若尔盖高寒退化草地土壤有机碳储量空间分异特征

The Soil Organic Carbon Storage and Its Spatial Characteristics in an Alpine Degraded Grassland of Zoige,Southwest China

试验采用野外调查取样法分层测定0-30cm土壤7月、10月有机碳储量、含水量和容重,并测定高原鼠兔洞穴密度。结果显示,牧草枯黄期（10月）土壤有机碳储量显著高于生长旺盛期（7月）（P〈0.05）;5个样地平均土壤有机碳储量为0.33-0.70kg/m^2;7月时,空间等距离分布的5个样地土壤表层有机碳储量坡地区（样地Ⅰ、Ⅱ、Ⅲ）向平地区（样地Ⅳ、Ⅴ）呈递增趋势,差异显著（P〈0.05）;土壤有机碳储量随土层深度的增加递减,且差异达到极显著水平（P〈0.01）;土壤有机碳储量与含水量呈显著正相关（P〈0.05）,与土壤容重呈显著负相关（P〈0.05）,与高原鼠兔洞穴密度无显著相关性。

Based on the analysis of soil organic carbon storage and its correlation analysis with environmental factors in an alpine degraded grassland of Zoige,which were helpful for understanding the grassland nutrient cycling processes,plateau pika control and wetland management strategies.The SOC storage,soil water percentage and soil bulk density in 0-40cm soil depth in July and October were measured by field method of stratified sampling.The results were as follows,the SOC storage in October was significantly higher than that in July（P〈0.05）.The mean SOC storage was between 0.33-0.70kg/m^2 in the five plots,and in July SOC storage was significantly higher in plots on the flat areas compared with plots on sloping ground.SOC storage decreased with soil depth.SOC storage was positively related to water percentage（P〈0.05）,but negatively related to soil bulk density（P〈0.05）.Moreover,it had no obvious relationship with pika burrow densities.