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Nutrient cycles and flows in agroecosystems. What is missing?. Dissipation into the surrounding environment. *. *. Key terms. Fertilizer raw materials. Cycles Flows Stocks. Soil nutrient reserves. Total N inputs to IL soils. (alfalfa and other forage legumes).
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Nutrient cycles and flows in agroecosystems What is missing? Dissipation into the surrounding environment
Key terms Fertilizer raw materials Cycles Flows Stocks Soil nutrient reserves
Total N inputs to IL soils (alfalfa and other forage legumes) Mg = 1 x 106 g = 1000 kg = 1 metric ton
N inputs vs. river export Net input = Gross inputs - outputs 1993
Mining Prairie N Anthropogenic N inputs
Approximately 40% of IL fields have artificial drainage
Yield maps have made drainage problems much more obvious
Redistribution of nutrients excess
Mid-Atlantic Manure P and N Surplus State P N --Million Lbs in Excess-- DE 7.3 14.6 MD 10.4 19.6 NJ 0.9 1.8 NY 3.3 4.2 PA 23.7 33.8 VA 24.8 42.3 (Source: USDA, 2001)
Nutrient depletion in Africa http://www.fao.org/docrep/006/y5066e/y5066e02.jpg
Nutrient budgets on organic farms a review of published data N Most organic farms in developed countries do not have nutrient deficits even though they don’t use conventional fertilizers. P K http://www.organic.aber.ac.uk/library/Nutrient%20budgets%20on%20organic%20farms.pdf
Daily inputs and outputs of dry matter, P and N http://edis.ifas.ufl.edu/DS096
N 20% maintenance P 13% maintenance K 12% maintenance 20% 27% 13% 60% 60% 75% urine feces N 50% 50% P 10% 90% K 90% 10% http://extension.oregonstate.edu/catalog/html/em/em8586/
Nitrogen budget for a dairy in Florida (lbs of N/acre) http://edis.ifas.ufl.edu/DS096
Nitrogen budget for 4 dairies in New York http://www.dairyn.cornell.edu/pages/10concerns/15nutrient.shtml
Annual manure production and nutrient value for 100 cows ~ 2 X in 2008 Table 3.