内陆水体叶绿素反演模型普适性及其影响因素研究

利用具有较大时空差异性的水体组分和光学特性数据集对现有叶绿素半分析(三波段和四波段模型)和生物光学反演模型进行检验,研究叶绿素反演模型的普适性及其影响因素.结果表明,叶绿素生物光学分析反演模型具有较高的普适性,总体反演精度可以接受,但反演精度受叶绿素比吸收系数时空差异影响较大;三波段和四波段叶绿素反演模型反演精度较高,但是由于水体组分组成及其生物光学特性差异使得反演因子最佳波段位置和反演模型参数存在较大的变异性,大大降低了三波段和四波段叶绿素反演模型的普适性,其中后向散射系数光谱曲线形状和叶绿素比吸收系数是三波段和四波段模型普适性的主导影响因素.

Study on Influencing Factors and Universality of Chlorophyll-a Retrieval Model in Inland Water Body

The semi-analytical three-and four-band model and bio-optical analytical model of chlorophyll-a were checked by the water constituents and optical properties with high spatio-temporal variation. The influencing factors and universality of the retrieval model were studied by the modeling checking results. The study results indicate that the universality of bio-optical analytical model is much higher than the three-and four-band model, and the accuracy of the retrieval model is acceptable, but the accuracy of the retrieval model was highly affected by the specific absorption coefficient of chlorophyll-a. The accuracy of the three-and four-band model is higher than the bio-optical analytical model. However, the universality of the three-and four-band model is not very high, because of the optimal wavelength position of the retrieval factors and the greater variability of the retrieval model parameters. The spectral shape of particle backscattering coefficient and chlorophyll-a specific absorption coefficient are the dominant influencing factors of the three-and four-band retrieval model.