1986-2015年青藏高原哈拉湖湖泊动态对气候变化的响应

Response of lake dynamics to climate change in the Hala Lake Basin of Tibetan Plateau from 1986 to 2015

湖泊是气候变化的敏感指示器,研究其动态变化对揭示全球气候变化具有重要意义。以哈拉湖流域为研究区,基于3S技术提取流域内湖泊面积、形状等信息,揭示近30年哈拉湖流域湖泊动态变化特征,并探讨其对气候变化的响应。结果表明:1986-2015年间,哈拉湖流域湖泊面积变化呈"V"型,其动态变化大致可分为两个阶段:波动下降阶段(1986-2001年)和波动上升阶段(2001-2015年)。其中1986-2001年湖泊面积由593.68 km^(2)减少到584.83 km^(2)(减少8.85 km^(2));2001-2015年由584.83 km2增加到614.31 km^(2)(增加29.48 km^(2))。对湖泊面积变化量与冰川面积变化量及同期遥感数据阶段各气候要素相关分析发现,湖泊面积变化量与阶段降水量呈正相关,且相关显著性水平在0.01以上,进而降水量是湖泊动态变化的主导因素。

Lakes are sensitive indicators of climate change, and studying their dynamics is important for revealing global climate change. This study selected the Hala Lake Basin in the northeastern Qinhai-Tibet Plateau as a study area, and examined the relationships between the temporal and spatial changes of lake in the Northeastern Qinghai-Tibet Plateau and the climate change based on remote sensing imagery, climatological data, and topographic data from 1986 to 2015. Results showed that the lake area change presented a "V"-shaped pattern in the Hala Lake Basin during the study period. The dynamic change process can be divided into two stages: The stage of volatility decline(1986-2001) and the stage of volatility rise(2001-2015).The lake area decreased from 593.68 km2 in 1986 to 584.83 km^(2) in 2015(with a reduction of8.85 km^(2)) and increased from 584.83 km^(2) in 2001 to 614.31 km^(2) in 2015(with an increase of29.48 km^(2)). Correlation analysis between changes in lake and glacial areas and climatic factors in the same period of remote sensing data shows that the change of lake area is positively correlated with the stage precipitation, and the relevant significance level is above 0.01. The dominant factor of the dynamic change of lake is precipitation.