Chromophoric dissolved organic matter (CDOM) is the colored fraction of the dissolved organic carbon (DOC) pool. According to investigations and filed measurements in Lake Honghu, Lake Donghu, Lake Liangzi in September and October of 2007, optical characteristics and spatial distribution of CDOM in these lakes are analyzed. Results show that CDOM absorption coefficient in Lake Honghu is the highest, with the mean value of the CDOM absorption coefficient at 400nm (a g (400)) is 1.45m-1 , while the lowest is in Lake Liangzi, with the mean value of the CDOM absorption coefficient at 400nm is 0.68m-1. A significantly positive correlation between CDOM absorption coefficient and suspended sediment concentration is found in Lake Honghu. In Lake Liangzi, CDOM absorption coefficient is positive correlated with chlorophyll concentration, which means CDOM in the lake is mainly contributed by Phytoplankton degradation. The slope (S) in the exponential correlation function does not vary much in Lake Honghu and Lake Donghu. Fulivc acid is the dominated constituent of CDOM in Lake Liangzi, and the absorption coefficient of CDOM vary extremely. There is a negative correlation relationship (-0.9) between S and a g (400) in Lake Liangzi.

This study examines the spatio-temporal variations in the sea-surface chlorophyll-a (Chl-a) concentration and their associated underlying driving forces in the northern South China Sea (SCS) from 2004 -2010. A stratified analysis method and the Moderate Resolution Imaging Spectroradiometer (MODIS) Chl-a product, the National Centers for Environmental Prediction (NCEP) reanalysis data, with maps of monsoon winds and current systems were used in this work. Validation indicated that the MODIS-derived Chl-a is in good agreement with in-situ measurements (R 2 = 0.815), accurate enough for analyzing the temporal-spatial variations of Chl-a in the northern SCS. The results show that the spatial heterogeneity of the Chl-a concentration was lowest in winter and increased in spring. The seasonal Chl-a concentration dynamics varied spatially and depended predominantly on the distance from the coastline. The most important factors that affect the Chl-a concentration spatial variability were identified as the monsoon, surface current and sea surface temperature (SST).