Spatial-temporal Variations in Lakes in Central Yunnan Province from 1987 to 2017

Abstract

Lake spatial-temporal variations are sensitive records of climate and environmental changes, directly reflecting global changes. Lakes have great ecological and economic benefits, which play an important role in improving the ecological environment of the river basin, regulating surface and underground runoff, irrigating farmland, breeding aquatic animals and plants, maintaining biodiversity, flood control and disaster reduction, and producing and drinking water. In this paper, we took lakes in central Yunnan province as the research object, based on Landsat TM, ETM+ and OLI remote sensing images data in the period from 1987 to 2017, the vectorized boundary of 5 lakes with areas greater than 30 km2 in central Yunnan were obtained by artificial visual interpretation technology and the causes of lake variations were analysed. Several conclusions can be drawn from the present study: (1) From 1987 to 2017, the total lake area in central Yunnan increased from 603.86km2 to 605.71km2.(2) During the study period, the lake area in central Yunnan increased as a whole, but also showed obvious spatial differences. According to the change of lake area, the study area can be divided into three types: stable, expanding and shrinking. Dian chi lake area is a lake area expanding area. Yang zonghai lake area is a shrinking lake area. (3) Influenced by the complex natural and cultural environment in the study area, the reasons for the change of lake area in different areas are different.