高分一号WFV影像的深圳市水库COD_(Mn)浓度时空分布特征  

Study of spatial—temporal characteristics for COD_(Mn) in Shenzhen reservoir based on GF-1 WFV

作　　者：李俊 张文志[4] 邓孺孺[1,2,3] 鲁志文 梁业恒[1] 沈雪娇[4] 熊龙海[1] 刘永明 LI Jun;ZHANG Wenzhi;DENG Ruru;LU Zhiwen;LIANG Yeheng;SHEN Xuejiao;XIONG Longhai;LIU Yongming(School of Geography and Planning,Sun Yat-Sen University,Guangzhou 510275,China;Guangdong Engineering Research Center of Water Environment Remote Sensing Monitoring,Guangzhou 510275,China;Guangdong Provincial Key Laboratory of Urbanization and Geo-Simulation,Guangzhou 510275,China;Huizhou branch of Guangdong Hydrology Bureau,Huizhou 516003,China)

机构地区：[1]中山大学地理科学与规划学院,广州510252 [2]广东省水环境遥感监测工程技术研究中心,广州510253 [3]广东省城市化与地理环境空间模拟重点实验室,广州510254 [4]广东省水文局惠州水文分局,惠州516003

出　　处：《遥感学报》2022年第8期1562-1574,共13页NATIONAL REMOTE SENSING BULLETIN

基　　金：广东省省级科技计划项目(编号:2017B020216001);广东省水利科技创新项目(编号:2016-08);国家自然科学基金项目(编号:41071230,41901352);惠州市智慧河长卫星遥感监测服务项目(编号:440000-201903-197019009-0001)。

摘　　要：COD_(Mn)是反映水体有机污染程度的一个重要水质参数。地表水有机污染遥感监测主要面临两个挑战:技术方法大多基于经验模型,依赖大量实测数据;有机污染评价的综合性指标,水质参数不明确。针对上述问题,本文从辐射传输机理出发,基于研究区水体特征,考虑悬浮泥沙、叶绿素、耗氧性有机物3大水质因子,提出一种反演机理清晰、参数意义明确的像元反射率与COD_(Mn)浓度的物理模型。通过深圳市3大水库COD_(Mn)浓度反演与验证,决定系数R~2达到0.832,模型方法可靠明。对3大水库COD_(Mn)浓度时空分布特征研究,结果表明:(1)3大水库总体COD_(Mn)浓度不高,受到轻度有机污染。(2)浓度高值区多在库角居民区附近,水库连接处未出现污染扩散。(3)2018年3月—2019年5月,库区水质改善,与2018年深圳市治水专项活动背景保持一致,建议水库水质保护核心是控制外源污染,避免丰水期污染源的输入。本文的模型方法是基于广东省典型水体光学参数,而水体固有光学特征具有季节差异,未来将进一步研究水体固光学特征变化模式,以提高模型的稳健性。此外,还可结合高分六号等谱段更多的卫星开展浅水区COD_(Mn)浓度反演的研究。Permanganate index (COD_(Mn)) is an important water quality parameter to reflect the degree of organic pollution.At present,the retrieval of organic pollution by remote sensing technology is mostly based on empirical models and requires considerable manpower for data collection.Meanwhile,it has time and space limitations because it cannot process each image under different imaging conditions adaptively.The integrated water quality index,CDOM,and DOC of the inverted parameters are not water quality indexes.Thus,they cannot be directly used for actual water quality evaluation.Therefore,a novel quantitative remote sensing technology method for the retrieval of water permanganate index with clear understanding on mechanism is proposed.The method based on the radiation transmission process of electromagnetic waves and the characteristics of the water body in the study area consider the three major water quality factors of suspended sediment,chlorophyll,and oxygen-consuming organic,analyze the absorption and scattering coefficients of oxygen-consuming organic matter,and separate the contribution of the water column to the remote sensing signal from the effect of the bottom.The diffuse extinction coefficients (c) of water quality components are expressed as functions of in-water absorption (a) and scattering (b).Finally,the concentration of COD_(Mn)was derived with the remote-sensing reflectance below the surface (r).The experiment on the GF-1 Wide Field of View (WFV) imageries of the three major reservoirs in Shenzhen shows that the model method is reliable with overall accuracy of R~2=0.832 and RMSE=46.4%.The spatial—temporal characteristics of the three major reservoirs in Shenzhen during 2018—2019 were investigated.The overall COD_(Mn)concentration of the three major reservoirs is low with average COD_(Mn)concentrations of less than 4 mg/L;it is affected by mild organic pollution.No pollution diffusion occurred at the junction of the reservoirs,and the peak concentration mostly appeared near the residential area

关 键 词：COD_(Mn) 有机污染 吸收系数 GF-1 WFV 深圳 水质遥感 

分 类 号：X524[环境科学与工程—环境工程] X87