Agricultural pollution

Last updated
Water pollution due to dairy farming in the Wairarapa area of New Zealand (photographed in 2003) Water pollution in the Wairarapa.JPG
Water pollution due to dairy farming in the Wairarapa area of New Zealand (photographed in 2003)

Agricultural pollution refers to biotic and abiotic byproducts of farming practices that result in contamination or degradation of the environment and surrounding ecosystems, and/or cause injury to humans and their economic interests. The pollution may come from a variety of sources, ranging from point source water pollution (from a single discharge point) to more diffuse, landscape-level causes, also known as non-point source pollution and air pollution. Once in the environment these pollutants can have both direct effects in surrounding ecosystems, i.e. killing local wildlife or contaminating drinking water, and downstream effects such as dead zones caused by agricultural runoff is concentrated in large water bodies.

Contents

Management practices, or ignorance of them, play a crucial role in the amount and impact of these pollutants. Management techniques range from animal management and housing to the spread of pesticides and fertilizers in global agricultural practices, which can have major environmental impacts. Bad management practices include poorly managed animal feeding operations, overgrazing, plowing, fertilizer, and improper, excessive, or badly timed use of pesticides.

Pollutants from agriculture greatly affect water quality and can be found in lakes, rivers, wetlands, estuaries, and groundwater. Pollutants from farming include sediments, nutrients, pathogens, pesticides, metals, and salts. [1] Animal agriculture has an outsized impact on pollutants that enter the environment. Bacteria and pathogens in manure can make their way into streams and groundwater if grazing, storing manure in lagoons and applying manure to fields is not properly managed. [2] Air pollution caused by agriculture through land use changes and animal agriculture practices have an outsized impact on climate change. Addressing these concerns was a central part of the IPCC Special Report on Climate Change and Land [3] as well as in the 2024 UNEP Actions on Air Quality report. [4] Mitigation of agricultural pollution is a key component in the development of a sustainable food system. [5] [6] [7]

Abiotic sources

Pesticides

Aerial application of pesticide Cropduster spraying pesticides.jpg
Aerial application of pesticide

It has been approximated that in the absence of pest control measures, crop losses before harvesting would typically amount to 40 percent. [8] Persistence is a major issue. For example 2,4-D and atrazine have with lifetimes up to 20 years—such as DDT, aldrin, dieldrin, endrin, heptachlor, and toxaphene), or even permanent (as seen in substances like lead, mercury, and arsenic). [9] The extent to which the pesticides and herbicides persist depends on the compound's unique chemistry, which affects sorption dynamics and resulting fate and transport in the soil environment. [10] Pesticides can also accumulate in animals that eat contaminated pests and soil organisms. The primary danger associated with pesticide application lies in its impact on non-target organisms. [11] These encompass species we typically perceive as beneficial or desirable, such as pollinators, and to natural enemies of pests (i.e. insects that prey on or parasitize pests). [12]

In principle, biopesticides, derived from natural sources, [13] could reduce overall agricultural pollution. Their utilization is modest. Furthermore, biopesticides often suffer the same negative impacts as synthetic pesticides. [14] In the United States, biopesticides are subject to fewer environmental regulations. Many biopesticides are permitted under the National Organic Program, United States Department of Agriculture, standards for organic crop production. [13]

Pesticide leaching

Pesticide leaching occurs when pesticides dissolve in water, and these solutions migrate to off-target sites. Leaching is a major source of groundwater pollution. Leaching is affected by the soil, the pesticide, and rainfall and irrigation. Leaching is most likely to happen if using a water-soluble pesticide, when the soil tends to be sandy in texture; if excessive watering occurs just after pesticide application; if the adsorption ability of the pesticide to the soil is low. Leaching may not only originate from treated fields, but also from pesticide mixing areas, pesticide application machinery washing sites, or disposal areas. [15]

Fertilizers

Fertilizers are used to provide crops with additional sources of nutrients, such as nitrogen, phosphorus, and potassium, that promote plant growth and increase crop yields. While they are beneficial for plant growth, they can also disrupt natural nutrient and mineral biogeochemical cycles and pose risks to human and ecological health.

Nitrogen

Most common nitrogen sources are NO3− (nitrate) and NH4+ (ammonium). These fertilizers have greatly increased the productivity of agricultural land:

With average crop yields remaining at the 1900 level the crop harvest in the year 2000 would have required nearly four times more land and the cultivated area would have claimed nearly half of all ice-free continents, rather than under 15% of the total land area that is required today. [16]

— Vaclav Smil, Nitrogen cycle and world food production, Volume 2, pages 9–13

Although leading to increased crop yield, nitrogen fertilizers can also negatively affect groundwater and surface waters, pollute the atmosphere, and degrade soil health.[ citation needed ] Not all nutrient applied through fertilizer are taken up by the crops, and the remainder accumulates in the soil or is lost as runoff. Nitrate fertilizers are much more likely to be lost to the soil profile through runoff because of its high solubility and like charges between the molecule and negatively charged clay particles. [17] 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. Nitrate levels above 10 mg/L (10 ppm) in groundwater can cause "blue baby syndrome" (acquired methemoglobinemia) in infants and possibly thyroid disease and various types of cancer. [18] Nitrogen fixation, which converts atmospheric nitrogen (N2) to ammonia, and denitrification, which converts biologically available nitrogen compounds to N2 and N2O, are two of the most important metabolic processes involved in the nitrogen cycle because they are the largest inputs and outputs of nitrogen to ecosystems. They allow nitrogen to flow between the atmosphere, which is around 78% nitrogen) and the biosphere. Other significant processes in the nitrogen cycle are nitrification and ammonification which convert ammonium to nitrate or nitrite and organic matter to ammonia respectively. Because these processes keep nitrogen concentrations relatively stable in most ecosystems, a large influx of nitrogen from agricultural runoff can cause serious disruption. [19] A common result of this in aquatic ecosystems is eutrophication, which in turn creates hypoxic and anoxic conditions – both of which are deadly and/or damaging to many species. [20] Nitrogen fertilization can also release NH3 gases into the atmosphere which can then be converted into NOx compounds. A greater amount of NOx compounds in the atmosphere can result in the acidification of aquatic ecosystems and cause various respiratory issues in humans. Fertilization can also release N2O which is a greenhouse gas and can facilitate the destruction of ozone (O3) in the stratosphere. [21] Soils that receive nitrogen fertilizers can also be damaged. An increase in plant available nitrogen will increase a crop's net primary production, and eventually, soil microbial activity will increase as a result of the larger inputs of nitrogen from fertilizers and carbon compounds through decomposed biomass. Excess nitrogen can disrupt mutualisms; for example, in the legumes-rhizobia resource mutualism nitrogen deposition results in the evolution of less-cooperative rhizobia. [22] Because of the increase in decomposition in the soil, its organic matter content will be depleted which results in lower overall soil health. [23]

