罗梭江鱼类替代生境量化评价

Quantitative evaluation of fish alternative habitats in the Luosuo River

针对罗梭江替代生境适宜度及影响因素尚缺乏定量分析的问题,选取澜沧江干流特有经济鱼类中国结鱼(Tor sinensis)为目标物种,基于河流内流量增加法(IFIM),结合二维水动力模型和鱼类栖息地适宜性曲线,建立了罗梭江典型鱼类的栖息地评价模型,分析了替代生境适宜度及其影响因子。结果表明:罗梭江作为澜沧江最大支流,能为中国结鱼提供良好产卵场,产卵场在丰水期(7—9月)数量和质量较优,高质量产卵场主要分布于河流蜿蜒处;罗梭江不适宜成鱼全年栖息,尤其在枯水期(2—4月),成鱼产卵及育肥适宜度最差。在罗梭江替代生境后期管理中,建议优先加强对河流弯道处的生境保护及捕捞管理,同时重视其关联干流的生态保护。

In view of the lack of quantitative analysis on the alternative habitatsuitability and influencing factors in the Luosuo River,Tor sinensis,a unique economic fish in the main stream of the Lancang River,was selected as the target species,and the habitat evaluation model of typical fish in theLuosuoRiver was established based on the intra-river flow increasing method(IFIM),two-dimensional hydrodynamic model and fish habitat suitability curve.The alternative habitat suitability and its influencing factors were analyzed.The results show that the Luosuo River,as the largest tributary of Langcang River,can provide a good spawning ground for Tor sinensis.The number and quality of spawning ground are better in wet season(July to September),and high-quality spawning ground is mainly distributed in the meandering part of the river.The tributaries of the Luosuo River are not suitable for adult fish to inhabit all year round,especially in the dry season(February to April),and the suitability of adult fish for spawning and fattening is the worst in this period.In the later management of the alternative habitat of the Luosuo River,it is recommended to give priority to strengthening the habitat protection and fishing management at the river bend,and pay attention to the ecological protection of its associated mainstreamat the same time.