Dynamics of suspended solids in Xiangxi Bay of Three Gorges Reservoir during spring algal bloom period.

The dynamics of total suspended solids (TSS) in Xiangxi Bay of Three Gorges Reservoir (TGR) during the period of spring algal bloom were weekly investigated. The results showed that the TSS in the Bay ranged from 0.66 to 134.92 mg . L-1, with a median of 6.80 mg . L-1, and tended to be increased from headwater to down-lake zones. The spatial pattern of non-volatile suspended solids (NVSS) was similar to that of TSS, while volatile suspended solids (VSS) showed obviously different pattern from TSS and followed the spatial pattern of chlorophyll a. Regression analysis indicated that in the mid-zone of the Bay, chlorophyll a was significantly related to TSS and VSS, and explained 66.7%-96.7% and 58.9%-85.5% of the variance in TSS and VSS, respectively. In the headwater and down-lake zones, there were no significant relationships between chlorophyll a and TSS (including NVSS and VSS). The TSS in mid-lake had more close relationship with VSS than with NVSS, while that in headwater and down-lake had more close relationship with NVSS than with VSS, implying that the mid-lake of Xiangxi Bay was a more autochthonous system than the headwater and down-lake where allochthonous influences were the more determinant factors