Phosphorus

The most common form of phosphorus fertilizer used in agricultural practices is phosphate (PO43-), and it is applied in synthetic compounds that incorporate PO43- or in organic forms such as manure and compost. [24] Phosphorus is an essential nutrient in all organisms because of the roles it plays in cell and metabolic functions such as nucleic acid production and metabolic energy transfers. However, most organisms, including agricultural crops, only require a small amount of phosphorus because they have evolved in ecosystems with relatively low amounts of it. [25] Microbial populations in soils are able to convert organic forms of phosphorus to soluble plant available forms such as phosphate. This step is generally bypassed with inorganic fertilizers because it is applied as phosphate or other plant available forms. Any phosphorus that is not taken up by plants is adsorbed to soil particles which helps it remain in place. Because of this, it typically enters surface waters when the soil particles it is attached to are eroded as a result of precipitation or stormwater runoff. The amount that enters surface waters is relatively low in comparison to the amount that is applied as fertilizer, but because it acts as a limiting nutrient in most environments, even a small amount can disrupt an ecosystem's natural phosphorus biogeochemical cycles. [26] Although nitrogen plays a role in harmful algae and cyanobacteria blooms that cause eutrophication, excess phosphorus is considered the largest contributing factor due to the fact that phosphorus is often the most limiting nutrient, especially in freshwaters. [27] In addition to depleting oxygen levels in surface waters, algae and cyanobacteria blooms can produce cyanotoxins which are harmful to human and animal health as well as many aquatic organisms. [28]

The concentration of cadmium in phosphorus-containing fertilizers varies considerably and can be problematic. 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. This is because the phosphate rock used in their manufacture can contain as much as 188 mg/kg cadmium (examples are deposits on Nauru and the Christmas islands). Continuous use of high-cadmium fertilizer can contaminate soil and plants. Limits to the cadmium content of phosphate fertilizers has been considered by the European Commission. Producers of phosphorus-containing fertilizers now select phosphate rock based on the cadmium content. [29] Phosphate rocks contain high levels of fluoride. Consequently, the widespread use of phosphate fertilizers has increased soil fluoride concentrations. 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. Also of possible concern are the effects of fluoride on soil microorganisms. [30]

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. Uranium-238 concentrations range can range from 7 to 100 pCi/g in phosphate rock and from 1 to 67 pCi/g in phosphate fertilizers. 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. However, the impact of these increases on the risk to human health from radionuclide contamination of foods is very small (less than 0.05 mSv/y).[ citation needed ]

From machinery

Farm machinery and equipment emitting substantial quantities of harmful gases. [31]

Land management

Soil erosion and sedimentation

Soil erosion: soil has washed from a ploughed field through this gate and into a watercourse beyond. Soil erosion - geograph.org.uk - 1135515.jpg
Soil erosion: soil has washed from a ploughed field through this gate and into a watercourse beyond.

Agriculture contributes greatly to soil erosion and sediment deposition through intensive management or inefficient land cover. [32] It is estimated that agricultural land degradation is leading to an irreversible decline in fertility on about 6 million ha of fertile land each year. [33] The accumulation of sediments (i.e. sedimentation) in runoff water affects water quality in various ways.[ citation needed ] Sedimentation can decrease the transport capacity of ditches, streams, rivers, and navigation channels. It can also limit the amount of light penetrating the water, which affects aquatic biota. The resulting turbidity from sedimentation can interfere with feeding habits of fishes, affecting population dynamics. Sedimentation also affects the transport and accumulation of pollutants, including phosphorus and various pesticides. [34]

Tillage and nitrous oxide emissions

Natural soil biogeochemical processes result in the emission of various greenhouse gases, including nitrous oxide. Agricultural management practices can affect emission levels. For example, tillage levels have also been shown to affect nitrous oxide emissions. [35]

Organic farming and conservation agriculture in mitigation

Organic farming

This section is an excerpt from Organic food § Environmental sustainability.[ edit ]

From an environmental perspective, fertilizing, overproduction and the use of pesticides in conventional farming has caused, and is causing, enormous damage worldwide to local ecosystems, soil health, [36] [37] [38] biodiversity, groundwater and drinking water supplies, and sometimes farmers' health and fertility. [39] [40] [41] [42] [43]

Organic farming typically reduces some environmental impact relative to conventional farming, but the scale of reduction can be difficult to quantify and varies depending on farming methods. In some cases, reducing food waste and dietary changes might provide greater benefits. [43] A 2020 study at the Technical University of Munich found that the greenhouse gas emissions of organically farmed plant-based food were lower than conventionally-farmed plant-based food. The greenhouse gas costs of organically produced meat were approximately the same as non-organically produced meat. [44] [45] However, the same paper noted that a shift from conventional to organic practices would likely be beneficial for long-term efficiency and ecosystem services, and probably improve soil over time. [45]

A 2019 life-cycle assessment study found that converting the total agricultural sector (both crop and livestock production) for England and Wales to organic farming methods would result in a net increase in greenhouse gas emissions as increased overseas land use for production and import of crops would be needed to make up for lower organic yields domestically. [46]

Conservation agriculture

Conservation agriculture relies on principles of minimal soil disturbance, the use of mulch and/or cover crops as soil cover, and crop species diversification. [47] It enables the reduction of fertilizers, which in turn reduces ammonia emissions and greenhouse gas emissions. [4] [48] It also stabilizes soil, which slows down the release of carbon into the atmosphere. [49]

Biotic sources

Organic contaminants

Manures and biosolids, although having value as fertilizers, they may also contain contaminants, including pharmaceuticals and personal care products (PPCPs). A wide variety and vast quantity of PPCPs consumed by animals. [50]

Greenhouse gases from fecal waste

The United Nations Food and Agriculture Organization (FAO) predicted that 18% of anthropogenic greenhouse gases come directly or indirectly from the world's livestock. This report also suggested that the emissions from livestock were greater than that of the transportation sector. While livestock do currently play a role in producing greenhouse gas emissions, the estimates have been argued to be a misrepresentation. While the FAO used a life-cycle assessment of animal agriculture (i.e. all aspects including emissions from growing crops for feed, transportation to slaughter, etc.), they did not apply the same assessment for the transportation sector. [51]

Alternate sources [52] claim that FAO estimates are too low, stating that the global livestock industry could be responsible for up to 51% of emitted atmospheric greenhouse gasses rather than 18%. [53] Critics say the difference in estimates come from the FAO's use of outdated data. Regardless, if the FAO's report of 18% is accurate, that still makes livestock the second-largest greenhouse-gas-polluter.

