcher, D. M.; Ruiz, S. A.; Dias, T.; Chadwick, D. R.; Jones, D. L.; Roose, T. (20 February 2021). "Precipitation-optimised targeting of nitrogen fertilisers in a model maize cropping system". Science of the Total Environment. 756: 144051. Bibcode:2021ScTEn.756n4051M. doi:10.1016/j.scitotenv.2020.144051. ISSN 0048-9697. PMID 33280884. S2CID 227522409.
  61. ^ a b Wilfried Werner "Fertilizers, 6. Environmental Aspects" Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim.doi:10.1002/14356007.n10_n05
  62. ^ . Archived from the original on 5 August 2014. Retrieved 5 August 2014.
  63. ^ Schmidt, JR; Shaskus, M; Estenik, JF; Oesch, C; Khidekel, R; Boyer, GL (2013). "Variations in the microcystin content of different fish species collected from a eutrophic lake". Toxins (Basel). 5 (5): 992–1009. doi:10.3390/toxins5050992. PMC 3709275. PMID 23676698.
  64. ^ "Rapid Growth Found in Oxygen-Starved Ocean ‘Dead Zones’", NY Times, 14 August 2008
  65. ^ John Heilprin, Associated Press. . Dsc.discovery.com. Archived from the original on 18 June 2010. Retrieved 25 August 2010.
  66. ^ Van Grinsven, H. J. M.; Ten Berge, H. F. M.; Dalgaard, T.; Fraters, B.; Durand, P.; Hart, A.; ... & Willems, W. J. (2012). "Management, regulation and environmental impacts of nitrogen fertilization in northwestern Europe under the Nitrates Directive; a benchmark study". Biogeosciences. 9 (12): 5143–5160. Bibcode:2012BGeo....9.5143V. doi:10.5194/bg-9-5143-2012.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  67. ^ . cals.ncsu.edu. Archived from the original on 23 September 2015. Retrieved 3 July 2014.
  68. ^ State-EPA Nutrient Innovations Task Group (2009). "An Urgent Call to Action – Report of the State-EPA Nutrient Innovations Task Group" (PDF). epa.gov. Archived (PDF) from the original on 9 October 2022. Retrieved 3 July 2014.
  69. ^ "Study shows eutrophic lakes may not recover for a millennium". news.wisc.edu. Retrieved 3 November 2022.
  70. ^ Wilkinson, Grace M. (1 January 2017), "Eutrophication of Freshwater and Coastal Ecosystems", in Abraham, Martin A. (ed.), Encyclopedia of Sustainable Technologies, Oxford: Elsevier, pp. 145–152, doi:10.1016/b978-0-12-409548-9.10160-5, ISBN 978-0-12-804792-7, retrieved 3 November 2022
  71. ^ Callisto, Marcos; Molozzi, Joseline; Barbosa, José Lucena Etham (2014). Eutrophication of Lakes. Eutrophication: Causes, Consequences and Control. pp. 55–71. doi:10.1007/978-94-007-7814-6_5. ISBN 978-94-007-7813-9.
  72. ^ C. J. Rosen; B. P. Horgan (9 January 2009). . Extension.umn.edu. Archived from the original on 10 March 2014. Retrieved 25 August 2010.
  73. ^ Bijay-Singh; Yadvinder-Singh; Sekhon, G.S. (1995). "Fertilizer-N use efficiency and nitrate pollution of groundwater in developing countries". Journal of Contaminant Hydrology. 20 (3–4): 167–184. Bibcode:1995JCHyd..20..167S. doi:10.1016/0169-7722(95)00067-4.
  74. ^ . Nofa.org. 25 February 2004. Archived from the original on 24 March 2004. Retrieved 25 August 2010.
  75. ^ Jackson, Louise E.; Burger, Martin; Cavagnaro, Timothy R. (2008). "Roots, Nitrogen Transformations, and Ecosystem Services". Annual Review of Plant Biology. 59: 341–363. doi:10.1146/annurev.arplant.59.032607.092932. PMID 18444903.
  76. ^ Knobeloch, L; Salna, B; Hogan, A; Postle, J; Anderson, H (2000). "Blue Babies and Nitrate-Contaminated Well Water". Environ. Health Perspect. 108 (7): 675–8. doi:10.1289/ehp.00108675. PMC 1638204. PMID 10903623.
  77. ^ Nitrogen and Water
  78. ^ Schindler, D. W.; Hecky, R. E. (2009). "Eutrophication: More Nitrogen Data Needed". Science. 324 (5928): 721–722. Bibcode:2009Sci...324..721S. doi:10.1126/science.324_721b. PMID 19423798.
  79. ^ Penn, C. J.; Bryant, R. B. (2008). "Phosphorus Solubility in Response to Acidification of Dairy Manure Amended Soils". Soil Science Society of America Journal. 72 (1): 238. Bibcode:2008SSASJ..72..238P. doi:10.2136/sssaj2007.0071N.
  80. ^ McLaughlin, M. J.; Tiller, K. G.; Naidu, R.; Stevens, D. P. (1996). "Review: the behaviour and environmental impact of contaminants in fertilizers". Soil Research. 34: 1–54. doi:10.1071/sr9960001.
  81. ^ Lugon-Moulin, N.; Ryan, L.; Donini, P.; Rossi, L. (2006). "Cadmium content of phosphate fertilizers used for tobacco production" (PDF). Agron. Sustain. Dev. 26 (3): 151–155. doi:10.1051/agro:2006010. S2CID 13996565. Archived (PDF) from the original on 9 October 2022. Retrieved 27 June 2014.
  82. ^ Zapata, F.; Roy, R.N. (2004). "Use of Phosphate Rocks for Sustainable Agriculture: Secondary nutrients, micronutrients, liming effect and hazardous elements associated with phosphate rock use". fao.org. FAO. Retrieved 27 June 2014.
  83. ^ Syers JK, Mackay AD, Brown MW, Currie CD (1986). "Chemical and physical characteristics of phosphate rock materials of varying reactivity". J Sci Food Agric. 37 (11): 1057–1064. doi:10.1002/jsfa.2740371102.
  84. ^ Trueman NA (1965). "The phosphate, volcanic and carbonate rocks of Christmas Island (Indian Ocean)". J Geol Soc Aust. 12 (2): 261–286. Bibcode:1965AuJES..12..261T. doi:10.1080/00167616508728596.
  85. ^ Taylor MD (1997). "Accumulation of Cadmium derived from fertilizers in New Zealand soils". Science of the Total Environment. 208 (1–2): 123–126. Bibcode:1997ScTEn.208..123T. doi:10.1016/S0048-9697(97)00273-8. PMID 9496656.
  86. ^ a b c Chaney, R.L. (2012). Food safety issues for mineral and organic fertilizers. Advances in Agronomy. Vol. 117. pp. 51–99. doi:10.1016/b978-0-12-394278-4.00002-7. ISBN 9780123942784.
  87. ^ Oosterhuis, F.H.; Brouwer, F.M.; Wijnants, H.J. (2000). "A possible EU wide charge on cadmium in phosphate fertilisers: Economic and environmental implications" (PDF). dare.ubvu.vu.nl. Archived (PDF) from the original on 9 October 2022. Retrieved 27 June 2014.
  88. ^ Fertilizers Europe (2014). (PDF). fertilizerseurope.com. Archived from the original (PDF) on 8 August 2014. Retrieved 27 June 2014.
  89. ^ Wates, J. (2014). "Revision of the EU fertilizer regulation and cadmium content of fertilisers". iatp.org. Retrieved 27 June 2014.
  90. ^ a b Loganathan, P.; Hedley, M.J.; Grace, N.D. (2008). Pasture soils contaminated with fertilizer-derived cadmium and fluorine: livestock effects. Reviews of Environmental Contamination and Toxicology. Vol. 192. pp. 29–66. doi:10.1007/978-0-387-71724-1_2. ISBN 978-0-387-71723-4. PMID 18020303.
  91. ^ a b Cronin, S. J.; Manoharan, V.; Hedley, M. J.; Loganathan, P. (2000). "Fluoride: A review of its fate, bioavailability, and risks of fluorosis in grazed‐pasture systems in New Zealand". New Zealand Journal of Agricultural Research. 43 (3): 295–3214. doi:10.1080/00288233.2000.9513430.
  92. ^ Wilke, B.M. (1987). "Fluoride-induced changes in chemical properties and microbial activity of mull, moder and mor soils". Biology and Fertility of Soils. 5: 49–55. doi:10.1007/BF00264346. S2CID 1225884.
  93. ^ Mortvedt, JJ; Beaton, JD. . Archived from the original on 26 July 2014. Retrieved 16 July 2014.
  94. ^ "TENORM: Fertilizer and Fertilizer Production Wastes". US EPA. 2016. Retrieved 30 August 2017.
  95. ^ Khater, A. E. M. (2008). (PDF). radioecology.info. Archived from the original (PDF) on 24 July 2014. Retrieved 17 July 2014.
  96. ^ a b c NCRP (1987). Radiation Exposure of the U.S. Population from Consumer Products and Miscellaneous Sources. National Council on Radiation Protection and Measurements. pp. 29–32. Retrieved 17 July 2014.[permanent dead link]
  97. ^ Hussein EM (1994). "Radioactivity of phosphate ore, superphosphate, and phosphogypsum in Abu-zaabal phosphate". Health Physics. 67 (3): 280–282. doi:10.1097/00004032-199409000-00010. PMID 8056596.
  98. ^ Barisic D, Lulic S, Miletic P (1992). "Radium and uranium in phosphate fertilizers and their impact on the radioactivity of waters". Water Research. 26 (5): 607–611. doi:10.1016/0043-1354(92)90234-U.
  99. ^ Hanlon, E. A. (2012). . edis.ifas.ufl.edu. University of Florida. Archived from the original on 25 July 2014. Retrieved 17 July 2014.
  100. ^ Sharpley, A. N.; Menzel, R. G. (1987). The impact of soil and fertilizer phosphorus on the environment. Advances in Agronomy. Vol. 41. pp. 297–324. doi:10.1016/s0065-2113(08)60807-x. ISBN 9780120007417. S2CID 83005521.
