Are There Sufficient Landsat Observations for Retrospective and Continuous Monitoring of Land Cover Changes in China?

作者：Yan Zhou, Jinwei Dong, Jiyuan Liu, Graciela Metternicht, Wei Shen, Nanshan You, Guosong Zhao, Xiangming Xiao · 发表于：Remote Sensing · 年份：2019 · DOI：10.3390/rs11151808 · 被引用次数：35 · 研究领域：Remote Sensing in Agriculture、Land Use and Ecosystem Services、Remote Sensing and Land Use

Unprecedented human-induced land cover changes happened in China after the Reform and Opening-up in 1978, matching with the era of Landsat satellite series. However, it is still unknown whether Landsat data can effectively support retrospective analysis of land cover changes in China over the past four decades. Here, for the first time, we conduct a systematic investigation on the availability of Landsat data in China, targeting its application for retrospective and continuous monitoring of land cover changes. The latter is significant to assess impact of land cover changes, and consequences of past land policy and management interventions. The total and valid observations (excluding clouds, cloud shadows, and terrain shadows) from Landsat 5/7/8 from 1984 to 2017 were quantified at pixel scale, based on the cloud computing platform Google Earth Engine (GEE). The results show higher intensity of Landsat observation in the northern part of China as compared to the southern part. The study provides an overall picture of Landsat observations suitable for satellite-based annual land cover monitoring over the entire country. We uncover that two sub-regions of China (i.e., Northeast China-Inner Mongolia-Northwest China, and North China Plain) have sufficient valid observations for retrospective analysis of land cover over 30 years (1987–2017) at an annual interval; whereas the Middle-Lower Yangtze Plain (MLYP) and Xinjiang (XJ) have sufficient observations for annual analyses for th...