The Effect Of Huangjin Gorge Hydropower Station Construction On The Fish Resources In The Xixiang Aquatic Conservation Area Of Hanjiang River

The Hanjiang River that originated in south of Qinling Mountains, got through Shaanxi province and Hubei province, imported to Yangtze River in Wuhan finally is the largest tributary of the Yangtze River. Three sections that upper reaches was above Danjiang estuary, middle reaches was from Danjiang estuary to Zhongxiang and lower reaches was from Zhongxiang to Hankou river were divided through entire main Hangjiang river. Hanjiang River have abundant water resources, especially the slope of upper reach is steep and had a big drop. Since1950, seven cascade hydropower stations were planned to develop in the upper reaches of Hanjiang River. Till now,4hydropower stations such as Shiquan, Ankang, Xihe and Shuhe had been put into operation, and preliminary design of Huangjin Gorge hydropower station which was the first cascade in the upper reaches of Hanjiang River had been carried out. As planned, Huangjin Gorge hydropower station Dam was located in the upper reach of Hanjiang, which is in the experimental area of Xixiang national aquatic germplasm resources conservation area.Xixiang national aquatic germplasm resources conservation area whose total area was5116km2was located in the Xixiang town, Hanzhong city of Shanxi province. Its main protected fish were Pelteobagrus fulvidraco, Schizothorax prenanti and Cyprinus carpio.In order to reduce the effect of station construction on the fish resources in the Xixiang aquatic germplasm resources conservation area of Hanjiang River as far as possible, based on consulting the relevant historical data,the survey of fish resources and its food organism in the conservation area was conducted by sampling and field visits etc. methods in Aug,2010and Sep-Oct,2011. There were55kinds,1645fish founed, belonging to4orders,10families, dominated by Cyprinidae (34species). It belongs to the7fauna complex in the fauna composition. Medium and small-sized fish get the dominant position in the species and quantities.2most important fish species and15important fish species were determined by index of relative importance that in the fish community. The eigenvalue of the fish communities biodiversity can be calculated that the richness index is2.2719, the diversity index is1.4098and the evenness index is0.6226. This is showed that the reach’s fish community diversity is low and the community structure is not stable. There is phytoplankton (7phylum,61genera), zooplankton (4class,33genera) and benthic animals (19species) and aquatic plant (39species) in the food organisms.According to the research results on the fish resources in conservation area combined Huangjin Gorge hydropower station development programs, it could be predicted that the effect of construction projects involved:(1)Huangjin Gorge hydropower station construction would break the integrality of conservation area and the migration channels and gene communication of fish in upper and lower river were blocked. Thus it would impact the genetic diversity of fish in conservation area.(2)the effect on main protected fish in conservation area (3) the effect on population structure of fish resource in conservation area (4) the effect on juvenile fish resource in conservation area (5) the effect on "three grounds and one channels" of fish in conservation area.As the basis for the characteristic of fish community in conservation area and the effect calculation of Huangjin Gorge hydropower station construction on the fish resources in the Xixiang aquatic germplasm resources conservation area of Hanjiang River, the measures of building fish passage facilities, manual restoring, others relevance measures and adjusting conservation area etc. correspondingly were proposed.