A PNAS model showed that even if animals were completely removed from U.S. agriculture and diets, U.S. GHG emissions would be decreased by 2.6% only (or 28% of agricultural GHG emissions). This is because of the need replace animal manures by fertilizers and to replace also other animal coproducts, and because livestock now use human-inedible food and fiber processing byproducts. Moreover, people would suffer from a greater number of deficiencies in essential nutrients although they would get a greater excess of energy, possibly leading to greater obesity. [54]

Introduced species

Invasive species

Centaurea solstitialis, an aggressively invasive weed, was probably introduced to North America in contaminated fodder seed. Agricultural practices such as tilling and livestock grazing aided in its rapid spread. It is toxic to horses, prevents native plants from growing (decreasing biodiversity and degrading natural ecosystems), and is a physical barrier to the migration of indigenous animals. Yellow star thistle.jpg
Centaurea solstitialis , an aggressively invasive weed, was probably introduced to North America in contaminated fodder seed. Agricultural practices such as tilling and livestock grazing aided in its rapid spread. It is toxic to horses, prevents native plants from growing (decreasing biodiversity and degrading natural ecosystems), and is a physical barrier to the migration of indigenous animals.

The increasing globalization of agriculture has resulted in the accidental transport of pests, weeds, and diseases to novel ranges. If they establish, they become an invasive species that can impact populations of native species [55] and threaten agricultural production. [12] For example, the transport of bumblebees reared in Europe and shipped to the United States and/or Canada for use as commercial pollinators has led to the introduction of an Old World parasite to the New World. [56] This introduction may play a role in recent native bumble bee declines in North America. [57] Agriculturally introduced species can also hybridize with native species resulting in a decline in genetic biodiversity [55] and threaten agricultural production. [12]

Habitat disturbance associated with farming practices themselves can also facilitate the establishment of these introduced organisms. Contaminated machinery, livestock and fodder, and contaminated crop or pasture seed can also lead to the spread of weeds. [58]

Quarantines (see biosecurity) are one way in which prevention of the spread of invasive species can be regulated at the policy level. A quarantine is a legal instrument that restricts the movement of infested material from areas where an invasive species is present to areas in which it is absent. The World Trade Organization has international regulations concerning the quarantine of pests and diseases under the Agreement on the Application of Sanitary and Phytosanitary Measures. Individual countries often have their own quarantine regulations. In the United States, for example, the United States Department of Agriculture/Animal and Plant Health Inspection Service (USDA/APHIS) administers domestic (within the United States) and foreign (importations from outside the United States) quarantines. These quarantines are enforced by inspectors at state borders and ports of entry. [13]

Biological control

The use of biological pest control agents, or using predators, parasitoids, parasites, and pathogens to control agricultural pests, has the potential to reduce agricultural pollution associated with other pest control techniques, such as pesticide use. The merits of introducing non-native biocontrol agents have been widely debated, however. Once released, the introduction of a biocontrol agent can be irreversible. Potential ecological issues could include the dispersal from agricultural habitats into natural environments, and host-switching or adapting to utilize a native species. In addition, predicting the interaction outcomes in complex ecosystems and potential ecological impacts prior to release can be difficult. One example of a biocontrol program that resulted in ecological damage occurred in North America, where a parasitoid of butterflies was introduced to control gypsy moth and browntail moth. This parasitoid is capable of utilizing many butterfly host species, and likely resulted in the decline and extirpation of several native silk moth species. [59]

International exploration for potential biocontrol agents is aided by agencies such as the European Biological Control Laboratory, the United States Department of Agriculture/Agricultural Research Service (USDA/ARS), the Commonwealth Institute of Biological Control, and the International Organization for Biological Control of Noxious Plants and Animals. In order to prevent agricultural pollution, quarantine and extensive research on the organism's potential efficacy and ecological impacts are required prior to introduction. If approved, attempts are made to colonize and disperse the biocontrol agent in appropriate agricultural settings. Continual evaluations on their efficacy are conducted. [13]

Genetically modified organisms (GMO)

(Top) Non transgenic peanut leaves showing extensive damage from European corn borer larvae. (Bottom) Peanut leaves genetically engineered to produce Bt toxins are protected from herbivory damage. Bt plants.png
(Top) Non transgenic peanut leaves showing extensive damage from European corn borer larvae. (Bottom) Peanut leaves genetically engineered to produce Bt toxins are protected from herbivory damage.

Genetic contamination and ecological effects

GMO crops can, however, result in genetic contamination of native plant species through hybridization. This could lead to increased weediness of the plant or the extinction of the native species. In addition, the transgenic plant itself may become a weed if the modification improves its fitness in a given environment. [12]

There are also concerns that non-target organisms, such as pollinators and natural enemies, could be poisoned by accidental ingestion of Bt-producing plants. A recent study testing the effects of Bt corn pollen dusting nearby milkweed plants on larval feeding of the monarch butterfly found that the threat to populations of the monarch was low. [12]

The use of GMO crop plants engineered for herbicide resistance can also indirectly increase the amount of agricultural pollution associated with herbicide use. For example, the increased use of herbicide in herbicide-resistant corn fields in the mid-western United States is decreasing the amount of milkweeds available for monarch butterfly larvae. [12]

Regulation of the release of genetic modified organisms vary based on the type of organism and the country concerned. [60]

GMO as a tool of pollution reduction

While there may be some concerns regarding the use of GM products, it may also be the solution to some of the existing animal agriculture pollution issues. One of the main sources of pollution, particularly vitamin and mineral drift in soils, comes from a lack of digestive efficiency in animals. By improving digestive efficiency, it is possible to minimize both the cost of animal production and the environmental damage. One successful example of this technology and its potential application is the Enviropig.[ citation needed ]

The Enviropig is a genetically modified Yorkshire pig that expresses phytase in its saliva. Grains, such as corn and wheat, have phosphorus that is bound in a naturally indigestible form known as phytic acid. Phosphorus, an essential nutrient for pigs, is then added to the diet, since it can not be broken down in the pigs digestive tract. As a result, nearly all of the phosphorus naturally found in the grain is wasted in the feces, and can contribute to elevated levels in the soil. Phytase is an enzyme that is able to break down the otherwise indigestible phytic acid, making it available to the pig. The ability of the Enviropig to digest the phosphorus from the grains eliminates the waste of that natural phosphorus (20-60% reduction), while also eliminating the need to supplement the nutrient in feed. [61]

Animal management

Manure management

One of the main contributors to air, soil and water pollution is animal waste. According to a 2005 report by the USDA, more than 335–million tons of "dry matter" waste (the waste after water is removed) is produced annually on farms in the United States. [62] Animal feeding operations produce about 100 times more manure than the amount of human sewage sludge processed in US municipal waste water plants each year. Diffuse source pollution from agricultural fertilizers is more difficult to trace, monitor and control. High nitrate concentrations are found in groundwater and may reach 50 mg/litre (the EU Directive limit). In ditches and river courses, nutrient pollution from fertilizers causes eutrophication. This is worse in winter, after autumn ploughing has released a surge of nitrates; winter rainfall is heavier increasing runoff and leaching, and there is lower plant uptake. EPA suggests that one dairy farm with 2,500 cows produces as much waste as a city with around 411,000 residents. [63] The US National Research Council has identified odors as the most significant animal emission problem at the local level. Different animal systems have adopted several waste management procedures to deal with the large amount of waste produced annually.

