基于哨兵2数据的2019-2021年三亚河水体透明度数据集

A dataset of water transparency of Sanya River based on Sentinel-2 data during 2019-2021

水体透明度是环保部门最关心的重要水质参数之一,反映水体浑浊程度,对水体初级生产力与水生态系统具有重要影响。作为典型海岛独立水系,海南省总体地表内陆水体水资源较丰富,河流径流充沛,但受干湿季风和地形影响具有时空分布不均的特点,目前针对海南岛内陆水体水质研究相对较少。本文以海南省三亚市三亚河为研究区,基于GEE云计算平台和Google云存储的哨兵2地表反射率数据,采用基于QAAv6的透明度半解析模型反演2019-2021年三亚河时间序列透明度。对于三亚河水体动态提取,采用归一化水体指数NDWI与OTUS自动化阈值分割相结合的算法提取细小河流水体。数据以GeoTiff栅格格式存储,同时保存了像元透明度值和坐标信息,便于相关的地理信息系统软件读取和分析。基于GEE云数据库反演水体长时序透明度,具有高效快速的优势。本数据集可以为三亚河水质监测、水体污染治理及水生态保护等提供重要科学依据。

As one of the most important water quality parameters on the radar screen of environmental protection sectors,water transparency reveals the turbidity degree of water and plays an important role in the primary productivity of water body and water ecosystem.As an independent island water system,Hainan Province has abundant surface inland water resources and plentiful river runoff.However,due to the influence of dry and wet monsoons and topography,the aquatic systems are characterized by uneven spatial and temporal distribution,and there are few studies on the water quality of inland water bodies on Hainan Island.In this study,we took Sanya River in Sanya,Hainan Province as the study area,and used the QAAv6-based semi-analytic model to retrieve the water transparency of Sanya River in time series from 2019 to 2021 based on the GEE cloud computing platform and the massive Sentinel-2 surface reflectance data stored in Google Cloud.With regard to the extraction of dynamic water area from Sanya River,we adopted the algorithm combining the normalized water body index NDWI with OTUS automatic threshold segmentation to extract the small river water.The data are stored in Geo Tiff raster format,and the pixel transparency value and coordinate information are stored at the same time for easy reading and analysis by relevant GIS software.The inversion of long time series transparency based on the GEE cloud database is highly efficient.The dataset can serve as valuable scientific evidence for the water quality monitoring,water pollution control,and aquatic ecological protection of Sanya River.