近30年青藏高原可可西里盐湖面积动态变化及其影响因素分析

Dynamic changes of Yanhu Lake in Hoh Xil area on Qinghai-Tibet Plateau in recent 30 years and analysis of its influencing factors

青藏高原湖泊是全球气候变化的敏感指标,对全球气候变化具有很强的反馈作用。由于卓乃湖的溃堤,地处于青藏高原腹地的可可西里盐湖迅速扩张,这不仅对周边草地植被及流经的冻土造成危害,对青藏铁路和青藏公路的正常运行也产生了干扰。本文利用多源遥感监测手段对可可西里盐湖近30年面积进行监测,从时空变化趋势上提取盐湖面积的动态变化并进行成因分析。结果表明:(1)2011年9月卓乃湖溃决,导致可可西里盐湖面积1990—2020年增大了178.535 km^(2);(2)自2020年可可西里盐湖的引流工程完工,盐湖面积得到有效遏制,并在2021年缩小至191.145 km^(2);(3)盐湖湖岸线自1990—2020年主要在东南部和西南部有显著扩张,而最大的变化是盐湖东部由以前伸入湖中央的半岛变为孤岛;(4)面积与降水、气温呈显著相关关系,与日照时长、冰川融水呈弱相关关系。

The lakes on the Qinghai-Tibet Plateau are sensitive indicators of global climate change and have a strong feedback effect on global climate change.Due to the breakwater of Zhuonai Lake,the Yanhu Lake of Hoh Xil,located in the hinterland of the Qinghai-Tibet Plateau,is expanding rapidly,which not only harms the surrounding grassland vegetation and the permafrost flowing through,but also interferes with the normal operation of the Qinghai-Tibet railway and the Qinghai-Tibet highway.In this paper,multi-source remote sensing monitoring means are used to monitor the Yanhu Lake in Hoh Xil area in recent 30 years,and the dynamic changes of the area of the Yanhu Lake are extracted from the trend of temporal and spatial changes,and the causes are analyzed.The results show that:①The collapse of Zhuonai Lake in September 2011 increased the Yanhu Lake of Hoh Xil by 178.535 km^(2)from 1990 to 2020.②Since the completion of the diversion project of Yanhu Lake in Hoh Xil area in 2020,the area of the Yanhu Lake has been effectively contained and will be reduced to 191.145 km^(2)in 2021.③The shoreline of the Yanhu Lake has expanded significantly in the southeast and southwest from 1990 to 2020,and the biggest change is that the eastern part of the Yanhu Lake has become an island from the peninsula that once stretched into the center of the lake.④The area has a significant correlation with precipitation and temperature,and a weak correlation with sunshine duration and glacial melt water.