Book of Abstracts
11th IFOAM Scientific Conference
11-15 August 1996, Copenhagen, Denmark
Agricultural Research Centre, Research Station for Ecological Agriculture, FIN-51900 Juva.
By following the farm gate balance between nutrients coming in from outside the farms and those going out with agricultural products it is possible to evaluate the ecological efficiency of the activities and in the long term the nutrient pollution caused by the agriculture. However, some problems are faced if the farm gate balance is only measure to evaluate the ecological efficiency, e.g. how to compare crop farms to livestock farms, what is the role of production intensity or farming system. Thus, the farm gate balance is needed to be disaggregated into components. In this study the farm gate balance (E = output:input) is disaggregated into four components: crop (C), livestock (L), intensity (I) and farming system (F) factor. E = f(C,L,I,F), 0 (C,L,I,F) 1.
Absolute and relative values of factors are discussed: what are the minimum nutrient losses in theory and in practise, i.e. when the value of particular factor is 1 (100 %). To determine the factors above long term detailed data on farm level is used from book keeping farms in Finland from 1965 to 1990.
Output/input rate for nitrogen, phosphorus and potassium was worse than 1/3 in Finland in the end of 1980's. Poor nutrient balance at present agriculture is resulted from all factors mentioned, but high intensity of fertilization seems to be the major factor. Relatively high prices of products compared to prices of inputs (fertilizers) have encouraged to increase intensity.
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