Difference between revisions of "What causes eutrophication?"

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==Introduction==
 
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[[Image:Naturalrunoff.jpg|thumb|right|150px|<small>Natural eutrophication</small>]]
 
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The main causes of eutrophication are''' an increase in the concentration of nutrients''' in an ecosystem. A distinction is sometimes made between 'natural' and 'cultural' ([[anthropogenic]]) eutrophication processes.
 
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'''Natural eutrophication''' has been occurring for millennia. It is the process of addition of [[nutrients]] to water bodies, including lakes, rivers, estuaries and oceans resulting in changes to the primary production and species composition of the community. This process occurs over extended periods of time that are typically geological time scales. [[Image:Fertilizerrunoff.jpg|thumb|right|150px|<small>Cultural eutrophication (use of fertilizers in agriculture)</small>]]
 
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'''Cultural eutrophication''' is the process that speeds up natural eutrophication because of human activity.
 
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These activities come from many diverse sources including agriculture, [[agriculture]], septic tanks, urban wastewater, urban stormwater runoff, industry, and fossil fuel combustion. Nutrients such as phosphates and nitrates enter aquatic ecosystems via the air, surface water, or groundwater.
 
  
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==Trophic status==
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{{ Definition| title = Eutrophication
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| definition = The (mostly undesired) increase in the concentration of [[nutrient]]s in an ecosystem.}}
  
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<div style="text-align: left; direction: ltr; margin-left: 1em;">
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==Causes of eutrophication==
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The stage at which the process of eutrophication is at any given time in a particular water body is useful to describe the status of the water body. The following terms are used:
 
  
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''Oligotrophic''
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[[Image:SewageEffluentDenver.jpg|350px|thumb|right|<small>Discharge of Denver sewage treatment plant in the Platte River (USA). Photo credit: Jeffrey Beall (2008)</small>]]
  
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Low in nutrients and not productive in terms of aquatic animal and plant life.
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===Supply of [[nutrient]]s===
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A major cause of eutrophication is the increased nutrient enrichment that can arise from both '''point''' and '''non-point sources''' (also called 'diffusive pollution sources'):
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* '''Point source pollution''': Pollution that comes from contaminants that enter a waterway from a single identifiable source such as stationary locations or fixed facilities. Examples are discharges from a sewage treatment plant (Fig. 1) or industrial plants and fish farms.
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* '''Non-point source pollution''': Pollution from widespread including human activities with no specific point of discharge or entry into receiving watercourses. Examples are leaching out of nitrogen compounds from fertilized agricultural lands (Fig. 2) and losses from atmospheric deposition.  
  
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''Mesotrophic''
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[[Image:manure_run-off.jpg|350px|right|thumb|<small>Manure run-off, an example of non-point source pollution (Photo credit: Chris Court)</small>]]
  
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Intermediate levels of nutrients, fairly productive in terms of aquatic animal and plant life and showing emerging signs of water quality problems
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The enrichment of water by nutrients can be of a '''natural origin''' (natural eutrophication) but is often dramatically increased by '''human activities''' (cultural or [[Anthropogenic|anthropogenic]] eutrophication). '''Natural eutrophication''' has been occurring for millennia<ref>De Jonge, V.N., Elliot, M. and Orive, E. 2002. Causes, historical development, effects and future challenges of a common environmental problem: eutrophication. Hydrobiologia 475-476: 1-19</ref>. It is the process of addition, flow and accumulation of nutrients to water bodies resulting in changes to the [[primary production]] and species composition of the community. Main processes  '''Cultural eutrophication''' is the process that speeds up natural eutrophication because of human activity. There are a few main sources of anthropogenic nutrient input: erosion and leaching from fertilized agricultural areas, sewage from cities and industrial waste water. Atmospheric deposition of nitrogen (from animal breeding and combustion gases) can also be important<ref>EEA, 2005. Source apportionment of nitrogen and phosphorus inputs into the aquatic environment. European Environment Agency Report 7, Office for Official Publications of the European Communities: Luxembourg. ISBN 92-9167-777-9. 48 pp</ref>. Globally, it is estimated that in 2017 more than 80 % of sewage was released into the environment without any treatment<ref name=T21>Tuholske, C., Halpern, B.S., Blasco, G., Villasenor, J.C., Frazier, M. and Caylor, K. 2021. Mapping global inputs and impacts from of human sewage in coastal ecosystems. PLoS ONE 16(11),  e0258898</ref>.
  
