getting farming right : reflections on ecological sustainability
TRANSCRIPT
Getting farming rightreflections on ecological sustainability
(nitrogen in the landscape)
November 12, 2016
Cary Institute of Ecosystem Studies
Joshua Ginsberg, President
Why do we care about Nitrogen?
“In most estuaries, over-enrichment of N leads to eutrophication, presently the greatest pollution problem in coastal marine waters of the United States “
• Increased acidity of soils, water
• Human health (ozone, particulates)
• Forest health (ozone, acidity)
• Ground (drinking) water contamination
(Driscoll et al. 2001)
1. Lightning Strikes
2. Fixation by microorganisms
3. Atmospheric
deposition
4. Uptake
5. Watershed runoff
6. Denitrification by
bacteria.
Nitrogen Fluxes:
Nitrogen Sources:
(Driscoll et al. 2001)
1. Imported food/feed
2. Vehicle emissions
3. Power plantemissions
4. Fertilizer imports
5. Fixation in croplands
6. AgriculturalEmissions
7. Atmospheric deposition
8. Sewage
9. Agricultural Runoff
10. Urban runoff
11. Riverine discharge
Nitrogen Fluxes:
Nitrogen Sources:
Eutrophication in US Estuaries
(Bricker et al. 1999)
2/3 of Estuaries impaired • 40% high • 25% moderate • 35% low
Animal waste (manure) and human waste (sewage) are not considered as new inputs, as they represent recycling within a region
Nitrogen in, nitrogen outinto coastal waters where the problems amplify
Boyer et al. 2002 Biogeochemistry
Boyer et al. 2002 Biogeochemistry
Food for people, feed for animals can exceed direct fertilizer use as source of N2
Juvenile mussels were rare or absent when ammonia was high
Strayer & Malcom, Ecol. Appl., 2012
Ammonia predicted mussel recruitment
What can be done about Nitrogen?
Engineering nutrient “sinks” Riparian zones
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Engineering nutrient “sinks” Artificial drainage
Ontario Ministry of Agriculture, Food, and Rural Affairs
Engineering nutrient “sinks” Wetlands
Mitsch WJ, Gosselink JG.. 2000. Wetlands, 3rd ed. New York: John Wiley & Sons
How do we pay for this?
• Long term investment in our land
• 2012 Farm Bill (to be reauthorized in 2019)
– Food stamps ($750 billion)
– Crop subsidies/crop insurance ($140 billion)
– Environmental programs ($55 billion)
Environmental Programs … detail• Agricultural Management Assistance Program (AMA)
• Chesapeake Bay Watershed Initiative (CBWI)
• Cooperative Conservation Partnership Initiative (CCPI)
• Conservation of Private Grazing Land Program
• Conservation Reserve Program (Farm Service Agency)
• Conservation Stewardship Program (CSP)
• Environmental Quality Incentives Program (EQIP)
• Agricultural Water Enhancement Program (AWEP)
• Conservation Innovation Grants (CIG)
• Farm and Ranch Lands Protection Program (FRPP)
• Grassland Reserve Program (GRP)
• Healthy Forest Reserve Program (HFRP)
• Small Watershed Rehabilitation Program
• Wetlands Reserve Program (WRP)
• Wildlife Habitat Incentive Program (WHIP)
Can organic agriculture feed the world? Catherine Badgley and Ivette Perfecto
Renewable Agriculture and Food Systems: 22: 80–85
• Maybe
• Organic methods provide enough calories to support thewhole human population eating as it does today
• Nitrogen-fixing legumes (green manures) can replacesynthetic nitrogen fertilizer currently in use
• Gap is small, a developed world problem (poor farmers use fewer fertilizers)
Questions?
With thanks to:
– Peter Groffman
– Dave Strayer
– Stuart Findlay
– Lori Quillen