Chinese researchers have discovered that dam construction could damage the ecosystem in a long period of time through a case study at a branch of the Yangtze River in Three Gorges Area.
Wu Naicheng from Institute of Hydrobiology, Chinese Academy of Sciences (CAS) published his findings in the Journal of the North American Benghological Society with the title "Changes in benthic algal communities following construction of a run-of-river dam".
Wu and his colleagues examined the responses of the benthic algal communities in downstream reaches of a tributary of the Xiangxi River, which was located in the Three Gorges Area in central China's Hubei Province to the construction of a small run-of-river dam.
They monitored benthic algae, chemical factors, and habitat characteristics both at the upstream and downstream of the dam site from February 2003 to August 2006.
It was found that the overall algal assemblage structure downstream of the dam sites was similar to that of upstream control sites before dam construction and for one year afterwards. However, sites belonging to upstream and downstream reaches became quite different in the algal structure in the 2nd and 3rd years after dam construction.
The results suggest that the impact of dam construction on benthic algal communities took 2 to 3 years to emerge. Based on this finding, the research provided reference for building and managing small dams in mountainous areas and approved the importance of long-term observation of ecosystem.
This research constitutes part of the NSFC (National Natural Science Foundation of China) key program--ecosystem damage caused by dam clusters and its restoration mechanism-a case study of Xiangxi River.
The program was carried out by Field Station for Ecosystem in Xiangxi River that was supported by CAS and the China Three Gorges Project Corporation.
Wu Naicheng from Institute of Hydrobiology, Chinese Academy of Sciences (CAS) published his findings in the Journal of the North American Benghological Society with the title "Changes in benthic algal communities following construction of a run-of-river dam".
Wu and his colleagues examined the responses of the benthic algal communities in downstream reaches of a tributary of the Xiangxi River, which was located in the Three Gorges Area in central China's Hubei Province to the construction of a small run-of-river dam.
They monitored benthic algae, chemical factors, and habitat characteristics both at the upstream and downstream of the dam site from February 2003 to August 2006.
It was found that the overall algal assemblage structure downstream of the dam sites was similar to that of upstream control sites before dam construction and for one year afterwards. However, sites belonging to upstream and downstream reaches became quite different in the algal structure in the 2nd and 3rd years after dam construction.
The results suggest that the impact of dam construction on benthic algal communities took 2 to 3 years to emerge. Based on this finding, the research provided reference for building and managing small dams in mountainous areas and approved the importance of long-term observation of ecosystem.
This research constitutes part of the NSFC (National Natural Science Foundation of China) key program--ecosystem damage caused by dam clusters and its restoration mechanism-a case study of Xiangxi River.
The program was carried out by Field Station for Ecosystem in Xiangxi River that was supported by CAS and the China Three Gorges Project Corporation.
