青藏高原湖泊面积动态变化及其对气候变化的响应

Dynamic Change of Lake Area over the Tibetan Plateau and Its Response to Climate Change

为了探究整个青藏高原湖泊总面积变化的原因,本文利用RS和GIS技术,提取了1960 s—2015年青藏高原大于1 km2的湖泊数据,分析了近50年来青藏高原湖泊面积的动态变化,并结合相应的气象数据,通过相关性分析及回归分析等方法分析了影响湖泊面积变化的主要气象因子。结果表明:(1)青藏高原整体变暖湿的过程中大于1 km2湖泊的总面积呈现增长-减少-加速增长的趋势,从1960 s—2015年共增长了9138.60 km2,增长率为23.90%;(2)100~500 km2级别的湖泊总面积占青藏高原湖泊总面积的比重最大,各不同等级的湖泊总面积总体呈上升趋势;(3)青藏高原4500~5000 m海拔范围内的湖泊总面积最大,海拔4500~5000 m及海拔3000 m以下的湖泊面积变化较剧烈,呈现波动中增长的趋势,其余海拔范围内的湖泊面积基本维持稳定;(4)青藏高原西部地区和北部地区的湖泊总面积总体上呈现增长趋势,东部及南部地区湖泊总面积基本维持稳定,整个青藏高原湖泊面积变化的区域在空间上呈现扩张趋势;(5)年平均气温、年降水量及年蒸发量与湖泊面积呈现显著的相关性,研究区边缘地区湖泊面积和年平均气温有显著相关性,研究区中部地区湖泊面积同年平均气温、年降水量及年蒸发量有显著相关性,而研究区东北部及中西部部分地区湖泊面积和年平均气温及年蒸发量有显著相关性。通过气象因子与湖泊总面积的回归分析结果表明,年平均气温和年蒸发量变化是导致青藏高原湖泊总面积改变的主要原因。本研究填补了青藏高原长时间序列和多尺度的湖泊面积动态变化方面的空白,同时本研究得出的湖泊数据可以为其他研究人员提供一定的帮助。

In order to explore the RS and GIS techniques were used change of the total area of lakes in the Qinghai0-Tibet to extract the data of the lakes with areas larger than 1 Plateau, in this research km2 in the Qinghai-Tibet Plateau from 1960s to 2015, and the dynamic changes of the lake areas over the past 50 years were analyzed. Combined with the relevant meteorological data, it concluded the main meteorological factors affecting the changes of lake areas through the analysis of relevance and regression. The results showed that ： （ 1 ） in the overall process of warming and humidification of the Qinghai-Xizang Plateau, the total area of lakes greater than 1 km2 showed a trend of increase-decrease-accelerate. From 1960 s to 2015, the total area had increased by 9138.60 km2 with a growth rate of 23.90%. （2） The total area of lakes with areas between 100 - 500 km2 accounted for the largest proportion in all lakes in the Qinghai-Tibet Plateau. The total area of lakes at different area level generally showed an upward trend. （3） Lakes within the altitude range of 4500 -5000 m in the Tibetan Plateau occupied the biggest total area, whereas the lakes within the altitude range of 4500 - 5000 m and those below 3000 m sea level presented relatively drastic changes in areas, showing an increasing trend with fluctuation. The lakes within the remaining altitude ranges generally remained stable. （4） The total area of the lakes in the western and northern Tibetan Plateau showed an overall growth trend, but in the eastern and southern regions it remained basically stable, and the changes in the entire area of the lakes in the Qinghai-Tibet Plateau revealed a spatial expansion trend. （5） The annual mean temperature, annual precipitation and annual evaporation had a significant correlation with the lake areas. There was a significant correlation between the lake areas and annual average temperature in the border area of the study area. The lake areas in the central area of the study area had a significant correlation with the average temperature, annual precipitation, and annual evaporation. The study area and part of the central and western regions were areas of the lakes in the northeastern part of the significantly correlated with the annual average temperature and annual evaporation. According to the regression analysis on meteorological factors and the total lake area, changes in annual average temperature and annual evaporation were responsible for the changes in the total area of lakes in the Tibetan Plateau. This study fills the research gap on the dynamic changes of lake areas in the Tibetan Plateau from perspective of long time series and multi-scale, and the lake data obtained in this study can provide reference to other researchers.