Downstream dispersal of zebra mussels (Dreissena polymorpha) under different flow conditions in a coupled lake-stream ecosystem
Downstream dispersal of zebra mussels (Dreissena polymorpha) under different flow conditions in a coupled lake-stream ecosystem
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湖-溪耦合生态系统中不同水流条件下斑马贻贝（Dreissena polymorpha）的下游扩散
DOI：
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发表时间：
2018
影响因子：
2.9
通讯作者：
Daniel P. Quigley
中科院分区：
文献类型：
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作者：
C. J. Churchill;Daniel P. Quigley
在入侵的湖泊-河流生态系统中，河流流速和体积流量会影响斑马贻贝（斑马贻贝）等水生入侵物种的扩散、建立和传播。斑马贻贝是一种浮游幼体，从源头种群迅速向下游扩散。在美国德克萨斯州北部的一个湖-溪耦合生态系统中，研究了不同体积流量（或流量）条件下斑马贻贝的浓度、扩散和身体状况。河流环境中的浮游生物密度与上游淡水源种群的种群动态密切相关。在下游28公里的研究范围内，观察到大蠊密度呈指数级下降。源水库放水量的增加增加了威利格通量和扩散势，随之增加了威利格通量，缩短了传递时间。然而，在高流量事件期间，通过大坝释放闸门和河流湍流增加会对飞虱的身体状况产生负面影响，飞虱的身体状况从源种群到下游最远的地点普遍下降，在高流量期间飞虱的身体状况较低。因此，由于湍流引起的死亡率增加，流量增加似乎降低了活菌的比例。如果流量和繁殖压力足够，或者如果临时栖息地适合建立溪流种群，则可以在遥远的下游水库中定居。
Dispersal, establishment, and spread of aquatic invasive species such as the zebra mussel (Dreissena polymorpha) can be influenced by riverine velocities and volumetric flows in invaded lake-stream ecosystems. Zebra mussels, which have a planktonic larval form (veliger), disperse rapidly downstream from a source population. Concentrations, dispersal, and body conditions of zebra mussel veligers were studied under different volumetric flow, or discharge, conditions in a coupled lake-stream ecosystem in northern Texas, USA. Veliger densities in lotic environments were strongly related to population dynamics in upstream lentic source populations. A strong exponential decrease in veliger density was observed through a 28-km downstream study reach. Increased water releases from the source reservoir increased veliger flux and dispersal potential, concomitantly increasing veliger flux and decreasing transit time. However, passage through release gates in the dam and increased turbulence in the river during high-discharge events could negatively affect body condition of veligers, and veliger body condition generally decreased from the source population to the farthest downstream site and was lower for veligers during periods of high discharge. Thus increased discharge appears to reduce the proportion of viable veligers because of increased turbulence-induced mortality. Colonization of distant downstream reservoirs can occur if discharge and propagule pressure are sufficient or if interim habitats are suitable for establishment of in-stream populations.