The advantages of manure treatment are a reduction in the amount of manure that needs to be transported and applied to crops, as well as reduced soil compaction. Nutrients are reduced as well, meaning that less cropland is needed for manure to be spread upon. Manure treatment can also reduce the risk of human health and biosecurity risks by reducing the amount of pathogens present in manure. Undiluted animal manure or slurry is one hundred times more concentrated than domestic sewage, and can carry an intestinal parasite, Cryptosporidium, which is difficult to detect but can be passed to humans. Silage liquor (from fermented wet grass) is even stronger than slurry, with a low pH and very high biological oxygen demand. With a low pH, silage liquor can be highly corrosive; it can attack synthetic materials, causing damage to storage equipment, and leading to accidental spillage. All of these advantages can be optimized by using the right manure management system on the right farm based on the resources that are available.[ citation needed ]

Manure treatment

Composting

Composting is a solid manure management system that relies on solid manure from bedded pack pens, or the solids from a liquid manure separator. There are two methods of composting, active and passive. Manure is churned periodically during active composting, whereas in passive composting it is not. Passive composting has been found to have lower green house gas emissions due to incomplete decomposition and lower gas diffusion rates.[ citation needed ]

Solid-liquid separation

Manure can be mechanically separated into a solid and liquid portion for easier management. Liquids (4–8% dry matter) can be used easily in pump systems for convenient spread over crops and the solid fraction (15–30% dry matter) can be used as stall bedding, spread on crops, composted or exported.[ citation needed ]

Anaerobic digestion and lagoons
Anaerobic lagoon at a dairy Anaerobic Lagoon at Cal Poly.jpg
Anaerobic lagoon at a dairy

Anaerobic digestion is the biological treatment of liquid animal waste using bacteria in an area absent of air, which promotes the decomposition of organic solids. Hot water is used to heat the waste in order to increase the rate of biogas production. [64] The remaining liquid is nutrient rich and can be used on fields as a fertilizer and methane gas that can be burned directly on the biogas stove [65] or in an engine generator to produce electricity and heat. [64] [66] Methane is about 20 times more potent as a greenhouse gas than carbon dioxide, which has significant negative environmental effects if not controlled properly. Anaerobic treatment of waste is the best method for controlling the odor associated with manure management. [64]

Biological treatment lagoons also use anaerobic digestion to break down solids, but at a much slower rate. Lagoons are kept at ambient temperatures as opposed to the heated digestion tanks. Lagoons require large land areas and high dilution volumes to work properly, so they do not work well in many climates in the northern United States. Lagoons also offer the benefit of reduced odor and biogas is made available for heat and electric power. [67]

Studies have demonstrated that GHG emissions are reduced using aerobic digestion systems. GHG emission reductions and credits can help compensate for the higher installation cost of cleaner aerobic technologies and facilitate producer adoption of environmentally superior technologies to replace current anaerobic lagoons. [68]

See also

Related Research Articles

<span class="mw-page-title-main">Compost</span> Mixture used to improve soil fertility

Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical, and biological properties. It is commonly prepared by decomposing plant and food waste, recycling organic materials, and manure. The resulting mixture is rich in plant nutrients and beneficial organisms, such as bacteria, protozoa, nematodes, and fungi. Compost improves soil fertility in gardens, landscaping, horticulture, urban agriculture, and organic farming, reducing dependency on commercial chemical fertilizers. The benefits of compost include providing nutrients to crops as fertilizer, acting as a soil conditioner, increasing the humus or humic acid contents of the soil, and introducing beneficial microbes that help to suppress pathogens in the soil and reduce soil-borne diseases.

<span class="mw-page-title-main">Fertilizer</span> Substance added to soil to enhance plant growth

A fertilizer or fertiliser 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. 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.

<span class="mw-page-title-main">Intensive farming</span> Branch of agriculture

Intensive agriculture, also known as intensive farming, conventional, or industrial agriculture, is a type of agriculture, both of crop plants and of animals, with higher levels of input and output per unit of agricultural land area. It is characterized by a low fallow ratio, higher use of inputs such as capital, labour, agrochemicals and water, and higher crop yields per unit land area.

<span class="mw-page-title-main">Sustainable agriculture</span> Farming approach that balances environmental, economic and social factors in the long term

Sustainable agriculture is farming in sustainable ways meeting society's present food and textile needs, without compromising the ability for current or future generations to meet their needs. It can be based on an understanding of ecosystem services. There are many methods to increase the sustainability of agriculture. When developing agriculture within sustainable food systems, it is important to develop flexible business processes and farming practices. Agriculture has an enormous environmental footprint, playing a significant role in causing climate change, water scarcity, water pollution, land degradation, deforestation and other processes; it is simultaneously causing environmental changes and being impacted by these changes. Sustainable agriculture consists of environment friendly methods of farming that allow the production of crops or livestock without causing damage to human or natural systems. It involves preventing adverse effects on soil, water, biodiversity, and surrounding or downstream resources, as well as to those working or living on the farm or in neighboring areas. Elements of sustainable agriculture can include permaculture, agroforestry, mixed farming, multiple cropping, and crop rotation.

<span class="mw-page-title-main">Nutrient management</span> Management of nutrients in agriculture

Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place of nutrient application.

<span class="mw-page-title-main">Soil fertility</span> The ability of a soil to sustain agricultural plant growth

Soil fertility refers to the ability of soil to sustain agricultural plant growth, i.e. to provide plant habitat and result in sustained and consistent yields of high quality. It also refers to the soil's ability to supply plant/crop nutrients in the right quantities and qualities over a sustained period of time. A fertile soil has the following properties:

<span class="mw-page-title-main">Agricultural wastewater treatment</span> Farm management for controlling pollution from confined animal operations and surface runoff

Agricultural wastewater treatment is a farm management agenda for controlling pollution from confined animal operations and from surface runoff that may be contaminated by chemicals in fertilizer, pesticides, animal slurry, crop residues or irrigation water. Agricultural wastewater treatment is required for continuous confined animal operations like milk and egg production. It may be performed in plants using mechanized treatment units similar to those used for industrial wastewater. Where land is available for ponds, settling basins and facultative lagoons may have lower operational costs for seasonal use conditions from breeding or harvest cycles. Animal slurries are usually treated by containment in anaerobic lagoons before disposal by spray or trickle application to grassland. Constructed wetlands are sometimes used to facilitate treatment of animal wastes.

