Study Finds Organic
Agriculture Builds Healthy Soil and Uses 50% Less Energy than Conventional
Organic agriculture is finally making its presence felt in the worldwide scientific community. A study published in the May 31, 2002 issue of the journal Science, the first article on organic agriculture that the journal has ever published, finds that organic agriculture builds healthy soil and uses 50% less energy than conventional farming. For the past 24 years the Swiss DOK trial, an acronym derived from the German designations biologisch-dynamisch, organisch-biologisch and konventionell, has compared conventional agricultural practice with organic and biodynamic agriculture. Nowhere in the world has such a long-term study been conducted.
The DOK trial demonstrates that organic crop production is amazingly efficient. Although expenditure on fertilizers and energy was 50% lower and pesticide use was 97% lower, yields of organic crops over a 21-year period were only 20% lower on average.
The DOK trial is also informative on the issue of soil fertility, which is clearly encouraged by organic husbandry. Double the numbers of soil microorganisms, earthworms and ground beetles are found in the study's organic plots. Organic production systems rely in part on organic soil activity to achieve considerable yields using lower inputs of non-renewable resources while maintaining higher soil fertility and better soil structure.
The organic plots not only exhibited higher soil-organism activity, but also a greater diversity of microorganism, weed and ground beetle species. Hence organic farming helps to maintain high levels of biodiversity despite agricultural use of the land. The active, diverse communities of microorganisms ensured efficient use of organic sources of carbon in the soil. It is particularly interesting that the evidence points to a definite correlation between efficient above-ground production (energy input per unit of yield) and efficient production in the soil (soil respiration per unit of microbial biomass). When subjected to intensive interventions via fertilizers and pesticides, the microorganisms evidently become stressed and make heavier demands on resources for their own survival.
The DOK trial is being conducted in Switzerland by the Research Institute of Organic Agriculture (FiBL) in Frick and the Swiss Federal Research Station for Agroecology and Agriculture (FAL) in Zürich-Reckenholz. It will be continued for at least the next four years.