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  • Bottom substrate attributes relative to bedform morphology of spawning site of Chinese sturgeon...

    Abstract: Characteristics of bottom substrates have caused wide concernas to their importance for sturgeon spawning ground
    requirements. Substrate requirements for spawning of Chinese sturgeon Acipenser sinensis have not yet been well studied because of the difficulties in investigating on a large and fast flowing river such as the Yangtze River. During 2007 and 2008, the underwater video surveys on the present spawning ground of A. sinensis were successfully conducted. Two kinds of substrates were documented: one stable infrastructure consisting of large boulders and cobbles mixed with pebbles and gravels, the other comprise sediments in transportation, especially coarse and fine sands. The large boulders (size range 20–50 cm), cobbles and pebbles (size range 10–20 cm), pebbles or gravels are estimated to account for 50, 30, 20% of the available substrates of the infrastructure on spawning ground according to our underwater video survey points, respectively. The transporting sands can be observed in most area, while the river sand embedded or covered the large structural compounds just occur in certain area and the substrate where spawning occurs annually and occasionally were similarly "clean" of fine sediment...


    附件下載:H.Du, Q.W.Wei, H.Zhang, et al. Bottom substrate attributes relative to bedform morphology of spawning site of Chinese sturgeon Acipenser sinensis below the Gezhouba dam. J.Appl. Ichthyol. 2011, 27: 257-262. pdf
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