  101. ^ a b Wilson, Duff (3 July 1997). "Business | Fear in the Fields – How Hazardous Wastes Become Fertilizer – Spreading Heavy Metals on Farmland Is Perfectly Legal, But Little Research Has Been Done To Find Out Whether It's Safe | Seattle Times Newspaper". Community.seattletimes.nwsource.com. Retrieved 25 August 2010.
  102. ^ . Pirg.org. 3 July 1997. Archived from the original on 26 November 2010. Retrieved 25 August 2010.
  103. ^ mindfully.org. . Mindfully.org. Archived from the original on 11 January 2002. Retrieved 25 August 2010.
  104. ^ Zapata, F; Roy, RN (2004). Use of phosphate rocks for sustainable agriculture (PDF). Rome: FAO. p. 82. Retrieved 16 July 2014.[permanent dead link]
  105. ^ a b c d Davis, D.R.; Epp, M.D.; Riordan, H.D. (2004). "Changes in USDA Food Composition Data for 43 Garden Crops, 1950 to 1999". Journal of the American College of Nutrition. 23 (6): 669–682. doi:10.1080/07315724.2004.10719409. PMID 15637215. S2CID 13595345.
  106. ^ a b Thomas, D. (2007). "The mineral depletion of foods available to us as a nation (1940–2002) – A Review of the 6th Edition of McCance and Widdowson". Nutrition and Health. 19 (1–2): 21–55. doi:10.1177/026010600701900205. PMID 18309763. S2CID 372456.
  107. ^ Jarrell, W.M.; Beverly, R.B. (1981). The Dilution Effect in Plant Nutrition Studies. Advances in Agronomy. Vol. 34. pp. 197–224. doi:10.1016/s0065-2113(08)60887-1. ISBN 9780120007349.
  108. ^ Fan, M. S.; Zhao, F. J.; Fairweather-Tait, S. J.; Poulton, P. R.; Dunham, S. J.; McGrath, S. P. (2008). "Evidence of decreasing mineral density in wheat grain over the last 160 years". Journal of Trace Elements in Medicine and Biology. 22 (4): 315–324. doi:10.1016/j.jtemb.2008.07.002. PMID 19013359.
  109. ^ Zhao, F. J.; Su, Y. H.; Dunham, S. J.; Rakszegi, M.; Bedo, Z.; McGrath, S. P.; Shewry, P. R. (2009). "Variation in mineral micronutrient concentrations in grain of wheat lines of diverse origin". Journal of Cereal Science. 49 (2): 290–295. doi:10.1016/j.jcs.2008.11.007.
  110. ^ Saltzman, A.; Birol, E.; Bouis, H. E.; Boy, E.; De Moura, F.F.; Islam, Y.; Pfeiffer, W. H. (2013). "Biofortification: progress toward a more nourishing future". Global Food Security. 2: 9–17. doi:10.1016/j.gfs.2012.12.003.
  111. ^ a b c Moore, Geoff (2001). Soilguide – A handbook for understanding and managing agricultural soils. Perth, Western Australia: Agriculture Western Australia. pp. 161–207. ISBN 978-0-7307-0057-9.
  112. ^ "Zinc in Soils and Crop Nutrition". Scribd.com. 25 August 2010. Retrieved 17 June 2012.
  113. ^ Carroll and Salt, Steven B. and Steven D. (2004). Ecology for Gardeners. Cambridge: Timber Press. ISBN 978-0-88192-611-8.
  114. ^ Aleksander Abram; D. Lynn Forster (2005). "A Primer on Ammonia, Nitrogen Fertilizers, and Natural Gas Markets". Department of Agricultural, Environmental, and Development Economics, Ohio State University: 38. {{cite journal}}: Cite journal requires |journal= (help)
  115. ^ IFA – Statistics – Fertilizer Indicators – Details – Raw material reserves, (2002–10) 24 April 2008 at the Wayback Machine
  116. ^ Appl, Max (2000). "Ammonia, 2. Production Processes". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim, Germany: Wiley-VCH. pp. 139–225. doi:10.1002/14356007.o02_o11. ISBN 978-3-527-30673-2.
  117. ^ Sawyer JE (2001). "Natural gas prices affect nitrogen fertilizer costs". IC-486. 1: 8.
  118. ^ . Archived from the original on 6 March 2010.
  119. ^ "Green Ammonia and the Electrification of the Haber–Bosch Process Reduce Carbon Emissions". guidehouseinsights.com. Retrieved 6 March 2022.
  120. ^ "How Fertilizer Is Making Climate Change Worse". BloombergQuint. Retrieved 25 March 2021.
  121. ^ Tian, Hanqin; Xu, Rongting; Canadell, Josep G.; Thompson, Rona L.; Winiwarter, Wilfried; Suntharalingam, Parvadha; Davidson, Eric A.; Ciais, Philippe; Jackson, Robert B.; Janssens-Maenhout, Greet; Prather, Michael J. (October 2020). . Nature. 586 (7828): 248–256. Bibcode:2020Natur.586..248T. doi:10.1038/s41586-020-2780-0. ISSN 1476-4687. PMID 33028999. S2CID 222217027. Archived from the original on 13 October 2020. Alt URL
  122. ^ "Nitrogen fertiliser use could 'threaten global climate goals'". Carbon Brief. 7 October 2020. Retrieved 25 March 2021.
  123. ^ FAO (2012). (PDF). Rome: Food and Agriculture Organization of the United Nations. p. 13. Archived from the original (PDF) on 18 May 2017. Retrieved 3 July 2014.
  124. ^ Gruber, N; Galloway, JN (2008). "An Earth-system perspective of the global nitrogen cycle". Nature. 451 (7176): 293–296. Bibcode:2008Natur.451..293G. doi:10.1038/nature06592. PMID 18202647.
  125. ^ "Human alteration of the nitrogen cycle, threats, benefits and opportunities" 14 January 2009 at the Wayback Machine UNESCO – SCOPE Policy briefs, April 2007
  126. ^ Roy, R. N.; Misra, R. V.; Montanez, A. (2002). (PDF). Ambio: A Journal of the Human Environment. 31 (2): 177–183. doi:10.1579/0044-7447-31.2.177. PMID 12078007. S2CID 905322. Archived from the original (PDF) on 24 September 2015. Retrieved 3 July 2014.
  127. ^ Bodelier, Paul, L.E.; Peter Roslev3, Thilo Henckel1 & Peter Frenzel1 (November 1999). "Stimulation by ammonium-based fertilizers of methane oxidation in soil around rice roots". Nature. 403 (6768): 421–424. Bibcode:2000Natur.403..421B. doi:10.1038/35000193. PMID 10667792. S2CID 4351801.
  128. ^ Banger, K.; Tian, H.; Lu, C. (2012). "Do nitrogen fertilizers stimulate or inhibit methane emissions from rice fields?". Global Change Biology. 18 (10): 3259–3267. Bibcode:2012GCBio..18.3259B. doi:10.1111/j.1365-2486.2012.02762.x. PMID 28741830. S2CID 31666406.
  129. ^ European Union. "Nitrates Directive".
  130. ^ Defra. . Archived from the original on 30 June 2011.
  131. ^ "Polluted Runoff: Nonpoint Source Pollution". EPA. Retrieved 23 July 2014.
  132. ^ "Washington State Dept. of Agriculture Fertilizer Product Database". Agr.wa.gov. 23 May 2012. Retrieved 17 June 2012.
  133. ^ "Metals Content for Fertilizer and Soil Amendment Products". regulatory-info-sc.com. Retrieved 21 July 2022.
  134. ^ Ju, Xiaotang; B.Gu, Y. Wu, J.N.Galloway. (2016). "Reducing China's fertilizer use by increasing farm size". Global Environmental Change. 41: 26–32. doi:10.1016/j.gloenvcha.2016.08.005.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  135. ^ Andrew, Hannah (5 July 2022). "Addressing Consolidation in Agriculture: USDA's Response to President Biden's Directive to Promote Competition in the American Economy" (PDF). Center for Agriculture and Food Systems, Vermont Law and Graduate School. p. 7. (PDF) from the original on 20 July 2022. Retrieved 7 November 2022.
  136. ^ Gomiero, T.; D. Pimental & M.G Paoletti (2011). "Environmental Impact of Different Agricultural Management Practices: Conventional vs. Organic Agriculture". Critical Reviews in Plant Sciences. 30 (1–2): 95–124. doi:10.1080/07352689.2011.554355. S2CID 83736589 – via Taylor & Francis Online.

External links

 
Wikimedia Commons has media related to Fertilizers.
 
Wikisource has the text of the 1920 Encyclopedia Americana article Fertilizers.
