The investigation was carried out on an farm in south Bohemia. The area in question comprises approximately four hectares and has been used since 1995 for the over-wintering of about 90 cows from October till the beginning of May. According to Schloter, At the end of this season, we could clearly see the consequences of the over-wintering, on the soil. Unlike typical summer grazing, where the animals spread out evenly, the animals on the winter pastures prefer to stay near the feed house. As a result, no vegetation was visible any more in this area, and the ground was strongly compressed. In addition, this area was marked by a very high incidence of organic matter from the excrement of the animals. In more distant areas, the consequences were far less drastic.
The intensive grazing in the areas close to the cowshed led to a clear increase of methane emissions throughout the whole winter. These showed 1,000 times more than the control areas, where no bovine animals were kept. Methane oxidation is the metabolic way that can lead to the breaking down of the methane. Interestingly, the classical process of methane oxidation, which is related to aerobic conditions, was restrained in the intensely grazed areas. According to Schloter, this is explained by the high quantities of urea in the ground. The scientists were able to show further that methane producing micro-organisms from the gastro-intestinal tract of the cattle could survive in the soil and suppress parts of the autotchtone microflora. The newcomers profited from the environmental conditions in these soil, namely the extensive organic material.
Although in summer and autumn the animal
|Contact: Heinz Joerg Haury|
GSF - National Research Center for Environment and Health