【摘要】 鱼类产卵场是鱼类栖息地中重要且敏感的场所。加权可利用栖息地面积被广泛用来判断产卵场适宜性的依据,但是鲜有人探讨产卵场生境的多样性变化。故本文借用景观生态学中生境异质性的概念,提出鱼类产卵场微生境异质性,将不同类型的水深、流速划分为斑块,采用Shannon多样性指数对产卵场的微生境异质性进行分析。以大渡河金川坝址下游的复兴村产卵场为例,研究了流量变化造成的产卵场水深和流速变化,讨论了水深和流速的变化对鱼类产卵场微生境异质性的影响,并通过对比不同流量下多样性指数的大小和变化趋势,得出产卵场在流量为156 m3/s时,基于水深—流速多样性指数得出的微生境异质性为最佳。更多还原

【Abstract】 Spawning ground, the reproduction place of fish, is an important and susceptive habitat. Weighted usable area has been widely used in evaluating the suitability of spawning ground. However, previous studies on the diversity of spawning ground were very rare. To describe the impact caused by the change in river discharge, a concept of microhabitat heterogeneity is presented in this paper based on the habitat heterogeneity in landscape ecology. Water depth and velocity patches were chosen as two major factors in evaluating the heterogeneous level of microhabitat and the Shannon diversity index was adopted as a mathematic principle. A case study of the Fuxing village downstream of the Jinchuan dam on the Dadu River was taken to identify the relationship of microhabitat heterogeneity versus river discharge. According to the results, the optimum flow depth-velocity heterogeneity occurs at the discharge of 156 m3/s.更多还原