Post‐Impoundment Biomass and Composition of Phytoplankton in the Yangtze River

Abstract

Damming, and thus alteration of stream flow, promotes higher phytoplankton populations and encourages algal blooms (density >10 6 cells L -1 ) in the Three Gorges Reservoir (TGR). Phytoplankton composition and biomass were studied in the Yangtze River from March 2004 to May 2005. 107 taxa were identified. Diatoms were the dominant group, followed by Chlorophyta and Cyanobacteria. In the Yangtze River, algal abundance varied from 3.13 × 10 3 to 3.83 × 10 6 cells L -1 , and algal biomass was in the range of 0.06 to 659 mg C m -3 . Levels of nitrogen, phosphorus and silica did not show consistent longitudinal changes along the river and were not correlated with phytoplankton parameters. Phytoplankton abundance was negatively correlated with main channel discharge (Spearman r = -1.000, P < 0.01). Phytoplankton abundance and biomass in the Yangtze River are mainly determined by the hydrological conditions rather than by nutrient concentrations.

Hydrological changes and ecological impacts associated with water resource development in large floodplain rivers in the Australian tropics

“…Our approach adds to this 'tool box' of hydrological change prediction and is appropriate not only for Australia but also many other regions where WRD is still increasing. In Central and South America and northern Asia, the damming of tropical rivers for hydroelectric power, navigation and water diversion is an ongoing concern for the ecological integrity of these rivers (Dudgeon, 2000;Anderson et al, 2006a;Anderson et al, 2006b;Zengi et al, 2007). Our findings will have important implications for future decisions concerning the natural resource management of rivers in the Australian tropics and rivers displaying similar characteristics elsewhere in the world.…”

Assessing the influence of environmental impact assessments on science and policy: An analysis of the Three Gorges Project

“…However, this prediction has been dismissed by some due to the steep shorelines that provide little habitat for the snail (Jobin, 2005). Upstream of the dam, occurrence of algal blooms within the TGP reservoir have been attributed to increases in residence time (Zeng et al, 2007b). Secondary impacts also extend to other parasitic fauna upstream of TGP, with the reservoir predicted to encourage the proliferation of a fish tapeworm (Bothriocephalus acheilognathi) (Morley, 2007).…”

Can Hydrodynamics Change Phosphorus Strategies of Diatoms?—Nutrient Levels and Diatom Blooms in Lotic and Lentic Ecosystems

“…Diatom blooms are observed worldwide in both lotic (e.g., rivers) [20,35,41] and lentic ecosystems (e.g., lakes and ponds) [31,47,79]. Many studies have found differences in the dominant diatom species among different types of freshwater ecosystems.…”