Characterization of spatial and temporal changes in water area in Kunming over the past 30 years

Abstract

Abstract Watershed area is an important indicator reflecting the status of water resources and changes in the water environment, and its changes have a significant impact on ecosystem function, hydrological cycle and climate change. This paper analyzes the characteristics and causes of the long time series changes of the watershed area in Kunming City by using PIE-engine remote sensing computing cloud service platform, based on Landsat TM/ETM+ remote sensing images, and adopting NDWI (Normalized Difference Water Index) index. The results show that the water area of Kunming City has shown a W-shaped trend in the past 30 years, with a dynamic fluctuation of decreasing and then increasing, then decreasing and then increasing. The change of water area in Kunming is mainly influenced by both natural and anthropogenic factors. Natural factors mainly include climate change, and anthropogenic factors mainly include urban expansion, development and utilization of urban water resources, land use changes, water conservancy project construction and environmental pollution. This paper provides an effective methodology and data support for the monitoring and protection of the watershed area in Kunming by analyzing the characteristics of the change of the watershed area in the past 30 years.