  • Nitrogen for Feeding Our Food, Its Earthly Origin, Haber Process
  • International Fertilizer Industry Association (IFA)
  • Nitrogen-Phosphorus-Potassium Values of Organic Fertilizers 26 February 2021 at the Wayback Machine

January 06, 2023
fertilizer, plant, food, redirects, here, drug, term, bath, salts, drug, fertilizer, american, english, fertiliser, british, english, spelling, differences, material, natural, synthetic, origin, that, applied, soil, plant, tissues, supply, plant, nutrients, di. Plant food redirects here For the drug term see Bath salts drug A fertilizer American English or fertiliser British English see spelling differences is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients Fertilizers may be distinct from liming materials or other non nutrient soil amendments Many sources of fertilizer exist both natural and industrially produced 1 For most modern agricultural practices fertilization focuses on three main macro nutrients nitrogen N phosphorus P and potassium K with occasional addition of supplements like rock flour for micronutrients Farmers apply these fertilizers in a variety of ways through dry or pelletized or liquid application processes using large agricultural equipment or hand tool methods A farmer spreading manure to improve soil fertility Historically fertilization came from natural or organic sources compost animal manure human manure harvested minerals crop rotations and byproducts of human nature industries i e fish processing waste or bloodmeal from animal slaughter However starting in the 19th century after innovations in plant nutrition an agricultural industry developed around synthetically created fertilizers This transition was important in transforming the global food system allowing for larger scale industrial agriculture with large crop yields Nitrogen fixing chemical processes such as the Haber process at the beginning of the 20th century amplified by production capacity created during World War II led to a boom in using nitrogen fertilizers 2 In the latter half of the 20th century increased the use of nitrogen fertilizers 800 increase between 1961 and 2019 have been a crucial component of the increased productivity of conventional food systems more than 30 per capita as part of the so called Green Revolution 3 The use of artificial and industrially applied fertilizers has led to a number of environmental impacts creating water pollution and Eutrophication caused by nutritional runoff carbon and other emissions from fertilizer production and mining and contamination and pollution of soil Various types of sustainable agriculture practices can be implemented to reduce the environmental impact of fertilizer uses alongside other environmental impacts of agriculture Contents 1 History 2 Mechanism 2 1 Microbiological considerations 3 Classification 3 1 Single nutrient straight fertilizers 3 2 Multinutrient fertilizers 3 3 Micronutrients 4 Environment 5 Production 5 1 Nitrogen fertilizers 5 2 Phosphate fertilizers 5 3 Potassium fertilizers 5 4 NPK fertilizers 5 5 Organic fertilizers 6 Application 6 1 Liquid vs solid 6 1 1 Urea 6 2 Slow and controlled release fertilizers 6 3 Foliar application 6 4 Chemicals that affect nitrogen uptake 6 5 Overfertilization 7 Statistics 8 Environmental effects 8 1 Water 8 1 1 Nitrate pollution 8 2 Soil 8 2 1 Acidification 8 2 2 Accumulation of toxic elements 8 2 2 1 Cadmium 8 2 2 2 Fluoride 8 2 2 3 Radioactive elements 8 2 2 4 Other metals 8 2 3 Trace mineral depletion 8 2 4 Changes in soil biology 8 3 Energy consumption and sustainability 8 3 1 Contribution to climate change 8 4 Atmosphere 9 Policy 9 1 Regulation 10 See also 11 References 12 External linksHistory EditMain article History of fertilizer Total fertilizer production by type 4 World population supported with and without synthetic nitrogen fertilizers 5 Founded in 1812 Mirat producer of manures and fertilizers is claimed to be the oldest industrial business in Salamanca Spain Management of soil fertility has preoccupied farmers for thousands of years Egyptians Romans Babylonians and early Germans are all recorded as using minerals or manure to enhance the productivity of their farms 1 The science of plant nutrition started well before the work of German chemist Justus von Liebig although his name is most mentioned Nicolas Theodore de Saussure and scientific colleagues at the time were quick to disprove the simplifications of Justus von Liebig There was a complex scientific understanding of plant nutrition where the role of humus and organo mineral interactions were central and which was in line with more recent discoveries from 1990 onwards 6 Prominent scientists on whom Justus von Liebig drew were Carl Ludwig Sprenger and Hermann Hellriegel In this field a knowledge erosion 7 took place partly driven by an intermingling of economics and research 8 John Bennet Lawes an English entrepreneur began to experiment on the effects of various manures on plants growing in pots in 1837 and a year or two later the experiments were extended to crops in the field One immediate consequence was that in 1842 he patented a manure formed by treating phosphates with sulfuric acid and thus was the first to create the artificial manure industry In the succeeding year he enlisted the services of Joseph Henry Gilbert together they performed crop experiments at the Institute of Arable Crops Research 9 The Birkeland Eyde process was one of the competing industrial processes in the beginning of nitrogen based fertilizer production 10 This process was used to fix atmospheric nitrogen N2 into nitric acid HNO3 one of several chemical processes generally referred to as nitrogen fixation The resultant nitric acid was then used as a source of nitrate NO3 A factory based on the process was built in Rjukan and Notodden in Norway combined with the building of large hydroelectric power facilities 11 The 1910s and 1920s witnessed the rise of the Haber process and the Ostwald process The Haber process produces ammonia NH3 from methane CH4 natural gas gas and molecular nitrogen N2 from the air The ammonia from the Haber process is then partially converted into nitric acid HNO3 in the Ostwald process 12 After World War II Nitrogen production plants that had ramped up for war time bomb manufacturing were pivoted towards agriculture uses 13 The use of synthetic nitrogen fertilizers has increased steadily in the last 50 years rising almost 20 fold to the current rate of 100 million tonnes of nitrogen per year 14 The development of synthetic nitrogen fertilizer has significantly supported global population growth it has been estimated that almost half the people on the Earth are currently fed as a result of synthetic nitrogen fertilizer use 15 The use of phosphate fertilizers has also increased from 9 million tonnes per year in 1960 to 40 million tonnes per year in 2000 A maize crop yielding 6 9 tonnes of grain per hectare 2 5 acres requires 31 50 kilograms 68 110 lb of phosphate fertilizer to be applied soybean crops require about half as 20 25 kg per hectare 16 Yara International is the world s largest producer of nitrogen based fertilizers 17 Mechanism Edit Six tomato plants grown with and without nitrate fertilizer on nutrient poor sand clay soil One of the plants in the nutrient poor soil has died Inorganic fertilizer use by region 18 Fertilizers enhance the growth of plants This goal is met in two ways the traditional one being additives that provide nutrients The second mode by which some fertilizers act is to enhance the effectiveness of the soil by modifying its water retention and aeration This article like many on fertilizers emphasises the nutritional aspect Fertilizers typically provide in varying proportions 19 three main macronutrients Nitrogen N leaf growth Phosphorus P development of roots flowers seeds fruit Potassium K strong stem growth movement of water in plants promotion of flowering and fruiting three secondary macronutrients calcium Ca magnesium Mg and sulfur S micronutrients copper Cu iron Fe manganese Mn molybdenum Mo zinc Zn boron B Of occasional significance are silicon Si cobalt Co and vanadium V The nutrients required for healthy plant life are classified according to the elements but the elements are not used as fertilizers Instead compounds containing these elements are the basis of fertilizers The macro nutrients are consumed in larger quantities and are present in plant tissue in quantities from 0 15 to 6 0 on a dry matter DM 0 moisture basis Plants are made up of four main elements hydrogen oxygen carbon and nitrogen Carbon hydrogen and oxygen are widely available as water and carbon dioxide Although nitrogen makes up most of the atmosphere it is in a form that is unavailable to plants Nitrogen is the most important fertilizer since nitrogen is present in proteins DNA and other components e g chlorophyll To be nutritious to plants nitrogen must be made available in a fixed form Only some bacteria and their host plants notably legumes can fix atmospheric nitrogen N2 by converting it to ammonia Phosphate is required for the production of DNA and ATP the main energy carrier in cells as well as certain lipids Microbiological considerations Edit Two sets of enzymatic reactions are highly relevant to the efficiency of nitrogen based fertilizers UreaseThe first is the hydrolysis reaction with water of urea Many soil bacteria possess the enzyme urease which catalyzes conversion of urea to ammonium ion NH4 and bicarbonate ion HCO3 Ammonia oxidationAmmonia oxidizing bacteria AOB such as species of Nitrosomonas oxidize ammonia to nitrite a process termed nitrification 20 Nitrite oxidizing bacteria especially Nitrobacter oxidize nitrite to nitrate which is extremely mobile and is a major cause of eutrophication Classification EditFertilizers are classified in several ways They are classified according to whether they provide a single nutrient e g K P or N in which case they are classified as straight fertilizers multinutrient fertilizers or complex fertilizers provide two or more nutrients for example N and P Fertilizers are also sometimes classified as inorganic the topic of most of this article versus organic Inorganic fertilizers exclude carbon containing materials except ureas Organic fertilizers are usually recycled plant or animal derived matter Inorganic are sometimes called synthetic fertilizers since various chemical treatments are required for their manufacture 21 Single nutrient straight fertilizers Edit The main nitrogen based straight fertilizer is ammonia or its solutions Ammonium nitrate NH4NO3 is also widely used Urea is another popular source of nitrogen having the advantage that it is solid and non explosive unlike ammonia and ammonium nitrate respectively A few percent of the nitrogen fertilizer market 4 in 2007 22 has