EFFECTS OF INTENSIVE CATTLE TRAMPLING ON SOIL PLANT EARTHWORMS SYSTEM IN 2 GRASSLAND TYPES

An experimental study of the consequences of intensive cattle trampling was carried out pure white clover and on a perennial rye-grass-white clover association. Direct and indirect effects of trampling on earthworm and plant communities and on soil structure were found. Trampling led to destruction of a large portion of the aerial system, stolons and roots, with removal of some of the vegetation cover (soil at least 50% bare). From a general view, trampling in experimental plots induced a large decrease (from 70 to 86%) of earthworm density and biomass. The functional structure was modified for the benefit of large size species. Small size species were more sensitive: some species, such as Lumbricus castaneus and Allolobophora chlorotica chlorotica typica disappeared. An increase of the proportion of adults could be related to larger sensitiveness of juvenile individuals in the same population and explained a significant increase of the individual mean weight. Different responses existed in function of the grassland type related to depth.