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''Eutrophic''
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===Other causes of eutrophication===
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[[Image:lake.png|thumb|right|300px|<small>Example of an eutrophic lake</small>]]
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An increase in the concentration of nutrients can also have other causes.
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Rich in nutrients, very productive in terms of aquatic animal and plant life and showing increasing signs of water quality problems
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* Reduced flushing. When flushing is reduced, the retention time of nutrients entering the water body is increased. This leads to an increase in the nutrient concentration in cases where the flushing waters are not the main nutrient suppliers. Examples are coastal lagoons in urbanized zones flushed by river runoff or by tidal action. Drought, water diversion or temporary closure of the sea inlet are possible causes of reduced flushing<ref name=M23>Mosley, L.M., Priestley, S., Brookes, J., Dittmann, S., Farkas, J., Farrell, M., Ferguson, A.J., Gibbs, M., Hipsey, M., Huang, J., Lam-Gordillo, O., Simpson, S.L., Tyler, J.J., Waycott, M. and Welsh, D.T. 2023. Extreme eutrophication and salinisation in the Coorong estuarine-lagoon ecosystem of Australia's largest river basin (Murray-Darling). Marine Pollution Bulletin 188, 114648</ref>.
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* Reduced nutrient removal. Changes in environmental conditions can cause the degradation or loss of ecosystem components capable to remove nutrients. Examples are changes in salinity, turbidity or temperature detrimental to benthic fauna and flora communities, which previously promoted nutrient sequestration (e.g., peat formation) and elimination processes (e.g., denitrification). This can lead to substantial accumulation of organic matter and nutrients within the sediment, promoting anoxic, sulfide-rich conditions and high recycling of nutrients back to the water column<ref name=M23/>.
  
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''Hypertrophic''
 
  
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Very high nutrient concentrations where plant growth is determined by physical factors. Water quality problems are serious and almost continuous.
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==Eutrophicating nutrients==
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The most common nutrients causing eutrophication are [[nitrogen]] N and [[phosphorus]] P. The main source of nitrogen pollutants is run-off from agricultural land, whereas most phosphorus pollution comes from households and industry, including phosphorus-based detergents. These nutrients enter aquatic ecosystems via the air, surface water or groundwater. Most of the commercially fixed nitrogen and mined phosphorus goes into production of [[fertilizer]]. The rising demand for fertilizer has come from the need to meet the nutritional demands of our rapidly expanding human population. The rise in intensive fertilizer use has serious implications for coastal habitats because greater application results in greater runoff, and the fraction of fertilizer lost from fields will increase with intensity of application. Increased global production of nitrogenous fertilizers have largely been linked to concerns over the relationship between water quality and eutrophication. Nutrient removal in sewage treatment plants and promotion of phosphorus-free detergents are vital to minimize the impact of nitrogen and phosphorus pollution in Europe's waters<ref>EC, 2002.  Eutrophication and health. European Commission, Office for Official Publications of the European Communities: Luxembourg. ISBN 92-894-4413-4. 28 pp</ref>.
  