<span class="mw-page-title-main">Organic fertilizer</span> Fertilizer developed from natural processes

Organic fertilizers are fertilizers that are naturally produced. Fertilizers are materials that can be added to soil or plants, in order to provide nutrients and sustain growth. Typical organic fertilizers include all animal waste including meat processing waste, manure, slurry, and guano; plus plant based fertilizers such as compost; and biosolids. Inorganic "organic fertilizers" include minerals and ash. Organic refers to the Principles of Organic Agriculture, which determines whether a fertilizer can be used for commercial organic agriculture, not whether the fertilizer consists of organic compounds.

<span class="mw-page-title-main">Nonpoint source pollution</span> Pollution resulting from multiple sources

Nonpoint source (NPS) pollution refers to diffuse contamination of water or air that does not originate from a single discrete source. This type of pollution is often the cumulative effect of small amounts of contaminants gathered from a large area. It is in contrast to point source pollution which results from a single source. Nonpoint source pollution generally results from land runoff, precipitation, atmospheric deposition, drainage, seepage, or hydrological modification where tracing pollution back to a single source is difficult. Nonpoint source water pollution affects a water body from sources such as polluted runoff from agricultural areas draining into a river, or wind-borne debris blowing out to sea. Nonpoint source air pollution affects air quality, from sources such as smokestacks or car tailpipes. Although these pollutants have originated from a point source, the long-range transport ability and multiple sources of the pollutant make it a nonpoint source of pollution; if the discharges were to occur to a body of water or into the atmosphere at a single location, the pollution would be single-point.

<span class="mw-page-title-main">Biodegradable waste</span> Organic matter that can be broken down

Biodegradable waste includes any organic matter in waste which can be broken down into carbon dioxide, water, methane, compost, humus, and simple organic molecules by micro-organisms and other living things by composting, aerobic digestion, anaerobic digestion or similar processes. It mainly includes kitchen waste, ash, soil, dung and other plant matter. In waste management, it also includes some inorganic materials which can be decomposed by bacteria. Such materials include gypsum and its products such as plasterboard and other simple sulfates which can be decomposed by sulfate reducing bacteria to yield hydrogen sulfide in anaerobic land-fill conditions.

<span class="mw-page-title-main">Environmental impacts of animal agriculture</span> Impact of farming animals on the environment

The environmental impacts of animal agriculture vary because of the wide variety of agricultural practices employed around the world. Despite this, all agricultural practices have been found to have a variety of effects on the environment to some extent. Animal agriculture, in particular meat production, can cause pollution, greenhouse gas emissions, biodiversity loss, disease, and significant consumption of land, food, and water. Meat is obtained through a variety of methods, including organic farming, free-range farming, intensive livestock production, and subsistence agriculture. The livestock sector also includes wool, egg and dairy production, the livestock used for tillage, and fish farming.

In agriculture, leaching is the loss of water-soluble plant nutrients from the soil, due to rain and irrigation. Soil structure, crop planting, type and application rates of fertilizers, and other factors are taken into account to avoid excessive nutrient loss. Leaching may also refer to the practice of applying a small amount of excess irrigation where the water has a high salt content to avoid salts from building up in the soil. Where this is practiced, drainage must also usually be employed, to carry away the excess water.

The environmental impact of agriculture is the effect that different farming practices have on the ecosystems around them, and how those effects can be traced back to those practices. The environmental impact of agriculture varies widely based on practices employed by farmers and by the scale of practice. Farming communities that try to reduce environmental impacts through modifying their practices will adopt sustainable agriculture practices. The negative impact of agriculture is an old issue that remains a concern even as experts design innovative means to reduce destruction and enhance eco-efficiency. Animal agriculture practices tend to be more environmentally destructive than agricultural practices focused on fruits, vegetables and other biomass. The emissions of ammonia from cattle waste continue to raise concerns over environmental pollution.

<span class="mw-page-title-main">Nutrient pollution</span> Contamination of water by excessive inputs of nutrients

Nutrient pollution, a form of water pollution, refers to contamination by excessive inputs of nutrients. It is a primary cause of eutrophication of surface waters, in which excess nutrients, usually nitrogen or phosphorus, stimulate algal growth. Sources of nutrient pollution include surface runoff from farm fields and pastures, discharges from septic tanks and feedlots, and emissions from combustion. Raw sewage is a large contributor to cultural eutrophication since sewage is high in nutrients. Releasing raw sewage into a large water body is referred to as sewage dumping, and still occurs all over the world. Excess reactive nitrogen compounds in the environment are associated with many large-scale environmental concerns. These include eutrophication of surface waters, harmful algal blooms, hypoxia, acid rain, nitrogen saturation in forests, and climate change.

Agricultural microbiology is a branch of microbiology dealing with plant-associated microbes and plant and animal diseases. It also deals with the microbiology of soil fertility, such as microbial degradation of organic matter and soil nutrient transformations. The primary goal of agricultural microbiology is to comprehensively explore the interactions between beneficial microorganisms like bacteria and fungi with crops. It also deals with the microbiology of soil fertility, such as microbial degradation of organic matter and soil nutrient transformations.

Soil management is the application of operations, practices, and treatments to protect soil and enhance its performance. It includes soil conservation, soil amendment, and optimal soil health. In agriculture, some amount of soil management is needed both in nonorganic and organic types to prevent agricultural land from becoming poorly productive over decades. Organic farming in particular emphasizes optimal soil management, because it uses soil health as the exclusive or nearly exclusive source of its fertilization and pest control.

<span class="mw-page-title-main">Manure</span> Organic matter, mostly derived from animal feces, which can be used as fertilizer

Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutrients, such as nitrogen, that are utilised by bacteria, fungi and other organisms in the soil. Higher organisms then feed on the fungi and bacteria in a chain of life that comprises the soil food web.

<span class="mw-page-title-main">Reuse of human excreta</span> Safe, beneficial use of human excreta mainly in agriculture (after treatment)

Reuse of human excreta is the safe, beneficial use of treated human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated excreta may focus on using the plant-available nutrients that are contained in the treated excreta. They may also make use of the organic matter and energy contained in the excreta. To a lesser extent, reuse of the excreta's water content might also take place, although this is better known as water reclamation from municipal wastewater. The intended reuse applications for the nutrient content may include: soil conditioner or fertilizer in agriculture or horticultural activities. Other reuse applications, which focus more on the organic matter content of the excreta, include use as a fuel source or as an energy source in the form of biogas.