been met by calcium ammonium nitrate Ca NO3 2 NH4 10 H2O The main straight phosphate fertilizers are the superphosphates Single superphosphate SSP consists of 14 18 P2O5 again in the form of Ca H2PO4 2 but also phosphogypsum CaSO4 2 H2O Triple superphosphate TSP typically consists of 44 48 of P2O5 and no gypsum A mixture of single superphosphate and triple superphosphate is called double superphosphate More than 90 of a typical superphosphate fertilizer is water soluble The main potassium based straight fertilizer is muriate of potash MOP Muriate of potash consists of 95 99 KCl and is typically available as 0 0 60 or 0 0 62 fertilizer Multinutrient fertilizers Edit These fertilizers are common They consist of two or more nutrient components Binary NP NK PK fertilizersMajor two component fertilizers provide both nitrogen and phosphorus to the plants These are called NP fertilizers The main NP fertilizers are monoammonium phosphate MAP and diammonium phosphate DAP The active ingredient in MAP is NH4H2PO4 The active ingredient in DAP is NH4 2HPO4 About 85 of MAP and DAP fertilizers are soluble in water NPK fertilizersMain article Labeling of fertilizer NPK fertilizers are three component fertilizers providing nitrogen phosphorus and potassium There exist two types of NPK fertilizers compound and blends Compound NPK fertilizers contain chemically bound ingredients while blended NPK fertilizers are physical mixtures of single nutrient components NPK rating is a rating system describing the amount of nitrogen phosphorus and potassium in a fertilizer NPK ratings consist of three numbers separated by dashes e g 10 10 10 or 16 4 8 describing the chemical content of fertilizers 23 24 The first number represents the percentage of nitrogen in the product the second number P2O5 the third K2O Fertilizers do not actually contain P2O5 or K2O but the system is a conventional shorthand for the amount of the phosphorus P or potassium K in a fertilizer A 50 pound 23 kg bag of fertilizer labeled 16 4 8 contains 8 lb 3 6 kg of nitrogen 16 of the 50 pounds an amount of phosphorus equivalent to that in 2 pounds of P2O5 4 of 50 pounds and 4 pounds of K2O 8 of 50 pounds Most fertilizers are labeled according to this N P K convention although Australian convention following an N P K S system adds a fourth number for sulfur and uses elemental values for all values including P and K 25 Micronutrients Edit Micronutrients are consumed in smaller quantities and are present in plant tissue on the order of parts per million ppm ranging from 0 15 to 400 ppm or less than 0 04 dry matter 26 27 These elements are often required for enzymes essential to the plant s metabolism Because these elements enable catalysts enzymes their impact far exceeds their weight percentage Typical micronutrients are boron zinc molybdenum iron and manganese 19 These elements are provided as water soluble salts Iron presents special problems because it converts to insoluble bio unavailable compounds at moderate soil pH and phosphate concentrations For this reason iron is often administered as a chelate complex e g the EDTA or EDDHA derivatives The micronutrient needs depend on the plant and the environment For example sugar beets appear to require boron and legumes require cobalt 1 while environmental conditions such as heat or drought make boron less available for plants 28 Environment EditSynthetic fertilizer used in agriculture has wide reaching environmental consequences According to the Intergovernmental Panel on Climate Change IPCC Special Report on Climate Change and Land production of these fertilizers and associated land use practices are drivers of global warming 3 The use of fertilizer has also led to a number of direct environmental consequences agricultural runoff which leads to downstream effects like ocean dead zones and waterway contamination soil microbiome degradation 29 and accumulation of toxins in ecosystems Indirect environmental impacts include the environmental impacts of fracking for natural gas used in the Haber process the agricultural boom is partially responsible for the rapid growth in human population and large scale industrial agricultural practices are associated with habitat destruction pressure on biodiversity and agricultural soil loss In order to mitigate environmental and food security concerns the international community has included food systems in Sustainable Development Goal 2 which focuses on creating a climate friendly and sustainable food production system 30 Most policy and regulatory approaches to address these issues focus on pivoting agricultural practices towards sustainable or regenerative agricultural practices these use less synthetic fertilizers better soil management for example no till agriculture and more organic fertilizers Production EditThe production of synthetic or inorganic fertilizers requires prepared chemicals whereas organic fertilizers are derived from the organic processes of plants and animals in biological processes using biochemicals Nitrogen fertilizers Edit Total nitrogenous fertilizer consumption per region measured in tonnes of total nutrient per year Top users of nitrogen based fertilizer 31 Country Total N use Mt pa Amt used forfeed pasture Mt pa China 18 7 3 0India 11 9 32 U S 9 1 4 7France 2 5 1 3Germany 2 0 1 2Brazil 1 7 0 7Canada 1 6 0 9Turkey 1 5 0 3UK 1 3 0 9Mexico 1 3 0 3Spain 1 2 0 5Argentina 0 4 0 1Nitrogen fertilizers are made from ammonia NH3 produced by the Haber Bosch process 22 In this energy intensive process natural gas CH4 usually supplies the hydrogen and the nitrogen N2 is derived from the air This ammonia is used as a feedstock for all other nitrogen fertilizers such as anhydrous ammonium nitrate NH4NO3 and urea CO NH2 2 Deposits of sodium nitrate NaNO3 Chilean saltpeter are also found in the Atacama desert in Chile and was one of the original 1830 nitrogen rich fertilizers used 33 It is still mined for fertilizer 34 Nitrates are also produced from ammonia by the Ostwald process Phosphate fertilizers Edit An apatite mine in Siilinjarvi Finland Phosphate fertilizers are obtained by extraction from phosphate rock which contains two principal phosphorus containing minerals fluorapatite Ca5 PO4 3F CFA and hydroxyapatite Ca5 PO4 3OH These minerals are converted into water soluble phosphate salts by treatment with sulfuric H2SO4 or phosphoric acids H3PO4 The large production of sulfuric acid is primarily motivated by this application 35 In the nitrophosphate process or Odda process invented in 1927 phosphate rock with up to a 20 phosphorus P content is dissolved with nitric acid HNO3 to produce a mixture of phosphoric acid H3PO4 and calcium nitrate Ca NO3 2 This mixture can be combined with a potassium fertilizer to produce a compound fertilizer with the three macronutrients N P and K in easily dissolved form 36 Potassium fertilizers Edit Potash is a mixture of potassium minerals used to make potassium chemical symbol K fertilizers Potash is soluble in water so the main effort in producing this nutrient from the ore involves some purification steps e g to remove sodium chloride NaCl common salt Sometimes potash is referred to as K2O as a matter of convenience to those describing the potassium content In fact potash fertilizers are usually potassium chloride potassium sulfate potassium carbonate or potassium nitrate 37 NPK fertilizers Edit Main article NPK fertilizer There are four major routes for manufacturing NPK fertilizers named for their main ingredients nitrogen N phosphorus P and potassium K steam granulation chemical granulation compaction bulk blending The first three processes are used to produce compound NPKs During steam granulation raw materials are mixed and further granulated using steam as binding agent Chemical granulation process is based on chemical reactions between liquid raw materials such as phosphoric acid sulfuric acid ammonia and solid raw materials such as potassium chloride recycle material Compaction implements high pressure to agglomerate dry powder materials Lastly bulk blends are produced by mixing straight fertilizers Organic fertilizers Edit Main article Organic fertilizer Compost bin for small scale production of organic fertilizer A large commercial compost operation Organic fertilizers can describe those fertilizers with an organic biologic origin that is fertilizers derived from living or formerly living materials Organic fertilizers can also describe commercially available and frequently packaged products that strive to follow the expectations and restrictions adopted by organic agriculture and environmentally friendly gardening related systems of food and plant production that significantly limit or strictly avoid the use of synthetic fertilizers and pesticides The organic fertilizer products typically contain both some organic materials as well as acceptable additives such as nutritive rock powders ground sea shells crab oyster etc other prepared products such as seed meal or kelp and cultivated microorganisms and derivatives Fertilizers of an organic origin the first definition include animal wastes plant wastes from agriculture seaweed compost and treated sewage sludge biosolids Beyond manures animal sources can include products from the slaughter of animals bloodmeal bone meal feather meal hides hoofs and horns all are typical components 19 Organically derived materials available to industry such as sewage sludge may not be acceptable components of organic farming and gardening because of factors ranging from residual contaminants to public perception On the other hand marketed organic fertilizers may include and promote processed organics because the materials have consumer appeal No matter the definition nor composition most of these products contain less concentrated nutrients and the nutrients are not as easily quantified They can offer soil building advantages as well as be appealing to those who are trying to farm garden more naturally 38 In terms of volume peat is the most widely used packaged organic soil amendment It is an immature form of coal and improves the soil by aeration and absorbing water but confers no nutritional value to the plants It is therefore not a fertilizer as defined in the beginning of the article but rather an amendment Coir derived from coconut husks bark and sawdust when added to soil all act similarly but not identically to peat and are also considered organic soil amendments or texturizers because of their limited nutritive inputs Some organic additives can have a reverse effect on nutrients fresh sawdust can consume soil nutrients as it breaks down and may lower soil pH but these same organic texturizers as well as compost etc may increase the availability of nutrients through improved cation exchange or through increased growth of microorganisms that in