Floods and Other Possible Adverse Environmental Effects of Meadowland Area Decline in Former West Germany

6   ha, or 6% of the country's total area. The environmental implications of this large-scale conversion have so far received little attention; the present study examined some of these implications. A review of research on soil physical and chemical aspects of the conversion of permanent grassland into arable land reveals that such a large-scale conversion may have considerable effects upon the environment. For example, due to the mineralization of soil organic matter a release of NO₃ and CO₂ into the environment can be expected on the order of 10 t N and 100 t C per hectare. Environmentally equally severe, if not worse, is the increased amount of surface runoff that can be expected from converted grassland soils in arable land during winter because of surface sealing and soil compaction. This increased surface runoff, in combination with the runoff from other farmland, may be one of the reasons for the growing frequency of floods along major German rivers in recent years. In view of the lasting adverse environmental effects of permanent grassland conversion and the subsidized agricultural surpluses in Germany today, we conclude that a reconversion of arable land into permanent grassland may be beneficial both environmentally and economically.