  
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== References ==
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==Some quantitative estimates==
  
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Walmsley RD, 2000. A Review and Discussion Document. Perspectives on Eutrophication of
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The emissions of N and P to the coastal ocean have doubled during the past century. More than half of these emissions are related to agriculture<ref name=LM>Le Moal, M., Gascuel-Odoux, C., Menesguen, A., Souchon, Y., Etrillard, C., Levain, A., Moatar, F., Pannard, A., Souchu, P., Lefebvre, A. and Pinay, G. 2019. Eutrophication: A new wine in an old bottle? Science of the Total Environment 651: 1-11</ref>. In 2020, the global annual production of anthropogenic reactive N (mainly ammonia, urea, nitrate) was in the order of 260 Tg N (=260 million tons N), of which 160 Tg is produced synthetically from natural gas through the so-called [https://en.wikipedia.org/wiki/Haber_process Haber-Bosch process] (120 Tg used as fertilizer), 25-40 Tg  comes from fossil fuels, 30-35 Tg from N fixation by cultivated crops and rice, 15-20 Tg from animal manure, 6-10 Tg from sewage and 2-3 Tg from mariculture<ref name=MN>Malone, T.C. and Newton, A. 2020. The Globalization of Cultural Eutrophication in the Coastal Ocean: Causes and Consequences. Front. Mar. Sci. 7:670</ref><ref name=T21/><ref name=P>Penuelas, J., Poulter, B., Sardans, J., Ciais, P., van der Velde, M., Bopp, L., et al. 2013. Human-induced nitrogen–phosphorus imbalances alter natural and managed ecosystems across the globe. Nat. Commun. 4: 2934</ref><ref name=L>Lu, C. and Tian, H. 2017. Global nitrogen and phosphorus fertilizer use for agriculture production in the past half century: shifted hot spots and nutrient imbalance. Earth Syst. Sci. Data 9, 181–192</ref><ref name=FAO>FAO. 2019. World fertilizer trends and outlook to 2022. Rome</ref>.  About one quarter of this production finds its way (mainly through river runoff and atmospheric deposition) to the coastal ocean<ref name=MN/>, which receives an annual load in the order of 50 Tg N/yr <ref name=B15>Beusen, A. H. W., Bouwman, A. F., Van Beek, L. P. H., Mogollón, J. M. and Middelburg, J.J. 2015. Global riverine N and P transport to ocean increased during the twentieth century despite increased retention along the aquatic continuum. Biogeosciences Discuss. 12: 20123–20148</ref><ref name=MN>Malone, T.C. and Newton, A. 2020. The Globalization of Cultural Eutrophication in the Coastal Ocean: Causes and Consequences. Front. Mar. Sci. 7: 670 </ref>. China is by far the greatest user of N fertilizer, taking 31 % of the total share. Other important users are India, USA, Europe, Brazil and Pakistan (see Fig. 3).
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Surface Waters: Policy/Research Needs in South Africa. Water Research Commission. Project
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K8/360
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The annual global anthropogenic production of mineral phosphorus P in 2020 is estimated at about 20 Tg P <ref name=FAO/>, almost entirely based on mining of phosphate rock. When the use of livestock slurry and manure is included, the total phosphorus application in agriculture amounts to 25–29 Tg P per year<ref name=P/>. It is estimated that 5-8.6 Tg P is flushed to the coastal ocean<ref>Seitzinger, S.P., Mayorga, E., Bouwman, A.F., Kroeze, C., Beusen, A.H.W., Billen, G., Van Drecht, G., Dumont, E., Fekete, B.M., Garnier, J. and Harrison, J.A. 2010. Global river nutrient export: A scenario analysis of past and future trends. Global Biogeochemical Cycles 24, Gb0a08</ref><ref name=B15/>. Part of this emission is the gradual release of the historical phosphate enrichment of soil and sediments from human activities over more than a century<ref name=LM/>.  Because phosphorus is hardly transported by air (only as aerosol), anthropogenic P is more strongly concentrated near the land-sea interface than anthropogenic N.
