漂流性鱼卵的孵化特性及水动力需求研究进展

鱼卵运动规律研究是鱼类产卵场位置推算、水库生态调度和鱼类资源保护的基础。对于产漂流性卵鱼类，当流水环境不足以维持鱼卵漂流时，鱼卵便下沉死亡而无法孵化成幼鱼。通过对照中国内陆鱼类名录，查阅国内重要流域及地方鱼类志中有关产漂流性卵鱼类的繁殖条件，梳理了典型鱼类的产卵水温、产卵时间和孵化时长等相关信息。针对现有鱼类志中对于鱼卵基本物理性质及鱼卵孵化所需水动力条件信息缺失的情况，补充查阅了国内外相关文献，归纳总结了漂流性鱼卵安全漂流的水动力条件。一种观点认为鱼卵在水体中是否能安全漂流取决于水体的流速，另一种观点认为控制漂流性鱼卵悬浮或下沉的关键参数是湍流状态或剪切速度，而不是水流的线速度，现有漂流性鱼卵孵化的关键水动力条件和阈值尚有争议，仍需加强鱼卵运动规律的相关试验研究。目前国内外对鱼卵的漂流输移研究方法和手段，主要采用野外监测、室内实验和模型模拟。已有研究大多只是针对鱼卵运动规律本身进行单一试验或模型验证，如何通过水库调度最大程度保障漂流性鱼卵的漂流孵化条件是未来鱼类保护的重要方向。

Review of Research on the Hydrodynamic Requirements for Sustained Drifting and Hatching of Buoyant Fish Eggs

Figure out the law of egg movement is the basis of calculating the position of spawning ground, reservoir ecological regulation and fish resource protection. Especially for fishes with semi-buoyant eggs, when the hydrodynamic condition is not enough to sustain the drifting of eggs, the eggs will sink and perish. In this paper, based on the list of inland fish in China, the breeding conditions of fishes with semi-buoyant eggs were consulted by referring to ichthyology books of important river basins in China. Relevant information such as the spawning water temperature, spawning month and hatching duration of typical fishes with semi-buoyant eggs were listed. In available ichthyology books, there are few records on the basic physical properties of fish eggs and the hydrodynamic conditions required for safe drifting of fish eggs. Thus, we consulted relevant literatures at home and abroad, and summarized the advances in the hydrodynamic conditions for safe drifting of fish eggs. One view holds that the drifting of semi-buoyant eggs in water depends on the minimum flow velocity requirement to keep semi-buoyant eggs and larvae in the drift; the other holds that the key parameters controlling floating or sinking of semi-buoyant eggs are turbulence or shear velocity, rather than the linear velocity of the water. The key hydrodynamic conditions and thresholds of semi-buoyant eggs are still controversial, and the motion law of semi-buoyant eggs still needs further study. On this basis, this paper summarizes the current research methods of the motion law of semi-buoyant eggs in water at home and abroad, mainly through field observation, laboratory experiment and model simulation. These researches greatly promote the understanding of fish eggs movement mechanism, but most studies only focused on a single problem of eggs motion through the way of experiment or model. How to create hydrological condition needed for the eggs hatch through ecological operation of water conservancy projects, and put forward multidimensional control method of ecological effects of water conservancy projects are key research fields in the future.