不同放牧强度下西藏高山嵩草草甸土壤养分的变化  

Effects of grazing intensity on soil nutrient of Kobresia pygmaea meadow in Tibet Plateau

作　　者：苏振声 孙永芳[1] 付娟娟[1] 褚希彤[1] 许岳飞[1] 呼天明[1] 

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100

出　　处：《草业科学》2015年第3期322-328,共7页Pratacultural Science

基　　金：西北农林科技大学基本科研业务费专项基金项目(QN2011100);国家科技支撑计划项目(2011BAD17B05)

摘　　要：以西藏高山嵩草(Kobuesia tygmaea)草甸土壤为研究对象,分析不同放牧强度下土壤中全氮、全磷、全钾,速效氮、速效磷、速效钾,有机质及p H值的变化。结果表明,随着放牧强度的增加,在不同土层中,全氮、速效氮和速效钾含量减少;而全钾含量随着放牧强度的增加呈现先增加后减小的趋势;重度放牧显著降低了土壤中全氮、速效氮和速效钾的含量(P<0.05);随着放牧强度的增加,土壤有机质含量逐渐减少;放牧强度对土壤p H值影响没有显著影响(P>0.05)。因此,延迟+适度放牧和适度放牧可以有效地保护草地,防止高山嵩草草甸进一步退化。The present study was to investigate the effects of grazing intensity on soil organic matter,p H,total nitrogen,available nitrogen,total phosphorus,available phosphorus,total potassium,and available potassium in soil of Kobresia pygmaea meadow community of Tibet plateau.The results showed that the contents of soil total nitrogen,available nitrogen and available potassium decreased,while the contents of total potassium increased firstly and then decreased with the increasing of grazing intensity.Heavy grazing intensity significantly reduced the contents of total nitrogen,available nitrogen,available potassium and available phosphorus( P < 0.05).Soil organic matter content decreased gradually with the increase of grazing intensity.There was no significant difference between grazing and control in soil p H( P > 0.05).The results suggested that delayed grazing with moderate grazing intensity could protect grassland from degeneration.

关 键 词：放牧梯度 牦牛 土壤养分 西藏高原 

分 类 号：S812.2[农业科学—草业科学]