青藏高原东部山地草地土壤碳、氮、磷元素计量特征  

The stoichiometric characteristics of soil C, N, P in mountain steppe of eastern Tibetan Plateau

作　　者：赵云飞 洪苗苗[1] 欧延升 黄政[1] 张洋洋[1] 汪霞[1,2] ZHAO Yunfei;HONG Miaomiao;OU Yansheng;ZHANG Yangyang;WANG Xia(College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China;Key Laboratory of Western China’s Environmental Systems with the Ministry of Education,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学资源环境学院,兰州730000 [2]兰州大学西部环境教育部重点实验室,兰州730000

出　　处：《生态科学》2018年第5期25-32,共8页Ecological Science

基　　金：国家自然科学基金(NSFC41572332);科技部基础资源调查专项(SQ2016FY491000803)

摘　　要：以青藏高原东部山地草地作为研究对象,分析了0—30 cm土壤层有机碳(C)、全氮(N)、全磷(P)化学计量特征,并探讨其与纬度、海拔、年均气温、年降水量、干旱因子之间的关系。结果表明:(1)在土壤垂直剖面上,土壤C、N含量变异性较大,表层土壤含量高于底层;土壤P含量垂直变异性较小,各土壤层间没有显著差异;土壤C:N变化范围为7.52—18.47、均值为11.62,比较稳定,各土壤层间没有显著差异;土壤C:P变化范围为22.86—156.76,均值为62.06,N:P变化范围1.02—9.92,均值为4.85,C:P和N:P比值随土层加深显著降低。(2)土壤C含量与N含量极显著正相关(P<0.01),随海拔、年降水量、干旱指数的增大而增大,而随年均气温的增加而降低;土壤P与环境因子没有显著关系。(3)土壤C、N、P含量及其比值在纬度梯度上没有规律性变化。土壤C:P和N:P比值随海拔的升高而增大,说明在青藏高原东部沿纬度分布的山地草地中土壤磷有效性随海拔的升高而降低;C:N比值相对稳定,受环境因子的影响较小。To explore the relationship between soil stoichiometric characteristics and latitude,altitude,mean annual temperature,mean annual precipitation and aridity index in mountain steppe,the study collected soil samples from mountain steppe of eastern Tibetan Plateau.The experiments of soil organic carbon(C),total nitrogen(N)and total phosphorus(P)were carried in the laboratory.The results showed that C and N content had larger variability in vertical soil profiles,and the contents of it in the surface soil were higher than in the sub-layer.The P content had slight variability in vertical soil profiles and had no significant difference in different soil layers.The soil C:N ratio was relatively stable in the range of 7.52-18.47 and averaged 11.62.The C:P ratio ranged from 22.86 to 156.76 and averaged 62.06.N:P ratio ranged from 1.02 to 9.92 and averaged 4.85.C:P ratio and N:P ratio were shown to decrease with the soi1 depth.The soil C content was a significant correlation with N content(P<0.01),and their variations were consistent.Soil C and N increased with altitude,mean annual precipitation and aridity index,and decreased with mean annual temperature while soil P content was not correlated with environmental factors.The study concluded that there was no significant correlation between C,N,P and their ratios and latitude.Soil C:N ratio was relatively stable,and was not correlated with environmental factors(P>0.05).Soil C:P and N:P ratio decreased with altitude,which indicated that soil P availability decreased with altitude in this research area.

关 键 词：青藏高原 山地草地 碳氮磷 化学计量学特征 气候因子 地理因子 

分 类 号：S153.6[农业科学—土壤学]