turn increase availability of certain plant nutrients Organic fertilizers such as composts and manures may be distributed locally without going into industry production making actual consumption more difficult to quantify Application Edit Applying superphosphate fertilizer by hand New Zealand 1938 Fertilizers are commonly used for growing all crops with application rates depending on the soil fertility usually as measured by a soil test and according to the particular crop Legumes for example fix nitrogen from the atmosphere and generally do not require nitrogen fertilizer Liquid vs solid Edit Fertilizers are applied to crops both as solids and as liquid About 90 of fertilizers are applied as solids The most widely used solid inorganic fertilizers are urea diammonium phosphate and potassium chloride 39 Solid fertilizer is typically granulated or powdered Often solids are available as prills a solid globule Liquid fertilizers comprise anhydrous ammonia aqueous solutions of ammonia aqueous solutions of ammonium nitrate or urea These concentrated products may be diluted with water to form a concentrated liquid fertilizer e g UAN Advantages of liquid fertilizer are its more rapid effect and easier coverage 19 The addition of fertilizer to irrigation water is called fertigation 37 Urea Edit Main article urea Urea is highly soluble in water and is therefore also very suitable for use in fertilizer solutions in combination with ammonium nitrate UAN e g in foliar feed fertilizers For fertilizer use granules are preferred over prills because of their narrower particle size distribution which is an advantage for mechanical application Urea is usually spread at rates of between 40 and 300 kg ha 35 to 270 lbs acre but rates vary Smaller applications incur lower losses due to leaching During summer urea is often spread just before or during rain to minimize losses from volatilization a process wherein nitrogen is lost to the atmosphere as ammonia gas Because of the high nitrogen concentration in urea it is very important to achieve an even spread Drilling must not occur on contact with or close to seed due to the risk of germination damage Urea dissolves in water for application as a spray or through irrigation systems In grain and cotton crops urea is often applied at the time of the last cultivation before planting In high rainfall areas and on sandy soils where nitrogen can be lost through leaching and where good in season rainfall is expected urea can be side or top dressed during the growing season Top dressing is also popular on pasture and forage crops In cultivating sugarcane urea is side dressed after planting and applied to each ratoon crop Because it absorbs moisture from the atmosphere urea is often stored in closed containers Overdose or placing urea near seed is harmful 40 Slow and controlled release fertilizers Edit This section is an excerpt from Controlled release fertiliser edit Methylene diurea MDU is component of the most popular controlled release fertilizers 41 A controlled release fertiliser CRF is a granulated fertiliser that releases nutrients gradually into the soil i e with a controlled release period 42 Controlled release fertilizer is also known as controlled availability fertilizer delayed release fertilizer metered release fertilizer or slow acting fertilizer Usually CRF refers to nitrogen based fertilizers Slow and controlled release involve only 0 15 562 000 tons of the fertilizer market 1995 Foliar application Edit Foliar fertilizers are applied directly to leaves This method is almost invariably used to apply water soluble straight nitrogen fertilizers and used especially for high value crops such as fruits Urea is the most common foliar fertilizer 19 Fertilizer burn Chemicals that affect nitrogen uptake Edit N Butylthiophosphoryltriamide an enhanced efficiency fertilizer Various chemicals are used to enhance the efficiency of nitrogen based fertilizers In this way farmers can limit the polluting effects of nitrogen run off Nitrification inhibitors also known as nitrogen stabilizers suppress the conversion of ammonia into nitrate an anion that is more prone to leaching 1 Carbamoyl 3 methylpyrazole CMP dicyandiamide nitrapyrin 2 chloro 6 trichloromethylpyridine and 3 4 Dimethylpyrazole phosphate DMPP are popular 43 Urease inhibitors are used to slow the hydrolytic conversion of urea into ammonia which is prone to evaporation as well as nitrification The conversion of urea to ammonia catalyzed by enzymes called ureases A popular inhibitor of ureases is N n butyl thiophosphoric triamide NBPT Overfertilization Edit Careful use of fertilization technologies is important because excess nutrients can be detrimental 44 Fertilizer burn can occur when too much fertilizer is applied resulting in damage or even death of the plant Fertilizers vary in their tendency to burn roughly in accordance with their salt index 45 46 Statistics Edit Fertilizer use 2018 From FAO s World Food and Agriculture Statistical Yearbook 2020 47 Recently nitrogen fertilizers have plateaued in most developed countries China although has become the largest producer and consumer of nitrogen fertilizers 48 Africa has little reliance on nitrogen fertilizers 49 Agricultural and chemical minerals are very important in industrial use of fertilizers which is valued at approximately 200 billion 50 Nitrogen has a significant impact in the global mineral use followed by potash and phosphate The production of nitrogen has drastically increased since the 1960s Phosphate and potash have increased in price since the 1960s which is larger than the consumer price index 50 Potash is produced in Canada Russia and Belarus together making up over half of the world production 50 Potash production in Canada rose in 2017 and 2018 by 18 6 51 Conservative estimates report 30 to 50 of crop yields are attributed to natural or synthetic commercial fertilizers 37 52 Fertilizer consumption has surpassed the amount of farmland in the United States 50 Global market value is likely to rise to more than US 185 billion until 2019 53 The European fertilizer market will grow to earn revenues of approx 15 3 billion in 2018 54 Data on the fertilizer consumption per hectare arable land in 2012 are published by The World Bank 55 The diagram below shows fertilizer consumption by the European Union EU countries as kilograms per hectare pounds per acre The total consumption of fertilizer in the EU is 15 9 million tons for 105 million hectare arable land area 56 or 107 million hectare arable land according to another estimate 57 This figure equates to 151 kg of fertilizers consumed per ha arable land on average by the EU countries Environmental effects Edit Runoff of soil and fertilizer during a rain stormUse of fertilizers are beneficial in providing nutrients to plants although they have some negative environmental effects The large growing consumption of fertilizers can affect soil surface water and groundwater due to dispersion of mineral use 50 See also Environmental impact of agriculture Human impact on the nitrogen cycle Nitrogen fertilizer Problems with inorganic fertilizer and Nitrogen Cycle Large pile of phosphogypsum waste near Fort Meade Florida For each ton of phosphoric acid produced by the processing of phosphate rock five tons of waste are generated This waste takes the form of impure useless radioactive solid called phosphogypsum Estimates range from 100 000 000 and 280 000 000 tons of phosphogypsum waste are produced annually worldwide 58 Water Edit Main article Eutrophication Red circles show the location and size of many dead zones Phosphorus and nitrogen fertilizers when commonly used have major environmental effects This is due to high rainfalls causing the fertilizers to be washed into waterways 59 60 Agricultural run off is a major contributor to the eutrophication of fresh water bodies For example in the US about half of all the lakes are eutrophic The main contributor to eutrophication is phosphate which is normally a limiting nutrient high concentrations promote the growth of cyanobacteria and algae the demise of which consumes oxygen 61 Cyanobacteria blooms algal blooms can also produce harmful toxins that can accumulate in the food chain and can be harmful to humans 62 63 Fertilizer run off can be reduced by using weather optimised fertilization strategies 60 The nitrogen rich compounds found in fertilizer runoff are the primary cause of serious oxygen depletion in many parts of oceans especially in coastal zones lakes and rivers The resulting lack of dissolved oxygen greatly reduces the ability of these areas to sustain oceanic fauna 64 The number of oceanic dead zones near inhabited coastlines is increasing 65 As of 2006 the application of nitrogen fertilizer is being increasingly controlled in northwestern Europe 66 and the United States 67 68 In cases where eutrophication can be reversed it may nevertheless take decades 69 and significant soil management 70 before the accumulated nitrates in groundwater can be broken down by natural processes Nitrate pollution Edit Only a fraction of the nitrogen based fertilizers is converted to plant matter The remainder accumulates in the soil or is lost as run off 71 High application rates of nitrogen containing fertilizers combined with the high water solubility of nitrate leads to increased runoff into surface water as well as leaching into groundwater thereby causing groundwater pollution 72 73 74 The excessive use of nitrogen containing fertilizers be they synthetic or natural is particularly damaging as much of the nitrogen that is not taken up by plants is transformed into nitrate which is easily leached 75 Nitrate levels above 10 mg L 10 ppm in groundwater can cause blue baby syndrome acquired methemoglobinemia 76 The nutrients especially nitrates in fertilizers can cause problems for natural habitats and for human health if they are washed off soil into watercourses or leached through soil into groundwater 77 Soil Edit Acidification Edit See also Soil pH and Soil acidification Nitrogen containing fertilizers can cause soil acidification when added 78 79 This may lead to decrease in nutrient availability which may be offset by liming Accumulation of toxic elements Edit Cadmium Edit The concentration of cadmium in phosphorus containing fertilizers varies considerably and can be problematic 80 For example mono ammonium phosphate fertilizer may have a cadmium content of as low as 0 14 mg kg or as high as 50 9 mg kg 81 The phosphate rock used in their manufacture can contain as much as 188 mg kg cadmium 82 examples are deposits on Nauru 83 and the Christmas islands 84 Continuous use of high cadmium fertilizer can contaminate soil as shown in New Zealand 85 and plants 86 Limits to the cadmium content of phosphate fertilizers has been considered by the