1 / 26

Eutrophication 1 Definition and History

Eutrophication 1 Definition and History. Alice Newton University of Algarve. Research Projects. LOICZ (Land-Ocean Interaction in the Coastal Zone) IMBER (Integrated Marine Biochemistry and Ecosystem Research) GEOHAB (Global Ecology and Oceanography of Harmful Algal Blooms)

leia
Download Presentation

Eutrophication 1 Definition and History

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Eutrophication 1Definition and History Alice Newton University of Algarve

  2. Research Projects • LOICZ (Land-Ocean Interaction in the Coastal Zone) • IMBER (Integrated Marine Biochemistry and Ecosystem Research) • GEOHAB (Global Ecology and Oceanography of Harmful Algal Blooms) • National Estuarine Assessment, NOAA (USA) • EU projects http://europa.eu.int/comm/research/eloise/eloise-p.html • NationalINAG/IMAR: Identification of Sensitive Areas and Vulnerable Zones in Four Portuguese Estuarieswww.inag.ptwww.imar.pt • RegionalMARE (Marine Research on Eutrophication) Programme (funded by the Swedish Foundation for Strategic Research) http://www.mare.su.se • EuropeanOAERREhttp://tejo.dcea.fct.unl.pt/oaerre/http://www.oaerre.napier.ac.uk/

  3. Links • Agriculture • Fertilizer use • Domestic Animal Wastes Tourism • Atmospheric pollution • Photochemical smog • Acid Rain • Greenhouse effect Fisheries Water quality impairment Biogeochemical cycles Eutrophication Aquaculture Oxygen BOD Hypoxia Biodiversity Macrophytes Phytoplankton HAB

  4. Links to Other Topics • Agriculture http://www.fertilizer.org/ifa/ http://www.tfi.org/ Fertilizer use Input of N & P > outputs from crops • Domestic Animal Wastes manure production>>use XS N &P reaches aquatic ecosystemXS N also volatilized • Water quality impairment • Atmospheric pollution • Photochemical smog (Nitric Oxide, NO) • Acid Rain (Nitric Acid) • Greenhouse effect (Nitrous Oxide, N2O) • Soil and Erosion • Nitrates leach Ca, Mg & K from soil • Biodiversity

  5. Biogeochemical cycles:N, P and C. Redfield ratio. Si Oxygenin the marine environment, Primary Production, Respiration, BOD, Hypoxia http://192.168.1.102/hypox5.pdf Phytoplankton and harmful algal blooms (HAB) ioc.unesco.org/hab/

  6. Defining Eutrophication

  7. Some etymology… • Eu: Greek prefix “good” and “well” • Troph: Greek “nourishment” “nutrition” “feeding” • Eutrophic: Positive connotation • Eutrophication: Negative connotation

  8. Definition • Eutrophication: nutrient enrichment of natural waters • Naturaleutrophication in regions of upwelling: cold, deep, nutrient-rich waters rise to surface eg Chile • Anthropogeniceutrophication is result of nutrient pollution of natural waters eg lakes, rivers, aquifers, estuaries, bays, coastal waters

  9. Scientific definition of Eutrophication…the good? • “Stimulation of algal growth by enrichment of the aquatic environment with mineral nutrients” (Richardson, 1989) • Natural processes are the agents of enrichment: includes naturally eutrophic coastal waters, such as upwelling regions

  10. Courtesy of Gay Mitchelson–Jacob Variation in the Productivity of the Oceans Primary Productivity using global monthly SeaWiFS data of chlorophyll (Nov 77-Oct 99) and the vertically generalised production model from Behrenfeld & Falkowski (1977)

  11. Atlantic is much nutrient-rich and more productive than the Mediterranean Mediterranean Chlorophyll CZCS composite Courtesy of Gay Mitchelson–Jacob

  12. Upwelling regions are especially productive such as the coast of Chile SeaWiFS Chlorophyll, 18 Jan 2000 ChileCourtesy of Gay Mitchelson–Jacob

  13. Coastal Upwelling off W. Africa Coastal Upwelling Chlorophyll Concentrations (CZCS), Cape Verde IslandsCourtesy of Gay Mitchelson–Jacob

  14. Management definition of Eutrophication… the Bad? • Anthropogenic Eutrophication: mankind is the agent responsible for nutrient enrichment • European Environment Agency definition: “Enhanced primary production due to excess supply of nutrients from human activities, independent of the natural productivity level for the area in question”

  15. UK EA definition “The enrichment of waters by inorganic plant nutrientswhich results in the stimulation of an array of symptomaticchanges. These include the increased production of algaeand/or other aquatic plants, affecting the quality of thewater and disturbing the balance of organisms presentwithin it. Such changes may be undesirable and interferewith water uses.”

  16. Nutrients & Eutrophication, EEA • The main nutrients causing eutrophication are N in the form of nitrate,nitrite or ammonium and Pin the form of ortho-phosphate. • In addition,supply of bioavailable organicP and N cause eutrophication • Silicate is essential for diatom growth, but it is assumed thatsilicate input is not significantly influenced by human activity. • Enhancedprimary productivity may exhaust silicate and change the phytoplanktoncommunity from diatoms to flagellates.

  17. Eutrophication process UK EA

  18. Early Eutrophication Model Responses: Changes in Chlorophyll Primary Production System Metabolism Oxygen Nutrient loading Early conceptual models focused on directresponses of coastal waters, such as stimulation of phytoplankton blooms.

  19. Contemporary conceptual model Indirect Responses Benthic biomass Pelagic biomass Vascular plants Habitat diversity Water transparency O C in sediments Sediment biogeochemistry Bottom-water oxygen Seasonal cycles Mortality Biodiversity Direct Responses Chlorophyll Primary Production Macroalgal biomass Sedimentation of O C System Metabolism Phyto. community Si:N N:P Oxygen HAB Filter Nutrient loading Cloern J.E. 2001

  20. Contemporary conceptual model • Growing awareness of the complexity of theproblem • Attributes of specific bodies of water createenormous variations in their responses • Cascade ofdirect and indirect effects • Appropriate management actions to reduce nutrient inputs canreverse some of the degradationcaused byenrichment.

  21. History of Eutrophication

  22. History of Fertilizer Historical fertilizer shortage • 18th Century England “mined” battlefields and catacombs • 19th Century USA used bones from buffalo killing fields • Guano deposits mined eg Navassa guano trench

  23. Haber-Bosch Process • Fritz Haber(Nobel prize winner) described chemical process to produce NH3 from N2 & CH4 • Carl Bosch(Nobel prize winner) perfected commercial manufacture

  24. Industrial N fixation • N2 from atmosphere mixed with CH4 and heated under pressure with a metallic catalizer produces CO2 and NH3 (82%N) • Mean plant production is 1.5 million kg ammonia per day

  25. History of Eutrophication • Eutrophication first noticed in lakes where P is the main problem • Also noticed in rivers • Estuaries: eg Chesapeake bay • Bays and coastal waters affected: eg Gulf of Mexico • 70 % of world population lives in coastal plains, increasing pressure

More Related