不同底播时间和苗种规格的魁蚶潜沙率差异性分析

【目的】了解魁蚶(Scapharca broughtonii)生物学特性,为更好地开展魁蚶底播增殖工作提供数据支持。【方法】采用围格实验生态学方法研究4种规格魁蚶在4个不同底播时间下的潜沙率差异性。【结果】不同底播时间下,在实验开始前24h内,1cm、1.5cm和2cm组魁蚶潜沙率差异不显著,但均高于2.5cm组;在底播36h后4种规格魁蚶潜沙率无显著差异。底播时间选在9:00、13:00和17:00时,同规格的魁蚶潜沙率无明显差异,均高于在21:00时底播。【结论】在底播时应选取潜沙速率快且潜沙率较为稳定的规格作为埋栖型贝类的底播规格,根据实验结果建议选择2cm魁蚶做为底播苗种;底播时间应根据当地海区潮汐情况确定,选择平流期开展底播,最佳底播时间应选取17:00,尽量避开夜间底播。

The Analysis of Burrowing Rate with Different Sizes and Different Bottom Sowing Time of Scapharca broughtonii

Objective] In order to study the biological character of Scapharca broughtonii,the experiments were carried out.The results provided basic data for promoting steady and healthy development of the multiplication and cultivation of S.broughtonii.Methods] The difference of burrowing rate with different sizes in Scapharca broughtonii under different bottom sowing time was analyzed in this article.Results] The results suggested that the burrowing rate of 1 cm,1.5 cm and 2 cm was higher than 2.5 cm under different bottom sowing time.The burrowing percentage of 1 cm,1.5 cm and 2 cm experimental groups had no significant differences at all conditions before the starting of the experiment in 24 h,which was higher than the burrowing percentage of 2.5 cm experimental group.The burrowing percentage had no remarkable differences at all sizes of S.broughtonii after 36 h in the experiment.The burrowing rates of S.broughtonii which were burrowed at 9:00,13:00 and 17:00 were higher than 21:00,but were insignificantly different among them.Conclusion] The size whose burrowing rate was fast and stable should be chosen as the gauge of burrowing rate.According the results,we suggested 2 cm as a suitable specification to stock enhancement.17:00 would be the best time with advection stage for stock enhancement,which also should avoid night time.