Effects of cattle and sheep grazing on the community stability of grass/Trifolium repens grasslands Yungui Area

Grass/Trifolium repens grassland is one of the main grazing and mowing pastures in the karst areas of southern China. To clarify the influence of vegetation composition and community stability of grass/T. repens grasslands grazed by different livestock grazing, which will reveal its vegetation succession characteristics to a certain extent. The plant community characteristics, species diversity, biomass composition and community stability of grass/T. repens grasslands under cattle and sheep grazing were quantitatively analyzed in this study. The results showed that: 1) the biomass of dead matter and the number of plant species on the grasslands were GC > GS, while the species Simpson index was GS > GC. 2) the aboveground biomass components of the lawn grasses (Lolium perenne, Dactylis glomerata and native grasses), native dicotyledon (Verbenaceae, Plantaginaceae, Oxalidaceae and Cruciferae) and medium palatability herbages were GC > GS; while the seeding white clover composition was GS > GC. In addition, the aboveground biomass dominated by grasses (77.20%) for GC and by grasses (51.79%) and leguminous (28.02%) for GS. 3) the content of K in the grassland soil was GC > GS. 4) the species Raunkiaer frquency histogram of GC was inversely J-type, and community succession value was GS (45.45)> GC (37.08). The research shows that the community of GC is relatively stable, while GS is in a higher stages of succession, and for the maintaining of community stability and species diversity of grass/T. repens grasslands, cattle’s grazing is more benefited than the sheep. Therefore, mixed grazing or rotation grazing of cattle and sheep can be implemented to improve the stability and productivity of grass/white clover grasslands.