<span class="mw-page-title-main">Soil regeneration</span> Creation of new soil and rejuvenation of soil health

Soil regeneration, as a particular form of ecological regeneration within the field of restoration ecology, is creating new soil and rejuvenating soil health by: minimizing the loss of topsoil, retaining more carbon than is depleted, boosting biodiversity, and maintaining proper water and nutrient cycling. This has many benefits, such as: soil sequestration of carbon in response to a growing threat of climate change, a reduced risk of soil erosion, and increased overall soil resilience.

<span class="mw-page-title-main">Greenhouse gas emissions from agriculture</span>

The amount of greenhouse gas emissions from agriculture is significant: The agriculture, forestry and land use sectors contribute between 13% and 21% of global greenhouse gas emissions. Emissions come from direct greenhouse gas emissions. And from indirect emissions. With regards to direct emissions, nitrous oxide and methane makeup over half of total greenhouse gas emissions from agriculture. Indirect emissions on the other hand come from the conversion of non-agricultural land such as forests into agricultural land. Furthermore, there is also fossil fuel consumption for transport and fertilizer production. For example, the manufacture and use of nitrogen fertilizer contributes around 5% of all global greenhouse gas emissions. Livestock farming is a major source of greenhouse gas emissions. At the same time, livestock farming is affected by climate change.

