Environmental effects Fertilizer

1 environmental effects

1.1 water

1.1.1 nitrate pollution


1.2 soil

1.2.1 acidification
1.2.2 accumulation of toxic elements

1.2.2.1 cadmium
1.2.2.2 fluoride
1.2.2.3 radioactive elements
1.2.2.4 other metals


1.2.3 trace mineral depletion
1.2.4 changes in soil biology


1.3 energy consumption , sustainability

1.3.1 contribution climate change


1.4 atmosphere
1.5 regulation

environmental effects

runoff of soil , fertilizer during rain storm



an algal bloom caused eutrophication



water

agricultural run-off major contributor eutrophication of fresh water bodies. example, in us, half of lakes eutrophic. main contributor eutrophication phosphate, limiting nutrient; high concentrations promote growth of cyanobacteria , algae, demise of consumes oxygen. cyanobacteria blooms ( algal blooms ) can produce harmful toxins can accumulate in food chain, , can harmful humans.

the nitrogen-rich compounds found in fertilizer runoff primary cause of serious oxygen depletion in many parts of oceans, in coastal zones, lakes , rivers. resulting lack of dissolved oxygen reduces ability of these areas sustain oceanic fauna. number of oceanic dead zones near inhabited coastlines increasing. of 2006, application of nitrogen fertilizer being increasingly controlled in northwestern europe , united states. if eutrophication can reversed, may take decades before accumulated nitrates in groundwater can broken down natural processes.

nitrate pollution

only fraction of nitrogen-based fertilizers converted produce , other plant matter. remainder accumulates in soil or lost run-off. high application rates of nitrogen-containing fertilizers combined high water solubility of nitrate leads increased runoff surface water leaching groundwater, thereby causing groundwater pollution. excessive use of nitrogen-containing fertilizers (be synthetic or natural) particularly damaging, of nitrogen not taken plants transformed nitrate leached.

nitrate levels above 10 mg/l (10 ppm) in groundwater can cause blue baby syndrome (acquired methemoglobinemia). nutrients, nitrates, in fertilizers can cause problems natural habitats , human health if washed off soil watercourses or leached through soil groundwater.

soil
acidification

nitrogen-containing fertilizers can cause soil acidification when added. may lead decreases in nutrient availability may offset liming.

accumulation of toxic elements
cadmium

the concentration of cadmium in phosphorus-containing fertilizers varies considerably , can problematic. example, mono-ammonium phosphate fertilizer may have cadmium content of low 0.14 mg/kg or high 50.9 mg/kg. because phosphate rock used in manufacture can contain as 188 mg/kg cadmium (examples deposits on nauru , christmas islands). continuous use of high-cadmium fertilizer can contaminate soil (as shown in new zealand) , plants. limits cadmium content of phosphate fertilizers has been considered european commission. producers of phosphorus-containing fertilizers select phosphate rock based on cadmium content.

fluoride

phosphate rocks contain high levels of fluoride. consequently, widespread use of phosphate fertilizers has increased soil fluoride concentrations. has been found food contamination fertilizer of little concern plants accumulate little fluoride soil; of greater concern possibility of fluoride toxicity livestock ingest contaminated soils. of possible concern effects of fluoride on soil microorganisms.

radioactive elements

the radioactive content of fertilizers varies considerably , depends both on concentrations in parent mineral , on fertilizer production process. uranium-238 concentrations can range 7 100 pci/g in phosphate rock , 1 67 pci/g in phosphate fertilizers. high annual rates of phosphorus fertilizer used, can result in uranium-238 concentrations in soils , drainage waters several times greater present. however, impact of these increases on risk human health radinuclide contamination of foods small (less 0.05 msv/y).

other metals

steel industry wastes, recycled fertilizers high levels of zinc (essential plant growth), wastes can include following toxic metals: lead arsenic, cadmium, chromium, , nickel. common toxic elements in type of fertilizer mercury, lead, , arsenic. these potentially harmful impurities can removed; however, increases cost. highly pure fertilizers available , perhaps best known highly water-soluble fertilizers containing blue dyes used around households, such miracle-gro. these highly water-soluble fertilizers used in plant nursery business , available in larger packages @ less cost retail quantities. there inexpensive retail granular garden fertilizers made high purity ingredients.

trace mineral depletion

attention has been addressed decreasing concentrations of elements such iron, zinc, copper , magnesium in many foods on last 50–60 years. intensive farming practices, including use of synthetic fertilizers suggested reasons these declines , organic farming suggested solution. although improved crop yields resulting npk fertilizers known dilute concentrations of other nutrients in plants, of measured decline can attributed use of progressively higher-yielding crop varieties produce foods lower mineral concentrations less productive ancestors. is, therefore, unlikely organic farming or reduced use of fertilizers solve problem; foods high nutrient density posited achieved using older, lower-yielding varieties or development of new high-yield, nutrient-dense varieties.

fertilizers are, in fact, more solve trace mineral deficiency problems cause them: in western australia deficiencies of zinc, copper, manganese, iron , molybdenum identified limiting growth of broad-acre crops , pastures in 1940s , 1950s. soils in western australia old, highly weathered , deficient in many of major nutrients , trace elements. since time these trace elements routinely added fertilizers used in agriculture in state. many other soils around world deficient in zinc, leading deficiency in both plants , humans, , zinc fertilizers used solve problem.

changes in soil biology

high levels of fertilizer may cause breakdown of symbiotic relationships between plant roots , mycorrhizal fungi.

energy consumption , sustainability

in usa in 2004, 317 billion cubic feet of natural gas consumed in industrial production of ammonia, less 1.5% of total u.s. annual consumption of natural gas. 2002 report suggested production of ammonia consumes 5% of global natural gas consumption, under 2% of world energy production.

ammonia produced natural gas , air. cost of natural gas makes 90% of cost of producing ammonia. increase in price of natural gases on past decade, along other factors such increasing demand, have contributed increase in fertilizer price.

contribution climate change

the greenhouse gases carbon dioxide, methane , nitrous oxide produced during manufacture of nitrogen fertilizer. effects can combined equivalent amount of carbon dioxide. amount varies according efficiency of process. figure united kingdom on 2 kilogrammes of carbon dioxide equivalent each kilogramme of ammonium nitrate. nitrogen fertilizer can converted soil bacteria nitrous oxide, greenhouse gas.

atmosphere

global methane concentrations (surface , atmospheric) 2005; note distinct plumes

through increasing use of nitrogen fertilizer, used @ rate of 110 million tons (of n) per year in 2012, adding existing amount of reactive nitrogen, nitrous oxide (n2o) has become third important greenhouse gas after carbon dioxide , methane. has global warming potential 296 times larger equal mass of carbon dioxide , contributes stratospheric ozone depletion. changing processes , procedures, possible mitigate some, not all, of these effects on anthropogenic climate change.

methane emissions crop fields (notably rice paddy fields) increased application of ammonium-based fertilizers. these emissions contribute global climate change methane potent greenhouse gas.

regulation

in europe problems high nitrate concentrations in run-off being addressed european union s nitrates directive. within britain, farmers encouraged manage land more sustainably in catchment-sensitive farming . in us, high concentrations of nitrate , phosphorus in runoff , drainage water classified non-point source pollutants due diffuse origin; pollution regulated @ state level. oregon , washington, both in united states, have fertilizer registration programs on-line databases listing chemical analyses of fertilizers.