ECW Novotny

Diffuse Pollution from Agriculture in the World (II): 

Diffuse Pollution from Agriculture in the World (II) Vladimir Novotny Northeastern University Boston, MA, USA novotny@coe.neu.edu Presentation at the European Commission Workshop “Where do the fertilizers go? Joint Research Centre Ispra, Italy June 28-29, 2005

Slide2: 

IWA Diffuse Pollution Group Conference “ Agriculture and Environment” in Venice 1984 (Giorgini and Zingales Workshop on Agricultural Diffuse Pollution in Teolo (Veneto) 1997 (Bendoricchio, 1999) IWA Leading Edge Conference on Managing Rural Diffuse Pollution, Edinburgh – April 2006 (Contact Brian D’Arçy, SEPA)

Lagoon of Venice Problems: 

Lagoon of Venice Problems Drainage of wetlands Intensive agriculture industrial fertilizers and pesticides Urbanization and transportation Tide barrier ?

Problems of the Baltic Sea: 

Problems of the Baltic Sea Nutrients (N and P) Eutrophication Excessive algae growth Oxygen depletion

Problems of the Baltic Sea- Algae bloomsBlue-greensOxygen depletion: 

Problems of the Baltic Sea - Algae blooms Blue-greens Oxygen depletion Source: Claus Hagebro Professional Secretary, M.Sc. Helsinki Commission

Other areas of large scale problems: 

Other areas of large scale problems Chesapeake Bay Susquehanna River Gulf of Mexico Mississippi River Black Sea Danube River North Sea Elbe

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AGRICULTURAL LAND % Willamette River Basin, OR Remaining land use is mostly forest Source USGS

Problems : 

Problems Eutrophication Dissolved oxygen, turbidity Algal toxins, taste and odor Increased cost of treatment Impairment of swimming (aesthetic, rash, gastrointestinal diseases) Disappearance of sea grasses Loss of diversity Fish, shell fish and marine mammals kills, aquatic life impairment

Important Periods of Change of Agriculture: 

Important Periods of Change of Agriculture 1990 1950 1850 800 Subsistence Farming Feudal Farming Green Revolution Organic Farming Soil conservation BMPs 1940 Land conversion Industrial fertilizers and pesticides

Root Causes of Diffuse Pollution: 

Root Causes of Diffuse Pollution Population Growth and Increased Standard of Living Need for food can be satisfied by Converting more land to agriculture Intensification of agriculture

Green Revolution(Intensive Agriculture): 

Green Revolution (Intensive Agriculture) New crop cultivation methods Developing new cop varieties Irrigation Dramatically increased chemical fertilizer and pesticide applications Mechanization N.E. Borland

Green revolution : 

Green revolution Has dramatically increased crop yields More land would have to be converted to agriculture without green revolution It brought increased standard of living Made traditional family farms economically unsustainable Diffuse pollution dramatically got worse Farm subsidies encourage large intensive operations

Worldwide increases in fertilizer use: 

Worldwide increases in fertilizer use Source : Ongley

Pollution from animal operations: 

Pollution from animal operations Change of animal operations from small scale family animal husbandry and pasture to concentrated feedlots made possible by green revolution with hundreds (cattle) or thousands (pigs, chickens, turkeys) animals in a small space Consequences: Large increase of diffuse pollution on top of the nutrient losses from fields Poor disposal into soils Soil overloading, disposal on frozen soils

Pollution from land use changes: 

Pollution from land use changes Deforestation to subsistence farming Wetland drainage Irrigation of dry lands and irrigation return flow Cultivation of prairies Conversion of range land and pasture Conversion to aquiculture in tropical countries and elimination of mangrove wetlands

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Borlaug estimated that if green revolution had not occurred then additional 1.8 billion hectares would have been needed to satisfy the current needs of population This “new” agricultural land would come from converted rain forest (tropical humid countries) or from marginal more erosive lands (China)

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Nutrient Balance on a World Basis and for the European Community World European Community N P N P Addition of Nutrients (106 tonnes) Fertilizer 70 14.4 9.3 2.0 Waste products 58 12 7.1 1.4 Atmosphere 89 - 1.3 - Total (Kg/ha) 13 5.6 96 26.8 Extraction of Nutrients (106 tonnes) Crop production 60 12 10 1.9 Denitrification 157 - 4.3 - Total (Kg/ha) 13 2.5 78 15 Net addition (Kg/ha) 0 +3.1 +18 +1.8

Accumulation in soils and aquatic systems: 

