关键词: 红树林, 时滞现象, Granier热消散式探针法, 环境因子调控, 蒸腾

Abstract: There exists spatial heterogeneity in the water environment in different areas of the Three Gorges Reservoir Area (TGRA) after impoundment. In order to explore the effects of different water environmental conditions on the heavy metals concentrations in the fishes in TGRA, we selected the river mouth (Wushan) and backwater area (Dachang) of Daning River, a typical tributary in central TGRA, as the study areas. Eleven fish species were collected from each of the two sites, and the Cr, Cd, As, Pb, Ni, Cu and Zn concentrations in the muscle tissue of all fish samples were determined. The food sources and nutrition levels of the fish samples were evaluated by using stable isotope analysis (δ¹³C and δ¹⁵N). It was found that the fishes in Dachang had greater range of δ¹³C values (-28.8‰--22.5‰) than those in Wushan (-26.2‰--23.1‰), while the δ¹⁵N values of the fishes in Dachang were lower than those in Wushan. There were no significant differences in the heavy metal concentrations in the fishes in Dachang and Wushan, but the heavy metal concentrations in demersal fishes in Dachang were significantly higher than those in corresponding species in Wushan. As compared with other fishes, the demersal fishes in backwater water area had more contact with sediments, which could be an important reason for the higher heavy metal levels in the demersal fish tissues.

Key words: mangrove forest, transpiration, environmental regulations., timelag phenomenon, Grainer’s thermal dissipation probe method