Spatio-Temporal Changes in the Northeastern Coast of China in Recent 10 Years Based on Google Earth Engine and Intelligent Image Processing Technology—A Case Study of Heilongjiang Province and Shandong Province

Abstract

Water is a very important resource, which plays an important role in human life and production. Rapid and accurate water body information acquisition is of great significance for national resource management, planning, development, and rapid disaster assessment. The purpose of this paper is to explore and analyze the temporal and spatial changes of water bodies in the northeastern coastal areas of China in recent 10 years. Taking shandong province and heilongjiang province as the research area, Based on Google Earth engine, we used Landsat5, 7 and 8 images as data sources, comparing various water extraction methods, we finally selected the modified normalized water index model (MNDWI) to extract water, study the dynamic changes of water in ten years, and use supervised classification method to verify the accuracy. According to the results, the total water area in Shandong province decreased from 13067.08km2 in 2010 to 9418.58km2 in 2020, with an area decrease of 27.92%. The total water area of Heilongjiang province increased from 6154.782174km2 in 2008 to 7179.088516 km2 in 2018, an increase of about 14%. Then, according to the change of water area, the influencing factors are analyzed from natural and human perspectives. It is of great theoretical and practical significance for protecting and utilizing water resource by study the temporal and spatial changes of water bodies.