Can Salinity-Induced Mortality Explain Larval Vertical Distribution With Respect to a Halocline?
Can Salinity-Induced Mortality Explain Larval Vertical Distribution With Respect to a Halocline?
复制标题
盐度引起的死亡率可以解释幼虫相对于盐跃层的垂直分布吗？
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
A. Metaxas
中科院分区：
文献类型：
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作者：
J. Sameoto;A. Metaxas
对于在大西洋加拿大共存的两种棘皮动物的幼虫(海星Asterias Rubens的双鳍幼虫和海胆Strongyloctrotus droebachiensis的4臂和6臂棘皮动物)，我们在实验室实验中考察了短期和长期暴露于盐度(从18到35)对幼虫存活概率的影响。我们还将幼虫对实验室产生的尖锐盐跃层的垂直分布与水柱中不同层的盐度下的存活概率进行了关联。对于物种和发育阶段，存活概率都随着盐度的降低而降低，盐度范围24-27是幼虫耐受性的临界阈值。幼虫跨过盐跃层进入上层水层的比例与幼虫在该层盐度下的存活概率之间的关系对两种鱼类都是显著的。有趣的是，这种反应的形状是物种特异性的，而不是阶段特异性的。我们的发现表明，幼虫避开低盐度水层可能是一种适应行为，可以提高存活率，并间接影响幼虫的分布。
For the larvae of two echinoderm species that coexist in Atlantic Canada (bipinnaria of the sea star Asterias rubens and 4- and 6-arm echinoplutei of the sea urchin Strongylocentrotus droebachiensis), we examined the effect of short- and long-term exposure to salinity (ranging from 18 to 35) on the probability of larval survival in laboratory experiments. We also related larval vertical distributions in response to sharp haloclines generated in the laboratory to survival probability in the salinity of different layers in the water column. For both species and developmental stages, survival probability decreased with decreasing salinity, and a salinity range of 24–27 emerged as the critical threshold for larval tolerance. The relationship between the proportion of larvae that crossed a halocline into the top water layer and the survival probability of larvae in the salinity of that layer was significant for both species. Interestingly, the shape of this response was species-specific but not stage-specific for S. droebachiensis. Our findings suggest that larval avoidance of low-salinity water layers may be an adaptive behavior that increases survival and indirectly influences larval distribution.