祁连山东段不同植被下土壤养分状况研究

通过分析祁连山东段天祝县地区5种植被类型（丛生禾草草地、银露梅灌丛、青海云杉林、青海云杉-白桦混交林和白桦林）覆盖下土壤碳、氮、磷含量的变化情况，研究了不同植被对土壤养分的影响。结果表明:植被对土壤养分具有表聚效应，不同植被覆盖下的土壤0-20 cm土层养分含量显著高于20-40 cm土层（p<0.05），乔木林的表聚效应强于灌丛和草地。随上覆植被从草本植物到灌木再到乔木的变化，土壤有机碳、全氮、铵态氮和速效磷等养分均呈现出逐渐增加的趋势（p<0.05）；硝态氮含量变化情况为白桦林>银露梅灌丛>青海云杉林>青海云杉-白桦混交林>丛生禾草草地，土壤全磷除白桦林下较高外，其他4种植被之间都无显著差异（p>0.05）。青海云杉-白桦混交林维持土壤养分平衡的能力强于其他4种植被。

Dynamics of Soil Nutrients under Different Vegetation Types in the Eastern Qilian Mountains

By analyzing carbon,nitrogen and phosphorus changes of 0-20 cm soil layer and 20-40 cm soil layer under the five vegetation types,we studied the effects of different vegetation on soil nutrients in Tianzhu County of the Eastern Qilian Mountain.The results indicated: vegetation can significantly improve the surface soil nutrient,and surface aggregation effect of arbor is stronger than shrub and grass.With the changes of vegetation from grass to shrub and then to arbor,soil organic carbon,total nitrogen,ammon...