Accumulation in soils and aquatic systems 20% of applied phosphorus and 50% of applied nitrogen to land reach receiving waters (NAWQA) Accumulation rate of phosphorus ranges 3 to 18 kg ha-1 year-1 Highest accumulations of nutrients from fertilizers and waste application Japan EC Community US Fertilizer use on suburban lawns in the US is several times larger (per unit area) than that ob farms

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Nutrient balance and content of Vltava River in Czech Republic (Slapy Reservoir)

IMPACT OF AGRICULTURE: 

IMPACT OF AGRICULTURE Intensive agriculture in the “Bread/Corn basket of America” High nutrient loads to the river and the Gulf of Mexico Nitrogen is the limiting factor for the eutrophication problems in the Gulf of Mexico Gulf of Mexico

Extent of Hypoxia in the Gulf: 

Extent of Hypoxia in the Gulf Frequency of Occurrence 1985 - 1999 Rabalais, et al. 22 400 km Distance Paris to London = 490 km

Area of hypoxic zone 1985 - 2002: 

Area of hypoxic zone 1985 - 2002 Source Rabalais et al. By interpolation, hypoxia problems started around 1960

Overall balance of nitrogen: 

Overall balance of nitrogen

Phases of hypoxia: 

Phases of hypoxia Conversion of prairies and subsistence farming - late 1800 -1950 steady state – period of resilience Introduction of commercial fertilizers after 1950 upset the steady. Hypoxia might have started around 1960 but was not observed until 1985 – period of vulnerability Hypoxia appeared after 1980 with concurrent diminishing of shellfish population – period of impairment

Subglobal transport of nitrogen: 

Subglobal transport of nitrogen Source: National Research Council

Period of Recovery?: 

Period of Recovery? Subsequent presentation

Diffuse pollution is related to or a consequence of the use or misuse of land Agricultural Diffuse Pollution is caused mostly by misuse and overuse of land : 

Diffuse pollution is related to or a consequence of the use or misuse of land Agricultural Diffuse Pollution is caused mostly by misuse and overuse of land

Community response: 

Community response Intensive research and development of BMPs Soil conservation (since mid 1930s) Integrated pest management Buffer strips and field borders Animal feedlot management Targeting fertilizer needs of crops Incorporation and restoration of wetlands Grass root movement to organic farming Taking polluting agricultural lands out of production

Three types of farming: 

Three types of farming Subsistence (mostly small family farms) Expanded by land conversion Without education and some incentives hardly environmentally sustainable (slash, burn, farm and move away) Subsistence farmers in developing countries often may not reason beyond providing food for their families Commercial (Large industrial farms and animal operations) High reliance on fertilizers and pesticides, mostly monocultural Large increase of nutrient inputs into receiving waters

Organic Farming: 

Organic Farming Ecologically manageable systems Still relatively small Dramatic growth in Europe and US Is it sustainable and/or less polluting? Converting the entire agriculture sector to organic farming is a challenge and only a long term goal

Sustainable Agriculture?: 

Sustainable Agriculture? Shortest definition of sustainability: A sustainable agriculture is one that, over a long term, (1) enhances environmental quality and the resource base on which agriculture depends, (2) provides for basic human food and fiber needs, (3) is economically viable, and (4) enhances the quality of life for farmers and the society as whole American Society of Agronomy Dream, Conflicting or Achievable?

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Three Types of Farming Parameter Subsistence Commercial Sustainable (organic) Social identity Family Corporation Family or Community Nature of change Uncontrolled Controlled Planned and anticipated Government support Education and Subsidies for Same as subsistence grants for BMPs production and set- aside land Relation to environment Vulnerable Control over Anticipatory Natural resources Finite; consume; Develop and Finite; conserve and relocate when and consume preserve exhausted Role of government Undeveloped and Coordination, Regulate unstable protect rights and needs of land owners Knowledge base Tradition Science and Science and technology technology Impact on diffuse pollution Localized, could be Significant and Small, often none significant over widespread long term Cost of externalities Medium Large None From Novotny (2003) and Padgitt and Petrzelka (1994)

Conclusions: 

Conclusions Over the last 50 years there has been a dramatic shif from subsistence family farming to commercial large scale farms and feedlots with a consequence of large losses of fertilizers into receiving waters (diffuse pollution) More environmentally sustainable farming is emerging Ecologically sustainable (minimum diffuse pollution) farming may emerge by a conversion of large farm operations to more sustainable farming. This can only be achieved by regulation and rethinking or eliminating subsidies

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In memoriam Professor Giuseppe Bendoricchio 1950-2003 Founder of the IWA Diffuse Pollution Group