论文部分内容阅读
以西北干旱区1990、1999、2007和2015年4个时期Landsat TM/ETM+/OLI遥感影像为基础,运用水体指数获取104个面积大于1 km2湖泊数据,并分析湖泊变化的驱动机制.研究表明:①1990～2015年西北干旱区湖泊面积整体呈“增加”的状态,其中1999～2007年湖泊面积扩张速度最明显;②西北干旱区湖泊整体呈扩张趋势,存在明显的区域差异,面积呈先减少后增加趋势的湖泊数量最多,分布也最广.面积持续减少的湖泊数量较少,团状分布在腾格里沙漠腹地;③降水和温度是影响湖泊变化的两个重要因素.高山湖泊面积变化稳定,湖泊面积变化与降水、温度和蒸发量具有较好的一致性,人类活动对湖泊面积变化影响微乎其微.而平原湖泊面积变化则受自然因素和人类活动共同影响.沙漠湖泊面积则是气候变化与地下水补给源变化共同作用的结果.研究整体提高西北干旱区湖泊时空变化特征的认知,并将为本区湖泊变化研究和环境保护提供合理依据.“,”Based on Landsat TM/ETM+/OLI remote sensing images in the arid region of Northwest China in 1990,1999,2007 and 2015,104 data of lakes with area greater than 1 km2 were obtained by Normalized Difference Water Index(NDWI)and the driving mechanism of lake change was analyzed.The results show that:(1)From 1990 to 2015,the lake area in northwestern arid region was increasing,and the area of lake in 1999～2007 was the most obvious;(2)In the northwest arid region,the whole lakes showed an expanding trend,but there were obvious regional differences.The area of the lakes decreased first and then increased,and the lakes were the largest and the most widely distributed.Area of the lake continued to reduce the number of small,was distributed in the hinterland of Tengger Desert;(3)Precipitation and temperature are two important factors influencing lake change.The change of lake area is consistent with precipitation,temperature and evaporation,and the impact of human activities on the change of lake area is insignificant.While the change of plain lake area is affected by natural factors and human activities.Desert lake area is the result of climate change and groundwater recharge source changes.The results promote to improve the temporal and spatial characteristics of the lakes in Northwest China,And provide a reasonable basis for the study of lake change and environmental protection in this area.