References

  1. ↑ "Agricultural Nonpoint Source Fact Sheet". United States Environmental Protection Agency. EPA. 2015-02-20. Retrieved 22 April 2015.
  2. ↑ "Investigating the Environmental Effects of Agriculture Practices on Natural Resources". USGS. January 2007, pubs.usgs.gov/fs/2007/3001/pdf/508FS2007_3001.pdf. Accessed 2 April 2018.
  3. ↑ IPCC (2019). Shukla, P.R.; Skea, J.; Calvo Buendia, E.; Masson-Delmotte, V.; et al. (eds.). IPCC Special Report on Climate Change, polution Desertification, Land Degradation, Sustainable Land Management, Food Security, and Greenhouse gas fluxes in Terrestrial Ecosystems (PDF). In press. https://www.ipcc.ch/report/srccl/.
  4. 1 2 "Actions on Air Quality. A Global Summary of Policies and Programmes to Reduce Air Pollution". United Nations Environment Programme. 2024.
  5. ↑ Stefanovic, Lilliana; Freytag-Leyer, Barbara; Kahl, Johannes (2020). "Food System Outcomes: An Overview and the Contribution to Food Systems Transformation". Frontiers in Sustainable Food Systems. 4. doi: 10.3389/fsufs.2020.546167 . ISSN   2571-581X.
  6. ↑ Leip, Adrian; Bodirsky, Benjamin Leon; Kugelberg, Susanna (1 March 2021). "The role of nitrogen in achieving sustainable food systems for healthy diets". Global Food Security. 28: 100408. Bibcode:2021GlFS...2800408L. doi:10.1016/j.gfs.2020.100408. PMC   7938701 . PMID   33738182.
  7. ↑ Allievi, Francesca; Antonelli, Marta; Dembska, Katarzyna; Principato, Ludovica (2019). "Understanding the Global Food System". Achieving the Sustainable Development Goals Through Sustainable Food Systems. pp. 3–23. doi:10.1007/978-3-030-23969-5_1. ISBN   978-3-030-23968-8.
  8. ↑ Canada, Agriculture and Agri-Food (2014-07-18). "Agriculture and water quality". agriculture.canada.ca. Retrieved 2024-04-12.
  9. ↑ "Agricultural technology - Pesticides, Herbicides, Fertilizers | Britannica". www.britannica.com. Retrieved 2024-04-12.
  10. ↑ "Environmental Databases: Ecotoxicity Database". Pesticides: Science and Policy. Washington, D.C.: U.S. Environmental Protection Agency (EPA). 2006-06-28. Archived from the original on 2014-07-04.
  11. ↑ Canada, Agriculture and Agri-Food (2014-07-18). "Agriculture and water quality". agriculture.canada.ca. Retrieved 2024-04-12.
  12. 1 2 3 4 5 6 Gullan, P. J.; Cranston, P. S. (2010). The Insects: An Outline of Entomology. John Wiley & Sons. ISBN   978-1-4443-1767-1.[ page needed ]
  13. 1 2 3 4 L. P. Pedigo, and M. Rice. 2009. Entomology and Pest Management, 6th Edition. Prentice Hall: 816 pp.[ page needed ]
  14. ↑ Montesinos, Emilio (December 2003). "Development, registration and commercialization of microbial pesticides for plant protection". International Microbiology. 6 (4): 245–252. doi:10.1007/s10123-003-0144-x. PMID   12955583.
  15. ↑ "Environmental Fate of Pesticides". Pesticide Wise. Victoria, BC: British Columbia Ministry of Agriculture. Archived from the original on 2015-12-25.
  16. ↑ Smil, Vaclav (2011). "Nitrogen cycle and world food production" (PDF). World Agriculture. 2: 9–13.
  17. ↑ "A quick look at the nitrogen cycle and nitrogen fertilizer sources – Part 1". MSU Extension. February 2017. Retrieved 2020-04-10.
  18. ↑ Ward, Mary H.; Jones, Rena R.; Brender, Jean D.; de Kok, Theo M.; Weyer, Peter J.; Nolan, Bernard T.; Villanueva, Cristina M.; van Breda, Simone G. (July 2018). "Drinking Water Nitrate and Human Health: An Updated Review". International Journal of Environmental Research and Public Health. 15 (7): 1557. doi: 10.3390/ijerph15071557 . ISSN   1661-7827. PMC   6068531 . PMID   30041450.
  19. ↑ Bernhard, Anne (2010). "The Nitrogen Cycle: Processes, Players, and Human Impact". Nature Education Knowledge. 3 (10): 25.
  20. ↑ Diaz, Robert; Rosenberg, Rutger (2008-08-15). "Spreading Dead Zones and Consequences for Marine Ecosystems". Science. 321 (5891): 926–929. Bibcode:2008Sci...321..926D. doi:10.1126/science.1156401. PMID   18703733. S2CID   32818786.
  21. ↑ Erisman, Jan Willem; Galloway, James N.; Seitzinger, Sybil; Bleeker, Albert; Dise, Nancy B.; Petrescu, A. M. Roxana; Leach, Allison M.; de Vries, Wim (2013-07-05). "Consequences of human modification of the global nitrogen cycle". Philosophical Transactions of the Royal Society B: Biological Sciences. 368 (1621): 20130116. doi:10.1098/rstb.2013.0116. ISSN   0962-8436. PMC   3682738 . PMID   23713116.
  22. ↑ Weese, Dylan J.; Heath, Katy D.; Dentinger, Bryn T. M.; Lau, Jennifer A. (2015-02-05). "Long-term nitrogen addition causes the evolution of less-cooperative mutualists". Evolution. 69 (3): 631–642. doi:10.1111/evo.12594. ISSN   0014-3820.
  23. ↑ Lu, Chaoqun; Tian, Hanqin (2 March 2017). "Global nitrogen and phosphorus fertilizer use for agriculture production in the past half century: shifted hot spots and nutrient imbalance". Earth System Science Data. 9 (1): 181–192. Bibcode:2017ESSD....9..181L. doi: 10.5194/essd-9-181-2017 .
  24. ↑ "Understanding phosphorus fertilizers". extension.umn.edu. Retrieved 2020-04-09.
  25. ↑ Hart, Murray R.; Quin, Bert F.; Nguyen, M. Long (November 2004). "Phosphorus Runoff from Agricultural Land and Direct Fertilizer Effects: A Review". Journal of Environmental Quality. 33 (6): 1954–1972. Bibcode:2004JEnvQ..33.1954H. doi:10.2134/jeq2004.1954. PMID   15537918.
  26. ↑ "Managing Phosphorus for Agriculture and the Environment (Pennsylvania Nutrient Management Program)". Pennsylvania Nutrient Management Program (Penn State Extension). Archived from the original on 2019-06-07. Retrieved 2020-04-09.
  27. ↑ US EPA, OW (2013-11-27). "Indicators: Phosphorus". US EPA. Retrieved 2020-04-19.
  28. ↑ US EPA, OW (2013-03-12). "The Effects: Dead Zones and Harmful Algal Blooms". US EPA. Retrieved 2020-04-10.
  29. ↑ Mar, Swe Swe; Okazaki, Masanori (September 2012). "Investigation of Cd contents in several phosphate rocks used for the production of fertilizer". Microchemical Journal. 104: 17–21. doi:10.1016/j.microc.2012.03.020.
  30. ↑ Ochoa-Herrera, Valeria; Banihani, Qais; León, Glendy; Khatri, Chandra; Field, James A.; Sierra-Alvarez, Reyes (July 2009). "Toxicity of fluoride to microorganisms in biological wastewater treatment systems". Water Research. 43 (13): 3177–3186. Bibcode:2009WatRe..43.3177O. doi:10.1016/j.watres.2009.04.032. PMID   19457531.
  31. ↑ Technology, International Environmental. "5 Types of Agricultural Pollution". Envirotech Online. Retrieved 2024-04-12.
  32. ↑ Committee on Long-Range Soil and Water Conservation, National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. National Academy Press: Washington, D.C.[ page needed ]
  33. ↑ Dudal, R. (1981). "An evaluation of conservation needs". In Morgan, R. P. C. (ed.). Soil Conservation, Problems and Prospects. Chichester, U.K.: Wiley. pp. 3–12.
  34. ↑ Abrantes, Nelson; Pereira, Ruth; Gonçalves, Fernando (2010-01-30). "Occurrence of Pesticides in Water, Sediments, and Fish Tissues in a Lake Surrounded by Agricultural Lands: Concerning Risks to Humans and Ecological Receptors". Water, Air, & Soil Pollution. 212 (1–4). Springer Science and Business Media LLC: 77–88. Bibcode:2010WASP..212...77A. doi:10.1007/s11270-010-0323-2. ISSN   0049-6979. S2CID   93206521.
  35. ↑ MacKenzie, A. F; Fan, M. X; Cadrin, F (1998). "Nitrous Oxide Emission in Three Years as Affected by Tillage, Corn-Soybean-Alfalfa Rotations, and Nitrogen Fertilization". Journal of Environmental Quality. 27 (3): 698–703. Bibcode:1998JEnvQ..27..698M. doi:10.2134/jeq1998.00472425002700030029x.
