关键词: 践踏, 践踏单位, 践踏当量, 践踏强度, 试验践踏, 模型

Abstract: Trampling is one of the three impact activities(trampling,defoliation,and excretion)performed by a grazing animal on grassland and also the major reason for range degradation.Little is known about the result of trampling-induced feedback among the soil environment,grass,and their interrelationship.In addition, more information is needed about the effects of animal trampling on the managed grazing ecosystems.In typical steppe of loess plateau regions,where the management objective is to maintain the grassland ecosystem structure and function,the impacts of grazing trampling could be a serious problem.The object of the study was to separately evaluate the effect of trampling on the typical steppe in Huanxian County,eastern Gansu Province,China.A series of field experiments were conducted for two years including the tailing-up observation of trampling intensity of Tan-sheep in summer rotational grazing trail,trampling homogeneity trial,two-factor trail of simulated precipitation and experimental trampling.

Key words: Trampling, Trampling unit, Trampling equivalent unit, Trampling intensity, Experimental trampling, Model