European Commission 87 88 89 Producers of phosphorus containing fertilizers now select phosphate rock based on the cadmium content 61 Fluoride Edit Phosphate rocks contain high levels of fluoride Consequently the widespread use of phosphate fertilizers has increased soil fluoride concentrations 86 It has been found that food contamination from fertilizer is of little concern as plants accumulate little fluoride from the soil of greater concern is the possibility of fluoride toxicity to livestock that ingest contaminated soils 90 91 Also of possible concern are the effects of fluoride on soil microorganisms 90 91 92 Radioactive elements Edit The radioactive content of the fertilizers varies considerably and depends both on their concentrations in the parent mineral and on the fertilizer production process 86 93 Uranium 238 concentrations can range from 7 to 100 pCi g picocuries per gram in phosphate rock 94 and from 1 to 67 pCi g in phosphate fertilizers 95 96 97 Where high annual rates of phosphorus fertilizer are used this can result in uranium 238 concentrations in soils and drainage waters that are several times greater than are normally present 96 98 However the impact of these increases on the risk to human health from radinuclide contamination of foods is very small less than 0 05 mSv y 96 99 100 Other metals Edit Steel industry wastes recycled into fertilizers for their high levels of zinc essential to plant growth wastes can include the following toxic metals lead 101 arsenic cadmium 101 chromium and nickel The most common toxic elements in this type of fertilizer are mercury lead and arsenic 102 103 104 These potentially harmful impurities can be removed however this significantly increases cost Highly pure fertilizers are widely available and perhaps best known as the highly water soluble fertilizers containing blue dyes used around households such as Miracle Gro These highly water soluble fertilizers are used in the plant nursery business and are available in larger packages at significantly less cost than retail quantities Some inexpensive retail granular garden fertilizers are made with high purity ingredients Trace mineral depletion Edit Attention has been addressed to the decreasing concentrations of elements such as iron zinc copper and magnesium in many foods over the last 50 60 years 105 106 Intensive farming practices including the use of synthetic fertilizers are frequently suggested as reasons for these declines and organic farming is often suggested as a solution 106 Although improved crop yields resulting from NPK fertilizers are known to dilute the concentrations of other nutrients in plants 105 107 much of the measured decline can be attributed to the use of progressively higher yielding crop varieties that produce foods with lower mineral concentrations than their less productive ancestors 105 108 109 It is therefore unlikely that organic farming or reduced use of fertilizers will solve the problem foods with high nutrient density are posited to be achieved using older lower yielding varieties or the development of new high yield nutrient dense varieties 105 110 Fertilizers are in fact more likely to solve trace mineral deficiency problems than cause them In Western Australia deficiencies of zinc copper manganese iron and molybdenum were identified as limiting the growth of broad acre crops and pastures in the 1940s and 1950s 111 Soils in Western Australia are very old highly weathered and deficient in many of the major nutrients and trace elements 111 Since this time these trace elements are routinely added to fertilizers used in agriculture in this state 111 Many other soils around the world are deficient in zinc leading to deficiency in both plants and humans and zinc fertilizers are widely used to solve this problem 112 Changes in soil biology Edit Further information soil biology High levels of fertilizer may cause the breakdown of the symbiotic relationships between plant roots and mycorrhizal fungi 113 Energy consumption and sustainability Edit In the US in 2004 317 billion cubic feet of natural gas were consumed in the industrial production of ammonia less than 1 5 of total U S annual consumption of natural gas 114 A 2002 report suggested that the production of ammonia consumes about 5 of global natural gas consumption which is somewhat under 2 of world energy production 115 Ammonia is produced from natural gas and air 116 The cost of natural gas makes up about 90 of the cost of producing ammonia 117 The increase in price of natural gases over the past decade along with other factors such as increasing demand have contributed to an increase in fertilizer price 118 Contribution to climate change Edit See also Greenhouse gas emissions from agriculture The greenhouse gases carbon dioxide methane and nitrous oxide are produced during the manufacture of nitrogen fertilizer CO2 is estimated as over 1 of global CO2 emissions 119 Nitrogen fertilizer can be converted by soil bacteria to nitrous oxide a greenhouse gas 120 Nitrous oxide emissions by humans most of which are from fertilizer between 2007 and 2016 have been estimated at 7 million tonnes per year 121 which is incompatible with limiting global warming to below 2 C 122 Atmosphere Edit Global methane concentrations surface and atmospheric for 2005 note distinct plumes Through the increasing use of nitrogen fertilizer which was used at a rate of about 110 million tons of N per year in 2012 123 124 adding to the already existing amount of reactive nitrogen nitrous oxide N2O has become the third most important greenhouse gas after carbon dioxide and methane It has a global warming potential 296 times larger than an equal mass of carbon dioxide and it also contributes to stratospheric ozone depletion 125 By changing processes and procedures it is possible to mitigate some but not all of these effects on anthropogenic climate change 126 Methane emissions from crop fields notably rice paddy fields are increased by the application of ammonium based fertilizers These emissions contribute to global climate change as methane is a potent greenhouse gas 127 128 Policy EditRegulation Edit In Europe problems with high nitrate concentrations in runoff are being addressed by the European Union s Nitrates Directive 129 Within Britain farmers are encouraged to manage their land more sustainably in catchment sensitive farming 130 In the US high concentrations of nitrate and phosphorus in runoff and drainage water are classified as nonpoint source pollutants due to their diffuse origin this pollution is regulated at the state level 131 Oregon and Washington both in the United States have fertilizer registration programs with on line databases listing chemical analyses of fertilizers 132 133 In China regulations have been implemented to control the use of N fertilizers in farming In 2008 Chinese governments began to partially withdraw fertilizer subsidies including subsidies to fertilizer transportation and to electricity and natural gas use in the industry In consequence the price of fertilizer has gone up and large scale farms have begun to use less fertilizer If large scale farms keep reducing their use of fertilizer subsidies they have no choice but to optimize the fertilizer they have which would therefore gain an increase in both grain yield and profit 134 In March 2022 the United States Department of Agriculture announced a new 250M grant to promote American fertilizer production Part of the Commodity Credit Corporation the grant program will support fertilizer production that is independent of dominant fertilizer suppliers made in America and utilizing innovative production techniques to jumpstart future competition 135 Two types of agricultural management practices include organic agriculture and conventional agriculture The former encourages soil fertility using local resources to maximize efficiency Organic agriculture avoids synthetic agrochemicals Conventional agriculture uses all the components that organic agriculture does not use 136 See also EditAgroecology Circulus theory Fertigation Food and Agriculture Organization History of organic farming Milorganite Leaf Color Chart Nutrient Recovery and Reuse Phosphogypsum Soil defertilisation Seaweed fertilizerReferences Edit a b c Scherer Heinrich W Mengel Konrad Kluge Gunter Severin Karl 2009 Fertilizers 1 General Ullmann s Encyclopedia of Industrial Chemistry Weinheim Wiley VCH doi 10 1002 14356007 a10 323 pub3 Fritz Haber Science History Institute 1 June 2016 Retrieved 16 December 2022 a b Mbow et al 2019 sfn error no target CITEREFMbowRosenzweigBarioniBenton2019 help Total fertilizer production by nutrient Our World in Data Retrieved 7 March 2020 World population with and without synthetic nitrogen fertilizers Our World in Data Retrieved 5 March 2020 Visser Jozef 20 November 2019 Larramendy Marcelo Soloneski Sonia eds Opening History Gaining Perspectives Organic Fertilizers History Production and Applications IntechOpen doi 10 5772 intechopen 86185 ISBN 978 1 78985 147 2 retrieved 13 April 2021 Uekotter Frank 2010 Die Wahrheit ist auf dem Feld Eine Wissensgeschichte der deutschen Landwirtschaft Vandenhoeck amp Ruprecht ISBN 978 3 5253 1705 1 Uekotter Frank 2014 Why Panaceas Work Recasting Science Knowledge and Fertilizer Interests in German Agriculture Agricultural History 88 1 68 86 doi 10 3098 ah 2014 88 1 68 ISSN 0002 1482 JSTOR 10 3098 ah 2014 88 1 68 This article incorporates text from a publication now in the public domain Chisholm Hugh ed 1911 Lawes Sir John Bennet Encyclopaedia Britannica 11th ed Cambridge University Press Aaron John Ihde 1984 The development of modern chemistry Courier Dover Publications p 678 ISBN 978 0 486 64235 2 G J Leigh 2004 The world s greatest fix a history of nitrogen and agriculture Oxford University Press US pp 134 139 ISBN 978 0 19 516582 1 Trevor Illtyd Williams Thomas Kingston Derry 1982 A short history of twentieth century technology c 1900 c 1950 Oxford University Press pp 134 135 ISBN 978 0 19 858159 8 Philpott Tom A Brief History of Our Deadly Addiction to Nitrogen Fertilizer Mother Jones Retrieved 24 March 2021 Glass Anthony September 2003 Nitrogen Use Efficiency of Crop Plants Physiological Constraints upon Nitrogen Absorption Critical Reviews in Plant Sciences 22 5 453 470 doi 10 1080 713989757 Erisman Jan Willem MA Sutton J Galloway Z Klimont W Winiwarter October 2008 How a century of ammonia synthesis changed the world Nature Geoscience 1 10 636 639 Bibcode 2008NatGe 1 636E doi 10 1038 ngeo325 S2CID 94880859 Archived from the original on 23 July 2010 Retrieved 22 October 2010 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Vance Carroll P Uhde Stone amp Allan 2003 Phosphorus acquisition and use critical adaptations by plants for securing a non renewable resource New Phytologist 157 3 423 447 