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[[File:GlobalInputN.jpg|thumb|700px|center|Fig. 3. Estimated net anthropogenic nitrogen inputs (NANI) according to the world’s main river catchments. Source: Billen et al., 2013<ref>Billen, G., Garnier, J. and Lassaletta, L. 2013 The nitrogen cascade from agricultural soils to the sea: modelling nitrogen transfers at regional watershed and global scales. Phil. Trans. R. Soc. B 368:
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20130123</ref>.]]
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==Possible measures for eutrophication reduction==
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Public awareness and political priority are overarching requirements for tackling the eutrophication problem<ref name=G>Grimvall, A., Sundblad, E-L. and Sonesten, L. 2017. Mitigating marine eutrophication in the presence of strong societal driving forces. Report No. 2017:3. Swedish Institute for the Marine Environment</ref>. Eutrophication is largely related to agriculture; point sources of nutrients play a minor role and can more easily be tackled<ref name=LM/><ref name=MN/>. Dedicated fertilization strategies taking into account the N:P balance and agricultural practices such as crop rotation, drip irrigation, etc. can avoid depletion of soil nutrients<ref>IFA, 2007. IFA International Workshop on Fertilizer Best Management Practices, Brussels, Belgium, 7-9 March 2007. Imprint: Paris : International Fertilizer Industry Association, 2007</ref>. Nutrient leaching from agriculture can be reduced by recycling animal manure to cropland within watersheds. Individual behavior with regard to nutrition plays an important role; in large parts of the world, there is overconsumption of protein-rich food. Of the 120 Tg N used for crop and grass production, about 100 Tg is consumed by livestock while only 20 Tg is available for direct human consumption<ref name=S> Sutton, M.A.B., Howard, C.M., Bekunda, M., Grizzetti, B., de Vries, W., van Grinsven, H.J.M., Abrol, Y.P., Adhya, T.K., Billen, G., Davidson, E.A., Datta, A., Diaz, R., Erisman, J.W., Liu, X.J., Oenema, O., Palm, C., Raghuram, N., Reis, S., Scholz, R.W., Sims, T., Westhoek, H. and Zhang, F.S. 2013. Our Nutrient World: the Challenge to Produce More Food and Energy with Less Pollution. Centre for Ecology and Hydrology, (Edinburgh) UK, pp. 1-128 </ref>. Preservation and restoration of landscapes, especially at the land-water interfaces, promotes denitrification processes and contributes to reducing the nutrient discharge to coastal waters<ref name=MN/>. Eutrophication from mariculture can be reduced by fish farming in land-based recirculating systems along with limited use of animal feed<ref name=G/>. 
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==Related articles==
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:[[Possible consequences of eutrophication]]
 +
:[[Nutrient conversion in the marine environment]]
 +
:[[Harmful algal bloom]]
 +
:[[Algal bloom dynamics]]
 +
:[[Threats to the coastal zone]]
 +
:[[European policy on eutrophication: introduction]]
 +
 
