ifoam'96 ifoam'96
Book of Abstracts
11th IFOAM Scientific Conference
11-15 August 1996, Copenhagen, Denmark
EcoWeb Denmark


Measuring the Biological Efficiency of Mixed Farms. P3; 45

Lieblein, G.1 &. Breian, J. A.2

Ecological Agriculture Program, Agricultural University of Norway, P. O. Box 5022, 1432 Ås, Norway

It critically important to complement existing economical models for measuring the performance of whole farming systems. Such models should focus on biological properties, require a minimum of recordings and be inexpensive in use. They should be flexible enough for use by farmers, to enable them to »take the biological pulse of the farm«.
Basic questions in the tool development process are: What is the net production of the farm as a whole? How much of the net production is based on the farms own resources? When import of mineral N fertilizer decreases and ceases as a result of the transition conventional to ecological farming practises, can net yields of the farm as a whole be maintained or increased?
The model that we presently are developing requires the following recordings at farm level: 1. Livestock and plant products for sale. 2. Calculation of net yields of fodder. Net yield is the yield that, according to feeding standards, supports a certain output of animal produce. 3. Mapping of part of net yield stemming from outfield pastures and imports, as well as changes in number/weight of animals (change of status). All recordings are converted to energy units (MJ).
Since we consider the farm basically to be a human activity system, it is necessary to interact with farmers in the model development process. If the aim is to develop a tool that can aid farmers in their desicion making, then farmers must participate in the process of developing those tools.Therefore case farms have been included in the work, farms that alreadyhave or presently are converting from conventional to ecological farming practices. In a continuous process, results of the work as well as the tools themselves are presented to the farmers on the case farms, for feedback and suggestions for improvement.