【摘要】 基于西藏高寒草原生态系统以水分为主要驱动力的东西样带和以温度为主要驱动力的南北样带内采集土样的实测数据,分析了表层(0~20cm)土壤活性有机碳的分布特征及其与气候因子之间的关系。结果表明,在28°46′-31°40′N的南北样带内,表层土壤活性有机碳含量随着纬度的增加而增加,当纬度增加到一定程度后,则随着纬度的增加而减少,呈现出南北低、中间高的分布特征。在80°02′-91°50′E的东西样带内,表层土壤活性有机碳含量随着经度的增加而增加,当经度增加到一定程度后,则随着经度的增加而减少,呈现出东西低、中间高的分布特征。影响南北样带内表层土壤活性有机碳分布的关键气候因子是年均气温,而影响东西样带内表层土壤活性有机碳分布的关键气候因子则是年均降水量。更多还原

【Abstract】 Based on the survey from the soil samples along the water-driven East and West Tibet Transect (EWTT) and the temperature-driven North and South Tibet Transect (NSTT) in Tibetan alpine grassland ecosystem, the distribution characteristics of topsoil (0-20cm) organic labile carbon and its correlation with climatic factors were investigated. It was shown that the topsoil labile organic carbon content first increased and then decreased along the latitude, peaking in the middle zone within NSTT ranging from 28°46’ to 31°40’ N. Interestingly, the distribution of topsoil labile organic carbon in EWTT exhibited a similar pattern ranging from 80°02’ to 91°50’ E, first increased then decreased along longitude. In NSTT, the annual average temperature was the key climatic factors influencing the distribution of the topsoil labile organic carbon, whereas the annual average rainfall played the critical role in EWTT.更多还原