 +
See also other articles in the [[:Category:Eutrophication]].
 +
 
 +
 
 +
==Further reading==
 +
: Our Nutrient World: the Challenge to Produce More Food and Energy with Less Pollution (2013) M.A. Sutton, A. Bleeker, C.M. Howard (eds.) https://www.pbl.nl/en/publications/our-nutrient-world-0
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==References==
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<references/>
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{{author
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|AuthorID=26102
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|AuthorFullName= Knockaert, Carolien
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|AuthorName=Carolienk}}
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{{Review
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|name=Job Dronkers|AuthorID=120|
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}}
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[[Category:Eutrophication]]

Latest revision as of 14:41, 20 September 2024

Definition of Eutrophication:
The (mostly undesired) increase in the concentration of nutrients in an ecosystem.
This is the common definition for Eutrophication, other definitions can be discussed in the article

Causes of eutrophication

Discharge of Denver sewage treatment plant in the Platte River (USA). Photo credit: Jeffrey Beall (2008)

Supply of nutrients

A major cause of eutrophication is the increased nutrient enrichment that can arise from both point and non-point sources (also called 'diffusive pollution sources'):

  • Point source pollution: Pollution that comes from contaminants that enter a waterway from a single identifiable source such as stationary locations or fixed facilities. Examples are discharges from a sewage treatment plant (Fig. 1) or industrial plants and fish farms.
  • Non-point source pollution: Pollution from widespread including human activities with no specific point of discharge or entry into receiving watercourses. Examples are leaching out of nitrogen compounds from fertilized agricultural lands (Fig. 2) and losses from atmospheric deposition.
Manure run-off, an example of non-point source pollution (Photo credit: Chris Court)

The enrichment of water by nutrients can be of a natural origin (natural eutrophication) but is often dramatically increased by human activities (cultural or anthropogenic eutrophication). Natural eutrophication has been occurring for millennia[1]. It is the process of addition, flow and accumulation of nutrients to water bodies resulting in changes to the primary production and species composition of the community. Main processes Cultural eutrophication is the process that speeds up natural eutrophication because of human activity. There are a few main sources of anthropogenic nutrient input: erosion and leaching from fertilized agricultural areas, sewage from cities and industrial waste water. Atmospheric deposition of nitrogen (from animal breeding and combustion gases) can also be important[2]. Globally, it is estimated that in 2017 more than 80 % of sewage was released into the environment without any treatment[3].

Other causes of eutrophication

An increase in the concentration of nutrients can also have other causes.

  • Reduced flushing. When flushing is reduced, the retention time of nutrients entering the water body is increased. This leads to an increase in the nutrient concentration in cases where the flushing waters are not the main nutrient suppliers. Examples are coastal lagoons in urbanized zones flushed by river runoff or by tidal action. Drought, water diversion or temporary closure of the sea inlet are possible causes of reduced flushing[4].
  • Reduced nutrient removal. Changes in environmental conditions can cause the degradation or loss of ecosystem components capable to remove nutrients. Examples are changes in salinity, turbidity or temperature detrimental to benthic fauna and flora communities, which previously promoted nutrient sequestration (e.g., peat formation) and elimination processes (e.g., denitrification). This can lead to substantial accumulation of organic matter and nutrients within the sediment, promoting anoxic, sulfide-rich conditions and high recycling of nutrients back to the water column[4].


Eutrophicating nutrients

The most common nutrients causing eutrophication are nitrogen N and phosphorus P. The main source of nitrogen pollutants is run-off from agricultural land, whereas most phosphorus pollution comes from households and industry, including phosphorus-based detergents. These nutrients enter aquatic ecosystems via the air, surface water or groundwater. Most of the commercially fixed nitrogen and mined phosphorus goes into production of fertilizer. The rising demand for fertilizer has come from the need to meet the nutritional demands of our rapidly expanding human population. The rise in intensive fertilizer use has serious implications for coastal habitats because greater application results in greater runoff, and the fraction of fertilizer lost from fields will increase with intensity of application. Increased global production of nitrogenous fertilizers have largely been linked to concerns over the relationship between water quality and eutrophication. Nutrient removal in sewage treatment plants and promotion of phosphorus-free detergents are vital to minimize the impact of nitrogen and phosphorus pollution in Europe's waters[5].


Some quantitative estimates

The emissions of N and P to the coastal ocean have doubled during the past century. More than half of these emissions are related to agriculture[6]. In 2020, the global annual production of anthropogenic reactive N (mainly ammonia, urea, nitrate) was in the order of 260 Tg N (=260 million tons N), of which 160 Tg is produced synthetically from natural gas through the so-called Haber-Bosch process (120 Tg used as fertilizer), 25-40 Tg comes from fossil fuels, 30-35 Tg from N fixation by cultivated crops and rice, 15-20 Tg from animal manure, 6-10 Tg from sewage and 2-3 Tg from mariculture[7][3][8][9][10]. About one quarter of this production finds its way (mainly through river runoff and atmospheric deposition) to the coastal ocean[7], which receives an annual load in the order of 50 Tg N/yr [11][7]. China is by far the greatest user of N fertilizer, taking 31 % of the total share. Other important users are India, USA, Europe, Brazil and Pakistan (see Fig. 3).

