基于多源遥感数据的大襟岛海域叶绿素a反演及富营养化评价

本研究基于实测的Chl-a质量浓度和海表面光谱数据，构建了适用于CASI(Compact Airborne Spectrographic Imager)航空高光谱和MODIS(Moderate-resolution Imaging Spectroradiometer)卫星遥感影像的Chl-a反演模型，并在研究海域开展了Chl-a质量浓度的反演。研究结果表明，基于CASI影像的波段比值模型可以较好地反演出研究海域的Chl-a质量浓度，研究海域内Chl-a含量为0.1~4.4 μg/L，平均相对误差为14.58%；基于MODIS卫星影像反演获得的珠江口Chl-a质量浓度为0~8 μg/L，平均相对误差为17%。总体而言，大襟岛海域整体Chl-a质量浓度的分布比较均匀，而且含量较低；基于Chl-a质量浓度计算获得卡尔森营养状态指数表明，研究海域处于贫营养化和中营养化水平，复杂水动力环境和高浊度可能是抑制研究海域浮游植物生长的主要因素。

Chlorophyll-a retrieval and eutrophication assessment of sea area around the Dajin Island based on multi-source remote sensing images

Based on the measured Chl-a concentration and sea surface spectrum, the Chinese white dolphin inhabited area of Dajin Island in the Pearl River Estuary was taken as the study area, a Chl-a inversion model suitable for CASI aerial hyperspectral and MODIS satellite remote sensing images was constructed and Chl-a concentration inversion was carried out. The results show that the band ratio model has better performance based on CASI images. The Chl-a concentrations in the study area are 0.1-4.4 μg/L, and the relative average error is 14%. Inversed with MODIS, the Chl-a concentrations in the Pearl Estuary vary from 0 to 8 μg/L with relative average error of 17%. In general, the Chl-a in the sea water around Dajin Island is uniformly low. The Carlson eutrophic index calculated based on the concentration of Chl-a indicates that the sea area around Dajin Island is at the level of oligotrophic and mesotrophic, the complex hydrodynamic and high turbidity may be the main factors inhibiting the growth of phytoplankton in the study area.