Growth and reproduction of Stipa Krylovii population on a grazing gradient
牧压梯度对克氏针茅生长和繁殖的影响

The growth and reproduction of Stipa krylovii on a grazing gradient,that is,no grazing(NG),light grazing(LG),moderate grazing(MG),and heavy grazing(HG),were studied in 1995 on a tylical steppe dominated by Stipa krylovii .This research was carried out on a series of comparative sampling plots along with a spatial gradient of grazing.The results showed that over grazing for years was always associated with tussock fragmentation,size miniatwing,the process of tillering nodes going up near to the soil surface and declining of carbohydrate reserves(soluble,sugar,reducing sugar,fructose,and sucrose)in the stem base and roots.On the contrary moderate grazing was always led to a rational self control on the size,the ratio of vegetative and reproductive tillers.