The annual global anthropogenic production of mineral phosphorus P in 2020 is estimated at about 20 Tg P [10], almost entirely based on mining of phosphate rock. When the use of livestock slurry and manure is included, the total phosphorus application in agriculture amounts to 25–29 Tg P per year[8]. It is estimated that 5-8.6 Tg P is flushed to the coastal ocean[12][11]. Part of this emission is the gradual release of the historical phosphate enrichment of soil and sediments from human activities over more than a century[6]. Because phosphorus is hardly transported by air (only as aerosol), anthropogenic P is more strongly concentrated near the land-sea interface than anthropogenic N.


Fig. 3. Estimated net anthropogenic nitrogen inputs (NANI) according to the world’s main river catchments. Source: Billen et al., 2013[13].


Possible measures for eutrophication reduction

Public awareness and political priority are overarching requirements for tackling the eutrophication problem[14]. Eutrophication is largely related to agriculture; point sources of nutrients play a minor role and can more easily be tackled[6][7]. Dedicated fertilization strategies taking into account the N:P balance and agricultural practices such as crop rotation, drip irrigation, etc. can avoid depletion of soil nutrients[15]. Nutrient leaching from agriculture can be reduced by recycling animal manure to cropland within watersheds. Individual behavior with regard to nutrition plays an important role; in large parts of the world, there is overconsumption of protein-rich food. Of the 120 Tg N used for crop and grass production, about 100 Tg is consumed by livestock while only 20 Tg is available for direct human consumption[16]. Preservation and restoration of landscapes, especially at the land-water interfaces, promotes denitrification processes and contributes to reducing the nutrient discharge to coastal waters[7]. Eutrophication from mariculture can be reduced by fish farming in land-based recirculating systems along with limited use of animal feed[14].


Related articles

Possible consequences of eutrophication
Nutrient conversion in the marine environment
Harmful algal bloom
Algal bloom dynamics
Threats to the coastal zone
European policy on eutrophication: introduction

See also other articles in the Category:Eutrophication.


Further reading

Our Nutrient World: the Challenge to Produce More Food and Energy with Less Pollution (2013) M.A. Sutton, A. Bleeker, C.M. Howard (eds.) https://www.pbl.nl/en/publications/our-nutrient-world-0


