Preliminary research on environmental impact of woodland grazing by pigs

6 castrate pigs about 30 kg live weight each entered in a fence into hilly woodland area. The pigs were bred until about 140 kg live weight. After 10 months of pasture breeding, the environmental damages (cover ground, plants and soil characteristics) by rooting and trampling were evaluated. The damages to cover ground and to shrubs and to physical structure (Fissures and Aggregate stability) caused hydro-geological instability with soil erosion and landslides. Removing surface layers of soil caused considerable loss of organic matter (Total Organic Carbon and Total Nitrogen), microbial activity (Microbial ATP and breathing) and enzyme activity changes (Total β−glucosidase and Extra cellular β−glucosidase). Damages to native plants are different in relation to the root and the trunk kinds, and to the palatability of leaves and apexes which result inversely related whit the abundance of disagreeable substances content (ADL, Tannins, Resins, Latex).