“珠海一号”采煤沉陷区叶绿素a浓度反演研究

Chlorophyll-a Concentration Inversion in Coal Mining Subsidence Area Based on OHS-1 Hyperspectral Image

"珠海一号"卫星高光谱数据具有高时空分辨率的特点,为采煤沉陷区水质时空监测提供了更高精度的数据源。叶绿素a浓度是评价水质状况的重要参数。为探究淮南采煤沉陷区叶绿素a浓度反演模型,以安徽淮南顾桥采煤沉陷区为研究对象,基于"珠海一号"高光谱影像和水样测试数据,对采煤沉陷水域叶绿素a浓度反演模型进行构建,反演并分析了顾桥采煤沉陷区叶绿素a浓度空间分布特征及其成因。结果表明:基于珠海一号高光谱影像(b10+b19-b2)/(b10+b19+b2)波段组合方式构建的三次函数模型精度和稳定性较高,可以用于顾桥采煤沉陷区水质的动态监测;顾桥沉陷区水域总体叶绿素a浓度较高,高值区主要位于水域中部,且南部水域高于北部;农田施肥和工矿生产、居民生活污水的排放是造成沉陷区内叶绿素a浓度上升的主要原因。

The hyperspectral data OHS-1 satellite,with the high spatial and temporal resolution,provides a more accurate data source for the spatial and temporal monitoring of water quality in mining subsidence area.Chlorophyll-a concentration is an important parameter to evaluate water quality.To explore the inversion model of chlorophyll-a concentration in Huainan coal mining subsidence area,the inversion model of chlorophyll-a concentration in the coal mining subsidence area was constructed,with Guqiao coal mining subsidence area in Huainan,Anhui province as the research object,and the spatial distribution characteristics of chlorophyll-a and its origin in the subsidence area were analyzed based on the hyperspectral image of OHS-1 satellite and water sampling data.The results show that the cubic function model based on(b10+b19-b2)/(b10+b19+b2)band combination from hyperspectral image of OHS-1 satellite has high inversion accuracy and stability,and can be used for dynamic monitoring of water quality in Guqiao coal mining subsidence area.The overall chlorophyll-a concentration in the water of subsidence area is high,mainly located in the middle part of the area,which in the southern part is higher than in the northern part.The main reasons for the increase of chlorophyll-a concentration in the subsidence area are the fertilization of farmland,the discharge of the industrial and mining production and the domestic sewage.