References

  1. ↑ De Jonge, V.N., Elliot, M. and Orive, E. 2002. Causes, historical development, effects and future challenges of a common environmental problem: eutrophication. Hydrobiologia 475-476: 1-19
  2. ↑ EEA, 2005. Source apportionment of nitrogen and phosphorus inputs into the aquatic environment. European Environment Agency Report 7, Office for Official Publications of the European Communities: Luxembourg. ISBN 92-9167-777-9. 48 pp
  3. ↑ 3.0 3.1 Tuholske, C., Halpern, B.S., Blasco, G., Villasenor, J.C., Frazier, M. and Caylor, K. 2021. Mapping global inputs and impacts from of human sewage in coastal ecosystems. PLoS ONE 16(11), e0258898
  4. ↑ 4.0 4.1 Mosley, L.M., Priestley, S., Brookes, J., Dittmann, S., Farkas, J., Farrell, M., Ferguson, A.J., Gibbs, M., Hipsey, M., Huang, J., Lam-Gordillo, O., Simpson, S.L., Tyler, J.J., Waycott, M. and Welsh, D.T. 2023. Extreme eutrophication and salinisation in the Coorong estuarine-lagoon ecosystem of Australia's largest river basin (Murray-Darling). Marine Pollution Bulletin 188, 114648
  5. ↑ EC, 2002. Eutrophication and health. European Commission, Office for Official Publications of the European Communities: Luxembourg. ISBN 92-894-4413-4. 28 pp
  6. ↑ 6.0 6.1 6.2 Le Moal, M., Gascuel-Odoux, C., Menesguen, A., Souchon, Y., Etrillard, C., Levain, A., Moatar, F., Pannard, A., Souchu, P., Lefebvre, A. and Pinay, G. 2019. Eutrophication: A new wine in an old bottle? Science of the Total Environment 651: 1-11
  7. ↑ 7.0 7.1 7.2 7.3 7.4 Malone, T.C. and Newton, A. 2020. The Globalization of Cultural Eutrophication in the Coastal Ocean: Causes and Consequences. Front. Mar. Sci. 7:670 Cite error: Invalid <ref> tag; name "MN" defined multiple times with different content
  8. ↑ 8.0 8.1 Penuelas, J., Poulter, B., Sardans, J., Ciais, P., van der Velde, M., Bopp, L., et al. 2013. Human-induced nitrogen–phosphorus imbalances alter natural and managed ecosystems across the globe. Nat. Commun. 4: 2934
  9. ↑ Lu, C. and Tian, H. 2017. Global nitrogen and phosphorus fertilizer use for agriculture production in the past half century: shifted hot spots and nutrient imbalance. Earth Syst. Sci. Data 9, 181–192
  10. ↑ 10.0 10.1 FAO. 2019. World fertilizer trends and outlook to 2022. Rome
  11. ↑ 11.0 11.1 Beusen, A. H. W., Bouwman, A. F., Van Beek, L. P. H., Mogollón, J. M. and Middelburg, J.J. 2015. Global riverine N and P transport to ocean increased during the twentieth century despite increased retention along the aquatic continuum. Biogeosciences Discuss. 12: 20123–20148
  12. ↑ Seitzinger, S.P., Mayorga, E., Bouwman, A.F., Kroeze, C., Beusen, A.H.W., Billen, G., Van Drecht, G., Dumont, E., Fekete, B.M., Garnier, J. and Harrison, J.A. 2010. Global river nutrient export: A scenario analysis of past and future trends. Global Biogeochemical Cycles 24, Gb0a08
  13. ↑ Billen, G., Garnier, J. and Lassaletta, L. 2013 The nitrogen cascade from agricultural soils to the sea: modelling nitrogen transfers at regional watershed and global scales. Phil. Trans. R. Soc. B 368: 20130123
  14. ↑ 14.0 14.1 Grimvall, A., Sundblad, E-L. and Sonesten, L. 2017. Mitigating marine eutrophication in the presence of strong societal driving forces. Report No. 2017:3. Swedish Institute for the Marine Environment
  15. ↑ IFA, 2007. IFA International Workshop on Fertilizer Best Management Practices, Brussels, Belgium, 7-9 March 2007. Imprint: Paris : International Fertilizer Industry Association, 2007
  16. ↑ Sutton, M.A.B., Howard, C.M., Bekunda, M., Grizzetti, B., de Vries, W., van Grinsven, H.J.M., Abrol, Y.P., Adhya, T.K., Billen, G., Davidson, E.A., Datta, A., Diaz, R., Erisman, J.W., Liu, X.J., Oenema, O., Palm, C., Raghuram, N., Reis, S., Scholz, R.W., Sims, T., Westhoek, H. and Zhang, F.S. 2013. Our Nutrient World: the Challenge to Produce More Food and Energy with Less Pollution. Centre for Ecology and Hydrology, (Edinburgh) UK, pp. 1-128


The main author of this article is Knockaert, Carolien
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Citation: Knockaert, Carolien (2024): What causes eutrophication?. Available from http://www.coastalwiki.org/wiki/What_causes_eutrophication%3F [accessed on 10-11-2024]



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