  36. ↑ Reeve, J. R.; Hoagland, L. A.; Villalba, J. J.; Carr, P. M.; Atucha, A.; Cambardella, C.; Davis, D. R.; Delate, K. (1 January 2016). "Chapter Six – Organic Farming, Soil Health, and Food Quality: Considering Possible Links". Advances in Agronomy. 137. Academic Press: 319–367. doi:10.1016/bs.agron.2015.12.003.
  37. ↑ Tully, Katherine L.; McAskill, Cullen (1 September 2020). "Promoting soil health in organically managed systems: a review". Organic Agriculture. 10 (3): 339–358. Bibcode:2020OrgAg..10..339T. doi:10.1007/s13165-019-00275-1. ISSN   1879-4246. S2CID   209429041.
  38. ↑ M. Tahat, Monther; M. Alananbeh, Kholoud; A. Othman, Yahia; I. Leskovar, Daniel (January 2020). "Soil Health and Sustainable Agriculture". Sustainability. 12 (12): 4859. doi: 10.3390/su12124859 .
  39. ↑ Brian Moss (12 February 2008). "Water pollution by agriculture". Philos Trans R Soc Lond B Biol Sci. 363 (1491): 659–66. doi:10.1098/rstb.2007.2176. PMC   2610176 . PMID   17666391.
  40. ↑ "Social, Cultural, Institutional and Economic Aspects of Eutrophication". UNEP . Retrieved 14 October 2018.
  41. ↑ Aktar; et al. (March 2009). "Impact of pesticides use in agriculture: their benefits and hazards". Interdiscip Toxicol. 2 (1): 1–12. doi:10.2478/v10102-009-0001-7. PMC   2984095 . PMID   21217838.
  42. ↑ Sharon Oosthoek (17 June 2013). "Pesticides spark broad biodiversity loss". Nature. doi: 10.1038/nature.2013.13214 . S2CID   130350392 . Retrieved 14 October 2018.
  43. 1 2 Seufert, Verena; Ramankutty, Navin (2017). "Many shades of gray — The context-dependent performance of organic agriculture". Science Advances. 3 (3): e1602638. Bibcode:2017SciA....3E2638S. doi:10.1126/sciadv.1602638. ISSN   2375-2548. PMC   5362009 . PMID   28345054.
  44. ↑ "Organic meats found to have approximately the same greenhouse impact as regular meats". phys.org. Retrieved 31 December 2020.
  45. 1 2 Pieper, Maximilian; Michalke, Amelie; Gaugler, Tobias (15 December 2020). "Calculation of external climate costs for food highlights inadequate pricing of animal products". Nature Communications. 11 (1): 6117. Bibcode:2020NatCo..11.6117P. doi:10.1038/s41467-020-19474-6. ISSN   2041-1723. PMC   7738510 . PMID   33323933.
  46. ↑ Smith, Laurence G.; Kirk, Guy J. D.; Jones, Philip J.; Williams, Adrian G. (22 October 2019). "The greenhouse gas impacts of converting food production in England and Wales to organic methods". Nature Communications. 10 (1): 4641. Bibcode:2019NatCo..10.4641S. doi:10.1038/s41467-019-12622-7. PMC   6805889 . PMID   31641128.
  47. ↑ "Conservation Agriculture". www.fao.org. Food and Agriculture Organization of the United Nations. Retrieved 2024-09-04.
  48. ↑ Kassam, A.; Friedrich, T.; Derpsch, R. (2019-01-02). "Global spread of Conservation Agriculture". International Journal of Environmental Studies. 76 (1): 29–51. Bibcode:2019IJEnS..76...29K. doi:10.1080/00207233.2018.1494927. ISSN   0020-7233.
  49. ↑ "Conservation Agriculture". Conservation Agriculture (factsheet). 1 March 2022.
  50. ↑ "Sewage Sludge Surveys". Biosolids. EPA. 2016-08-17.
  51. ↑ Pitesky, Maurice E; Stackhouse, Kimberly R; Mitloehner, Frank M (2009). "Clearing the Air: Livestock's Contribution to Climate Change". Advances in Agronomy. Vol. 103. pp. 1–40. doi:10.1016/S0065-2113(09)03001-6. ISBN   978-0-12-374819-5.
  52. ↑ Robert Goodland; Jeff Anhang (November–December 2009). "Livestock and climate change: what if the key actors in climate change are... cows, pigs, and chickens?" (PDF). World Watch. Archived from the original (PDF) on 2009-11-05.
  53. ↑ Dopelt, Keren; Radon, Pnina; Davidovitch, Nadav (April 16, 2019). "Environmental Effects of the Livestock Industry: The Relationship between Knowledge, Attitudes, and Behavior among Students in Israel". International Journal of Environmental Research and Public Health. 16 (8): 1359. doi: 10.3390/ijerph16081359 . PMC   6518108 . PMID   31014019.
  54. ↑ White, Robin R.; Hall, Mary Beth (Nov 13, 2017). "Nutritional and greenhouse gas impacts of removing animals from US agriculture". Proceedings of the National Academy of Sciences. 114 (48): E10301–E10308. Bibcode:2017PNAS..11410301W. doi: 10.1073/pnas.1707322114 . PMC   5715743 . PMID   29133422.
  55. 1 2 Mooney, H. A; Cleland, E. E (2001). "The evolutionary impact of invasive species". Proceedings of the National Academy of Sciences. 98 (10): 5446–51. Bibcode:2001PNAS...98.5446M. doi: 10.1073/pnas.091093398 . PMC   33232 . PMID   11344292.
  56. ↑ Kevan, P.G. (2008). "Bombus franklini". IUCN Red List of Threatened Species . 2008: e.T135295A4070259. doi: 10.2305/IUCN.UK.2008.RLTS.T135295A4070259.en . Retrieved 31 May 2024.
  57. ↑ Thorp, R.W.; Shepherd, M.D. (2005). "Profile: Subgenus Bombus Lateille 1802 (Apidae: Apinae: Bombini)". In Shepherd, M.D.; Vaughan, D.M.; Black, S.H. (eds.). Red list of pollinator insects of North America. Portland, OR: Xerces Society for Invertebrate Conservation.[ page needed ]
  58. ↑ "Weeds in Australia home page". Weeds.gov.au. 2013-06-12. Retrieved 2013-07-24.[ permanent dead link ]
  59. ↑ Louda, S.M.; Pemberton, R.W.; Johnson, M.T.; Follett, P.A. (January 2003). "Nontarget effects—the Achilles' heel of biological control? Retrospective analyses to reduce risk associated with biocontrol introductions". Annual Review of Entomology. 48 (1): 365–396. doi:10.1146/annurev.ento.48.060402.102800. PMID   12208812.
  60. ↑ Ghag, Siddhesh B. (2024). "Genetically modified organisms and their regulatory frameworks". Global Regulatory Outlook for CRISPRized Plants. pp. 147–166. doi:10.1016/B978-0-443-18444-4.00023-5. ISBN   978-0-443-18444-4.
  61. ↑ Golovan, Serguei P; Meidinger, Roy G; Ajakaiye, Ayodele; Cottrill, Michael; Wiederkehr, Miles Z; Barney, David J; Plante, Claire; Pollard, John W; Fan, Ming Z; Hayes, M. Anthony; Laursen, Jesper; Hjorth, J. Peter; Hacker, Roger R; Phillips, John P; Forsberg, Cecil W (2001). "Pigs expressing salivary phytase produce low-phosphorus manure". Nature Biotechnology. 19 (8): 741–5. doi:10.1038/90788. PMID   11479566. S2CID   52853680.
  62. ↑ USDA Agricultural Research Service. "FY-2005 Annual Report Manure and Byproduct Utilization", 31 May 2006
  63. ↑ Risk Management Evaluation for Concentrated Animal Feeding Operations (Report). Cincinnati, OH: EPA. May 2004. p. 7. EPA 600/R-04/042.
  64. 1 2 3 Evaluating the Need for a Manure Treatment System (PDF) (Report). Fact Sheet. Ithaca, NY: Cornell University Manure Management Program. 2005-04-12. MT-1.
  65. ↑ Roubík, Hynek; Mazancová, Jana; Phung, Le Dinh; Banout, Jan (2018). "Current approach to manure management for small-scale Southeast Asian farmers - Using Vietnamese biogas and non-biogas farms as an example". Renewable Energy. 115: 362–70. Bibcode:2018REne..115..362R. doi:10.1016/j.renene.2017.08.068.
  66. ↑ Animal Agriculture: Waste Management Practices (PDF) (Report). Washington, D.C.: U.S. General Accounting Office. July 1999. pp. 9–11. GAO/RCED-99-205. Archived from the original (PDF) on 2021-02-27. Retrieved 2012-03-05.
  67. ↑ Anaerobic Lagoons (PDF) (Report). Wastewater Technology Fact Sheet. EPA. September 2002. EPA 832-F-02-009.
  68. ↑ Vanotti, M.B; Szogi, A.A; Vives, C.A (2008). "Greenhouse gas emission reduction and environmental quality improvement from implementation of aerobic waste treatment systems in swine farms". Waste Management. 28 (4): 759–66. Bibcode:2008WaMan..28..759V. doi:10.1016/j.wasman.2007.09.034. PMID   18060761.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.