doi 10 1046 j 1469 8137 2003 00695 x JSTOR 1514050 PMID 33873400 S2CID 53490640 Mergers in the fertiliser industry The Economist 18 February 2010 Retrieved 21 February 2010 World Food and Agriculture Statistical Yearbook 2021 www fao org 2021 doi 10 4060 cb4477en ISBN 978 92 5 134332 6 S2CID 240163091 Retrieved 10 December 2021 a href Template Cite book html title Template Cite book cite book a CS1 maint url status link a b c d e Dittmar Heinrich Drach Manfred Vosskamp Ralf Trenkel Martin E Gutser Reinhold Steffens Gunter 2009 Fertilizers 2 Types Ullmann s Encyclopedia of Industrial Chemistry Weinheim Wiley VCH doi 10 1002 14356007 n10 n01 Marsh KL Sims GK Mulvaney RL 2005 Availability of urea to autotrophic ammonia oxidizing bacteria as related to the fate of 14C and 15N labeled urea added to soil Biology and Fertility of Soils 42 2 137 145 doi 10 1007 s00374 005 0004 2 S2CID 6245255 J Benton Jones Jr Inorganic Chemical Fertilisers and Their Properties in Plant Nutrition and Soil Fertility Manual Second Edition CRC Press 2012 ISBN 978 1 4398 1609 7 eBook ISBN 978 1 4398 1610 3 a b Smil Vaclav 2004 Enriching the Earth Massachusetts Institute of Technology p 135 ISBN 978 0 262 69313 4 Summary of State Fertilizer Laws PDF EPA Archived PDF from the original on 9 October 2022 Retrieved 14 March 2013 Label Requirements of specialty and other bagged fertilizers Michigan Department of Agriculture and Rural Development Retrieved 14 March 2013 National Code of Practice for Fertilizer Description amp Labelling PDF Australian Government Department of Agriculture Fisheries and Forestry Archived from the original PDF on 28 February 2015 Retrieved 14 March 2013 AESL Plant Analysis Handbook Nutrient Content of Plant Aesl ces uga edu Retrieved 11 September 2015 H A Mills J B Jones Jr 1996 Plant Analysis Handbook II A Practical Sampling Preparation Analysis and Interpretation Guide ISBN 978 1 878148 05 6 Boron Deficiency Chen Huaihai Yang Zamin K Yip Dan Morris Reese H Lebreux Steven J Cregger Melissa A Klingeman Dawn M Hui Dafeng Hettich Robert L Wilhelm Steven W Wang Gangsheng 18 June 2019 One time nitrogen fertilization shifts switchgrass soil microbiomes within a context of larger spatial and temporal variation PLOS ONE 14 6 e0211310 Bibcode 2019PLoSO 1411310C doi 10 1371 journal pone 0211310 ISSN 1932 6203 PMC 6581249 PMID 31211785 United Nations 2017 Resolution adopted by the General Assembly on 6 July 2017 Work of the Statistical Commission pertaining to the 2030 Agenda for Sustainable Development A RES 71 313 Livestock s Long Shadow Environmental Issues and Options Table 3 3 Retrieved 29 June 2009 United Nations Food and Agriculture Organization Production amp Inputs Government of India Department of Fertilizers Ministry of Chemicals and Fertilizers Supplemental technical report for sodium nitrate crops ams usda gov Archived from the original on 14 July 2014 Retrieved 6 July 2014 Caliche Ore sqm com Archived from the original on 14 July 2014 Retrieved 6 July 2014 Greenwood Norman N Earnshaw Alan 1997 Chemistry of the Elements 2nd ed Butterworth Heinemann ISBN 978 0 08 037941 8 EFMA 2000 Best available techniques for pollution prevention and control in the European fertilizer industry Booklet No 7 of 8 Production of NPK fertilizers by the nitrophosphate route PDF fertilizerseurope com European Fertilizer Manufacturers Association Archived from the original PDF on 29 July 2014 Retrieved 28 June 2014 a b c Vasant Gowariker V N Krishnamurthy Sudha Gowariker Manik Dhanorkar Kalyani Paranjape The Fertilizer Encyclopedia 2009 John Wiley amp Sons ISBN 978 0 470 41034 9 Online ISBN 978 0 470 43177 1 doi 10 1002 9780470431771 Haynes R J R Naidu 1998 Influence of lime fertilizer and manure applications on soil organic matter content and soil physical conditions a review Nutrient Cycling in Agroecosystems 51 2 123 137 doi 10 1023 A 1009738307837 S2CID 20113235 via Springer Link About Fertilizers Home Page fertilizer org International Fertilizer Association Retrieved 19 December 2017 Mikkelsen R L 2007 Biuret in Urea Fertilizers PDF Better Crops 91 3 6 7 Archived from the original PDF on 22 December 2015 Retrieved 2 May 2015 Dittmar Heinrich Drach Manfred Vosskamp Ralf Trenkel Martin E Gutser Reinhold Steffens Gunter 2009 Fertilizers 2 Types Ullmann s Encyclopedia of Industrial Chemistry Weinheim Wiley VCH doi 10 1002 14356007 n10 n01 Gregorich Edward G Turchenek L W Carter M R Angers Denis A eds 2001 Soil and Environmental Science Dictionary CRC Press p 132 ISBN 978 0 8493 3115 2 LCCN 2001025292 Retrieved 9 December 2011 Yang Ming Fang Yunting Sun Di Shi Yuanliang 2016 Efficiency of two nitrification inhibitors dicyandiamide and 3 4 dimethypyrazole phosphate on soil nitrogen transformations and plant productivity a meta analysis Scientific Reports 6 1 22075 Bibcode 2016NatSR 622075Y doi 10 1038 srep22075 ISSN 2045 2322 PMC 4763264 PMID 26902689 Nitrogen Fertilization General Information Hubcap clemson edu Archived from the original on 29 June 2012 Retrieved 17 June 2012 Garrett Howard 2014 Organic Lawn Care Growing Grass the Natural Way University of Texas Press pp 55 56 ISBN 978 0 292 72849 3 Understanding Salt index of fertilizers PDF Archived from the original PDF on 28 May 2013 Retrieved 22 July 2012 World Food and Agriculture Statistical Yearbook 2020 Rome FAO 2020 doi 10 4060 cb1329en ISBN 978 92 5 133394 5 S2CID 242794287 Smil Vaclav 2015 Making the Modern World Materials and Dematerialization United Kingdom John Wiley amp Sons ISBN 978 1 119 94253 5 Smil Vaclav 2012 Harvesting the Biosphere What We Have Taken From Nature Massachusetts Institute of Technology ISBN 978 0 262 01856 2 a b c d e Kesler and Simon Stephen and Simon 2015 Mineral Resources Economics and the Environment Cambridge ISBN 978 1 107 07491 0 Industry Stats Fertilizer Canada Fertilizer Canada Retrieved 28 March 2018 Stewart W M Dibb D W Johnston A E Smyth T J 2005 The Contribution of Commercial Fertilizer Nutrients to Food Production Agronomy Journal 97 1 6 doi 10 2134 agronj2005 0001 Ceresana Market Study Fertilizers World May 2013 Market Study Fertilizers Europe Ceresana com Fertilizer consumption Kilograms per hectare of arable land Data Eurostat Data Explorer Archived from the original on 6 October 2014 Retrieved 19 October 2011 Arable land Tayibi Hanan Choura Mohamed Lopez Felix A Alguacil Francisco J Lopez Delgado Aurora 2009 Environmental Impact and Management of Phosphogypsum Journal of Environmental Management 90 8 2377 2386 doi 10 1016 j jenvman 2009 03 007 hdl 10261 45241 PMID 19406560 Environmental impact of nitrogen and phosphorus fertilisers in high rainfall areas agric wa gov au Retrieved 9 April 2018 a b McKay Fletcher D M Ruiz S A Dias T Chadwick D R Jones D L Roose T 20 February 2021 Precipitation optimised targeting of nitrogen fertilisers in a model maize cropping system Science of the Total Environment 756 144051 Bibcode 2021ScTEn 756n4051M doi 10 1016 j scitotenv 2020 144051 ISSN 0048 9697 PMID 33280884 S2CID 227522409 a b Wilfried Werner Fertilizers 6 Environmental Aspects Ullmann s Encyclopedia of Industrial Chemistry 2002 Wiley VCH Weinheim doi 10 1002 14356007 n10 n05 UPDATE 9 30 a m Do not drink water advisory lifted for City of Toledo Toledo Free Press Archived from the original on 5 August 2014 Retrieved 5 August 2014 Schmidt JR Shaskus M Estenik JF Oesch C Khidekel R Boyer GL 2013 Variations in the microcystin content of different fish species collected from a eutrophic lake Toxins Basel 5 5 992 1009 doi 10 3390 toxins5050992 PMC 3709275 PMID 23676698 Rapid Growth Found in Oxygen Starved Ocean Dead Zones NY Times 14 August 2008 John Heilprin Associated Press Discovery Channel News Animals U N Ocean Dead Zones Growing Dsc discovery com Archived from the original on 18 June 2010 Retrieved 25 August 2010 Van Grinsven H J M Ten Berge H F M Dalgaard T Fraters B Durand P Hart A amp Willems W J 2012 Management regulation and environmental impacts of nitrogen fertilization in northwestern Europe under the Nitrates Directive a benchmark study Biogeosciences 9 12 5143 5160 Bibcode 2012BGeo 9 5143V doi 10 5194 bg 9 5143 2012 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link A Farmer s Guide To Agriculture and Water Quality Issues 3 Environmental Requirements amp Incentive Programs For Nutrient Management cals ncsu edu Archived from the original on 23 September 2015 Retrieved 3 July 2014 State EPA Nutrient Innovations Task Group 2009 An Urgent Call to Action Report of the State EPA Nutrient Innovations Task Group PDF epa gov Archived PDF from the original on 9 October 2022 Retrieved 3 July 2014 Study shows eutrophic lakes may not recover for a millennium news wisc edu Retrieved 3 November 2022 Wilkinson Grace M 1 January 2017 Eutrophication of Freshwater and Coastal Ecosystems in Abraham Martin A ed Encyclopedia of Sustainable Technologies Oxford Elsevier pp 145 152 doi 10 1016 b978 0 12 409548 9 10160 5 ISBN 978 0 12 804792 7 retrieved 3 November 2022 Callisto Marcos Molozzi Joseline Barbosa Jose Lucena Etham 2014 Eutrophication of Lakes Eutrophication Causes Consequences and Control pp 55 71 doi 10 1007 978 94 007 7814 6 5 ISBN 978 94 007 7813 9 C J Rosen B P Horgan 9 January 2009 Preventing Pollution Problems from Lawn and Garden Fertilizers Extension umn edu Archived from the original on 10 March 2014 Retrieved 25 August 2010 Bijay Singh Yadvinder Singh Sekhon G S 1995 Fertilizer N use efficiency and nitrate pollution of groundwater in developing countries Journal of Contaminant Hydrology 20 3 4 167 184 Bibcode 1995JCHyd 20 167S doi 10 1016 0169 7722 95 00067 4 NOFA Interstate Council The Natural Farmer Ecologically Sound Nitrogen Management Mark Schonbeck Nofa org 25 February 2004 Archived from the original on 24 March 2004 Retrieved 25 August 2010 Jackson Louise E Burger Martin Cavagnaro Timothy R 2008 Roots Nitrogen Transformations and Ecosystem Services Annual Review of Plant Biology 59 341 363 doi 10 1146 annurev arplant 59 032607 092932 PMID 18444903 Knobeloch L Salna B Hogan A Postle J Anderson H 2000 Blue Babies and Nitrate Contaminated Well Water Environ Health Perspect 108 7 675 8 doi 10 1289 ehp 00108675 PMC 1638204 PMID 10903623 Nitrogen and Water Schindler D W Hecky R E 2009 Eutrophication More Nitrogen Data Needed Science 324 5928 721 722 Bibcode 2009Sci 324 721S doi 10 1126 science 324 721b PMID 19423798 Penn C J Bryant R B 2008 Phosphorus Solubility in Response to Acidification of Dairy Manure Amended Soils Soil Science Society of America Journal 72 1 238 Bibcode 2008SSASJ 72 238P doi 10 2136 sssaj2007 0071N McLaughlin M J Tiller K G Naidu R Stevens D P 1996 Review the behaviour and environmental impact of contaminants in fertilizers Soil Research 34 1 54 doi 10 1071 sr9960001 Lugon Moulin N Ryan L Donini P Rossi L 2006 Cadmium content of phosphate fertilizers used