草原区沙地草地植物的避牧性

Grazing Avoidance of Sand Pasture Plants in Steppe Zone

以浑善达克沙地草地为研究对象，研究了74种草地植物的避牧性．74种沙地草地植物的避牧强度变动于0．36～1．00．其中避牧强度为1的有21种，为0．90～0．99的34种，为0．80～0．89的11种，为0．70～0．79的4种，≤0．70的4种．根据沙地草地植物的避牧强度，将74种草地植物划分为4种类型，即强度避牧植物、中度避牧植物、弱避牧植物和不避牧植物．植物避牧的机制主要有化学避牧机制、低频度避牧机制、低矮型避牧机制、粗糙型避牧机制．植物的避牧性与其盖度、高度、密度、频度、产量、优势度具有一定的负相关性（P〈0．05）．

The grazing avoidance of 74 species of plants in sand pasture in steppe was studied. The results showed that grazing avoidance intensity of all studied plants ranged from 0.36 - 1.00. The plant species, that were with the grazing avoidance intensity 1.00, 0. 90 - 0. 99, 0. 80 - 0. 89, 0.70 - 0. 79, and 0.70, were 21,34, 11, 4 and 4, respectively. The plants with different grazing avoidance intensity were divided into 4 groups： plants with high, middle, low, and without grazing avoidance intensity. The mechanism of the grazing avoidance would be the mechanism with chemical materials, low appearance frequency, low height growth, or rough configuration characteristics. The grazing avoidance of plant was negatively related with its coverage, height, density, frequency, aboveground biomass, and dominance （P 〈0.05）.