基于MODIS的海州湾可溶性无机氮浓度遥感监测研究

Stndy on Dissolved Inorganic Nitrogen Monitoring Based on MODIS Imaging for Haizhou Bay

在海州湾海域,DIN质量浓度与MODIS影像第1、4波段的反射率呈正相关,与第2、3、5、6等波段的反射率呈负相关,这里既体现无机氮基团的吸收特征,也反映了叶绿素a和黄色物质质量浓度与DIN质量浓度间的密切的联系。在MODIS的波段组合因子中由蓝绿波段反射率构成的因子F11(3,4)与DIN质量浓度间的相关性达到0.85,由该因子建立的线性模型的平均相对预测精度接近70%,将该模型应用于影像反演,所得到的结果与该海域实际的DIN质量浓度时空分布规律相当吻合。

The reflectances of Band 1 and Band 4 for MODIS imaging are positively correlated with the mass concentration of DIN in Haizhou Bay while the reflectances of Bands 2,3,5 and 6 are negativey correlated with the DIN mass concentration.These correlation results reflect not only the absorption spectral characteristics of inorganic nitrogen but also the relationships among the mass concentrations of chlorophyll-a,yellow substance(CDOM),and DIN.The correlation coefficient between the DIN mass concentration and the combining factor F11(3,4) of Bands 3 and 4 in MODIS imaging can be as high as 0.85,and the relative accuracy in the results form a linear model including this factor becomes about 70%.The distribution of the DIN mass concentration retrieved by means of the model is well consistent with the actual temporal-spatial distribution in the bay area.