for tobacco production PDF Agron Sustain Dev 26 3 151 155 doi 10 1051 agro 2006010 S2CID 13996565 Archived PDF from the original on 9 October 2022 Retrieved 27 June 2014 Zapata F Roy R N 2004 Use of Phosphate Rocks for Sustainable Agriculture Secondary nutrients micronutrients liming effect and hazardous elements associated with phosphate rock use fao org FAO Retrieved 27 June 2014 Syers JK Mackay AD Brown MW Currie CD 1986 Chemical and physical characteristics of phosphate rock materials of varying reactivity J Sci Food Agric 37 11 1057 1064 doi 10 1002 jsfa 2740371102 Trueman NA 1965 The phosphate volcanic and carbonate rocks of Christmas Island Indian Ocean J Geol Soc Aust 12 2 261 286 Bibcode 1965AuJES 12 261T doi 10 1080 00167616508728596 Taylor MD 1997 Accumulation of Cadmium derived from fertilizers in New Zealand soils Science of the Total Environment 208 1 2 123 126 Bibcode 1997ScTEn 208 123T doi 10 1016 S0048 9697 97 00273 8 PMID 9496656 a b c Chaney R L 2012 Food safety issues for mineral and organic fertilizers Advances in Agronomy Vol 117 pp 51 99 doi 10 1016 b978 0 12 394278 4 00002 7 ISBN 9780123942784 Oosterhuis F H Brouwer F M Wijnants H J 2000 A possible EU wide charge on cadmium in phosphate fertilisers Economic and environmental implications PDF dare ubvu vu nl Archived PDF from the original on 9 October 2022 Retrieved 27 June 2014 Fertilizers Europe 2014 Putting all the cards on the table PDF fertilizerseurope com Archived from the original PDF on 8 August 2014 Retrieved 27 June 2014 Wates J 2014 Revision of the EU fertilizer regulation and cadmium content of fertilisers iatp org Retrieved 27 June 2014 a b Loganathan P Hedley M J Grace N D 2008 Pasture soils contaminated with fertilizer derived cadmium and fluorine livestock effects Reviews of Environmental Contamination and Toxicology Vol 192 pp 29 66 doi 10 1007 978 0 387 71724 1 2 ISBN 978 0 387 71723 4 PMID 18020303 a b Cronin S J Manoharan V Hedley M J Loganathan P 2000 Fluoride A review of its fate bioavailability and risks of fluorosis in grazed pasture systems in New Zealand New Zealand Journal of Agricultural Research 43 3 295 3214 doi 10 1080 00288233 2000 9513430 Wilke B M 1987 Fluoride induced changes in chemical properties and microbial activity of mull moder and mor soils Biology and Fertility of Soils 5 49 55 doi 10 1007 BF00264346 S2CID 1225884 Mortvedt JJ Beaton JD Heavy Metal and Radionuclide Contaminants in Phosphate Fertilizers Archived from the original on 26 July 2014 Retrieved 16 July 2014 TENORM Fertilizer and Fertilizer Production Wastes US EPA 2016 Retrieved 30 August 2017 Khater A E M 2008 Uranium and heavy metals in phosphate fertilizers PDF radioecology info Archived from the original PDF on 24 July 2014 Retrieved 17 July 2014 a b c NCRP 1987 Radiation Exposure of the U S Population from Consumer Products and Miscellaneous Sources National Council on Radiation Protection and Measurements pp 29 32 Retrieved 17 July 2014 permanent dead link Hussein EM 1994 Radioactivity of phosphate ore superphosphate and phosphogypsum in Abu zaabal phosphate Health Physics 67 3 280 282 doi 10 1097 00004032 199409000 00010 PMID 8056596 Barisic D Lulic S Miletic P 1992 Radium and uranium in phosphate fertilizers and their impact on the radioactivity of waters Water Research 26 5 607 611 doi 10 1016 0043 1354 92 90234 U Hanlon E A 2012 Naturally Occurring Radionuclides in Agricultural Products edis ifas ufl edu University of Florida Archived from the original on 25 July 2014 Retrieved 17 July 2014 Sharpley A N Menzel R G 1987 The impact of soil and fertilizer phosphorus on the environment Advances in Agronomy Vol 41 pp 297 324 doi 10 1016 s0065 2113 08 60807 x ISBN 9780120007417 S2CID 83005521 a b Wilson Duff 3 July 1997 Business Fear in the Fields How Hazardous Wastes Become Fertilizer Spreading Heavy Metals on Farmland Is Perfectly Legal But Little Research Has Been Done To Find Out Whether It s Safe Seattle Times Newspaper Community seattletimes nwsource com Retrieved 25 August 2010 Waste Lands The Threat of Toxic Fertilizer Pirg org 3 July 1997 Archived from the original on 26 November 2010 Retrieved 25 August 2010 mindfully org Waste Lands The Threat of Toxic Fertilizer Released by PIRG Toxic Wastes Found in Fertilizers Cat Lazaroff ENS 7may01 Mindfully org Archived from the original on 11 January 2002 Retrieved 25 August 2010 Zapata F Roy RN 2004 Use of phosphate rocks for sustainable agriculture PDF Rome FAO p 82 Retrieved 16 July 2014 permanent dead link a b c d Davis D R Epp M D Riordan H D 2004 Changes in USDA Food Composition Data for 43 Garden Crops 1950 to 1999 Journal of the American College of Nutrition 23 6 669 682 doi 10 1080 07315724 2004 10719409 PMID 15637215 S2CID 13595345 a b Thomas D 2007 The mineral depletion of foods available to us as a nation 1940 2002 A Review of the 6th Edition of McCance and Widdowson Nutrition and Health 19 1 2 21 55 doi 10 1177 026010600701900205 PMID 18309763 S2CID 372456 Jarrell W M Beverly R B 1981 The Dilution Effect in Plant Nutrition Studies Advances in Agronomy Vol 34 pp 197 224 doi 10 1016 s0065 2113 08 60887 1 ISBN 9780120007349 Fan M S Zhao F J Fairweather Tait S J Poulton P R Dunham S J McGrath S P 2008 Evidence of decreasing mineral density in wheat grain over the last 160 years Journal of Trace Elements in Medicine and Biology 22 4 315 324 doi 10 1016 j jtemb 2008 07 002 PMID 19013359 Zhao F J Su Y H Dunham S J Rakszegi M Bedo Z McGrath S P Shewry P R 2009 Variation in mineral micronutrient concentrations in grain of wheat lines of diverse origin Journal of Cereal Science 49 2 290 295 doi 10 1016 j jcs 2008 11 007 Saltzman A Birol E Bouis H E Boy E De Moura F F Islam Y Pfeiffer W H 2013 Biofortification progress toward a more nourishing future Global Food Security 2 9 17 doi 10 1016 j gfs 2012 12 003 a b c Moore Geoff 2001 Soilguide A handbook for understanding and managing agricultural soils Perth Western Australia Agriculture Western Australia pp 161 207 ISBN 978 0 7307 0057 9 Zinc in Soils and Crop Nutrition Scribd com 25 August 2010 Retrieved 17 June 2012 Carroll and Salt Steven B and Steven D 2004 Ecology for Gardeners Cambridge Timber Press ISBN 978 0 88192 611 8 Aleksander Abram D Lynn Forster 2005 A Primer on Ammonia Nitrogen Fertilizers and Natural Gas Markets Department of Agricultural Environmental and Development Economics Ohio State University 38 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help IFA Statistics Fertilizer Indicators Details Raw material reserves 2002 10 Archived 24 April 2008 at the Wayback Machine Appl Max 2000 Ammonia 2 Production Processes Ullmann s Encyclopedia of Industrial Chemistry Weinheim Germany Wiley VCH pp 139 225 doi 10 1002 14356007 o02 o11 ISBN 978 3 527 30673 2 Sawyer JE 2001 Natural gas prices affect nitrogen fertilizer costs IC 486 1 8 Table 8 Fertilizer price indexes 1960 2007 Archived from the original on 6 March 2010 Green Ammonia and the Electrification of the Haber Bosch Process Reduce Carbon Emissions guidehouseinsights com Retrieved 6 March 2022 How Fertilizer Is Making Climate Change Worse BloombergQuint Retrieved 25 March 2021 Tian Hanqin Xu Rongting Canadell Josep G Thompson Rona L Winiwarter Wilfried Suntharalingam Parvadha Davidson Eric A Ciais Philippe Jackson Robert B Janssens Maenhout Greet Prather Michael J October 2020 A comprehensive quantification of global nitrous oxide sources and sinks Nature 586 7828 248 256 Bibcode 2020Natur 586 248T doi 10 1038 s41586 020 2780 0 ISSN 1476 4687 PMID 33028999 S2CID 222217027 Archived from the original on 13 October 2020 Alt URL Nitrogen fertiliser use could threaten global climate goals Carbon Brief 7 October 2020 Retrieved 25 March 2021 FAO 2012 Current world fertilizer trends and outlook to 2016 PDF Rome Food and Agriculture Organization of the United Nations p 13 Archived from the original PDF on 18 May 2017 Retrieved 3 July 2014 Gruber N Galloway JN 2008 An Earth system perspective of the global nitrogen cycle Nature 451 7176 293 296 Bibcode 2008Natur 451 293G doi 10 1038 nature06592 PMID 18202647 Human alteration of the nitrogen cycle threats benefits and opportunities Archived 14 January 2009 at the Wayback Machine UNESCO SCOPE Policy briefs April 2007 Roy R N Misra R V Montanez A 2002 Decreasing reliance on mineral nitrogen yet more food PDF Ambio A Journal of the Human Environment 31 2 177 183 doi 10 1579 0044 7447 31 2 177 PMID 12078007 S2CID 905322 Archived from the original PDF on 24 September 2015 Retrieved 3 July 2014 Bodelier Paul L E Peter Roslev3 Thilo Henckel1 amp Peter Frenzel1 November 1999 Stimulation by ammonium based fertilizers of methane oxidation in soil around rice roots Nature 403 6768 421 424 Bibcode 2000Natur 403 421B doi 10 1038 35000193 PMID 10667792 S2CID 4351801 Banger K Tian H Lu C 2012 Do nitrogen fertilizers stimulate or inhibit methane emissions from rice fields Global Change Biology 18 10 3259 3267 Bibcode 2012GCBio 18 3259B doi 10 1111 j 1365 2486 2012 02762 x PMID 28741830 S2CID 31666406 European Union Nitrates Directive Defra Catchment Sensitive Farming Archived from the original on 30 June 2011 Polluted Runoff Nonpoint Source Pollution EPA Retrieved 23 July 2014 Washington State Dept of Agriculture Fertilizer Product Database Agr wa gov 23 May 2012 Retrieved 17 June 2012 Metals Content for Fertilizer and Soil Amendment Products regulatory info sc com Retrieved 21 July 2022 Ju Xiaotang B Gu Y Wu J N Galloway 2016 Reducing China s fertilizer use by increasing farm size Global Environmental Change 41 26 32 doi 10 1016 j gloenvcha 2016 08 005 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Andrew Hannah 5 July 2022 Addressing Consolidation in Agriculture USDA s Response to President Biden s Directive to Promote Competition in the American Economy PDF Center for Agriculture and Food Systems Vermont Law and Graduate School p 7 Archived PDF from the original on 20 July 2022 Retrieved 7 November 2022 Gomiero T D Pimental amp M G Paoletti 2011 Environmental Impact of Different Agricultural Management Practices Conventional vs Organic Agriculture Critical Reviews in Plant Sciences 30 1 2 95 124 doi 10 1080 07352689 2011 554355 S2CID 83736589 via Taylor amp Francis Online External links Edit Wikimedia Commons has media related to Fertilizers Wikisource has the text of the 1920 Encyclopedia Americana article Fertilizers Nitrogen for Feeding Our Food Its Earthly Origin Haber Process International Fertilizer Industry Association IFA Agriculture Guide Complete Guide to Fertilizers and Fertilization Nitrogen Phosphorus Potassium Values of Organic Fertilizers Archived 26 February 2021 at the Wayback Machine Retrieved from https en wikipedia org w index php title Fertilizer amp oldid 1131955572, wikipedia, wiki, book, books, library,

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