Influences of alpine ecosystem degradation on soil temperature in the freezing-thawing process on Qinghai-Tibet Plateau
Influences of alpine ecosystem degradation on soil temperature in the freezing-thawing process on Qinghai-Tibet Plateau
复制标题
青藏高原冻融过程中高山生态系统退化对土壤温度的影响
DOI：
10.1007/s00254-008-1417-7
复制
发表时间：
2009-05-01
期刊：
影响因子：
--
通讯作者：
Wang, Junfeng
中科院分区：
文献类型：
--
作者：
Hu, Hongchang;Wang, Genxu;Wang, Junfeng
高山生态系统对全球和局部干扰造成的环境变化非常敏感。青藏高原正在发生以植被覆盖度或生物量减少为特征的高山生态系统退化，改变了当地的能量平衡以及水和生化循环。然而，文献中缺乏对生态系统退化效应的详细描述。在这项研究中，研究了高山生态系统退化对季节性冻土和永久冻土土壤温度的影响。植被覆盖度用来表示生态系统退化的程度。对于不同的植被覆盖度，对永久冻土和季节性冻土的不同深度进行每日土壤温度监测。结果表明，在植被的隔热作用下，冻融过程变得更快、更陡，并且由于植被的隔热作用，冻融过程的起始时间提前。植被覆盖度对冻结过程的影响比解冻过程的影响更明显；随着植被覆盖度的减少，季节性冻土的冻深积分增加，而多年冻土则相反。
The alpine ecosystem is very sensitive to environmental change due to global and local disturbances. The alpine ecosystem degradation, characterized by reducing vegetation coverage or biomass, has been occurring in the Qinghai-Tibet Plateau, which alters local energy balance, and water and biochemical cycles. However, detailed characterization of the ecosystem degradation effect is lack in literature. In this study, the impact of alpine ecosystem degradation on soil temperature for seasonal frozen soil and permafrost are examined. The vegetation coverage is used to indicate the degree of ecosystems degradation. Daily soil temperature is monitored at different depths for different vegetation coverage, for both permafrost and seasonal frozen soils. Results show that under the insulating effort of the vegetation, the freezing and thawing process become quicker and steeper, and the start of the freezing and thawing process moves up due to the insulating effort of the vegetation. The influence of vegetation coverage on the freezing process is more evident than the thawing process; with the decrease of vegetation coverage, the integral of frozen depth increases for seasonal frozen soil, but is vice versa for permafrost.