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

摘要： 践踏是放牧家畜对草地的三大影响因素之一,也是导致草原全面退化的主要原因。但是由于技术和方法的限制,相关报道较少,极大地削弱了对草地农业生态系统的主体-草畜界面生态动力机制的整体认识。基于此,在我国干旱半干旱的黄土高原典型草原区兰州大学环县草畜生产系统野外实验点,通过滩羊夏季轮牧试验践踏强度的跟群观测、践踏同质性试验、模拟降水与试验践踏双因子试验进行了为期2年的系列研究。

关键词: 践踏, 践踏单位, 践踏当量, 践踏强度, 试验践踏, 模型