QUARTERLY MONITORING OF SUSPECTED ILLEGAL HUMAN ACTIVITIES IN NATIONAL NATURE RESERVES OF CHINA WITH SENTINEL-2 AND HIGH-RESOLUTION IMAGES ON THE CLOUD PLATFORM

Abstract. Nature reserves play an important role in protecting biodiversity, preserving natural heritage, and maintaining national ecological security. Satellite remote sensing technology has become an essential way to capture the impact of human activities on nature reserves by monitoring the land cover change. However, current monitoring frequency and scale were inadequate to detect the land change related to illegal human activities rapidly and accurately. To solve the above problems, this study proposed an operational suspected illegal change detection method which combined the temporal advantage of Sentinel-2 double satellites with the spatial advantage of high-resolution images from SiweiEarth and Google Earth cloud platforms, together with high-precision high-resolution images from cloud platforms, historical land cover data from Geoinformation Survey Data of China, and the thematic information of study area. Eight typical national nature reserves were selected as study areas. January 1st, 2019 was taken as the time point of the base period. May 31st, August 31st, and November 30th were taken as the time point of the first period, the second period, and the third period respectively. Results showed that four national nature reserves had nine suspected illegal land change parcels, with a good ecological protection situation of the other four nature reserves. Deforestation and illegal construction were the two main suspected illegal types. In the next step, the study results will be provided to the Law Enforcement Administration of China to evaluate the applicability and generalization of this method, and a more rapid and intelligent method needs to be improved.