Impact of grazing on soil biota in a Mediterranean grassland

The effect of cattle grazing on the soil nematode and protozoan communities, and on microbial biomass, was measured in Israel's northern highlands. Three grazing areas were compared: (1) with 1.1 cow ha(-1) y(-1); (2) 0.55 cow ha(-1) y(-1); and (3) control-no grazing for almost 18 years. Soil samples were collected from the upper 10 cm level of each area (n = 24), in autumn, before the onset of the rainy season, in order to analyse soil moisture, organic matter, total nitrogen, microbial biomass, soil respiration, soil free-living nematodes, as well as ciliate and flagellate populations. Soil microbial biomass and soil free-living nematodes showed no clear differences in impact between heavy and moderate grazing. However, ciliates and flagellates showed a significant response to different grazing pressures. Copyright (c) 2005 John Wiley & Sons, Ltd.