|关键词: 三峡库区 鱼类入侵 蓄水 监测 入侵危害
|Invasive fishes in Three Gorges Reservoir area and preliminary study on effects of fish invasion owing to impoundment
BA Jiawen, CHEN Daqing
Scientific Observing and Experimental Station of Fishery Resources and Environment in the Upper and Middle Reaches of the Yangtze River, Ministry of Agriculture, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, P. R. China
|Three Gorges Reservoir has become a man-made lake ecosystem where there are a lot of ecological niches left vacant or unused. Alien species appear to be successful invaders to fill these empty ecological niches. In recent years, a total of 23 invasive fish species have been found in this reservoir and the upper reaches of Yangtze River, some of which are in the stage of their population outbreak. The main reasons for this are increased nutrient inputs and thus high primary productivity in the initial time of impoundment. They facilitated the invasion of exotic fish species that have the adaptability to a wide range of environmental conditions. With a competitive advantage over indigenous fishes, invasive alien species can replace them. This may be seriously harmful to the fishery resources and aquatic ecological systems in Three Gorges Reservoir. Evidently, more attention should be paid to affects and other related issues caused by the invasive alien fish. The following measures can be urgently taken:the establishment of the early warning and prevention systems of invasive alien fish species, the assessment on the potential affects of the introduction of alien cultured fishes, and thorough investigations of mechanisms of exotic fish fishes as the successful invaders adapted for the reservoir environmental conditions.
|Key words: Three Gorges Reservoir area fish invasion impoundment monitor invasive harm