Vertical distribution of marine invertebrate larvae in response to thermal stratification in the laboratory

We investigated the effect of the presence of an experimentally generated thermocline on the vertical distribution of larval Strongylocentrotus droebachiensis, Asterias rubens and Argopecten irradians. Vertical distributions were recorded over 90 min in rectangular plexiglass thermocline chambers designed to regulate the temperature of a central observation compartment to the desired values. The temperature in the bottom water layer (B) and the temperature difference between layers (ΔT) were manipulated in an orthogonal design. We used, for S. droebachiensis: 4 levels of ΔT (0, 3, 6 and 12 °C) and 3 levels of B (3, 6 and 9 °C); for A. rubens: 3 levels ΔT (0, 6 and 12 °C) and 2 levels of B (6 and 12 °C); and for A. irradians: 3 levels of ΔT (0, 5 and 11 °C) and 2 levels of B (5 and 11 °C). The difference in temperature between water layers did not affect the vertical distribution of echinoderms consistently, while the distribution of A. irradians was limited to the bottom layer when any ...

本研究探究了实验构建的温跃层（thermocline）对强棘紫海胆（Strongylocentrotus droebachiensis）、多棘海盘车（Asterias rubens）以及海湾扇贝（Argopecten irradians）幼体垂直分布的影响。实验在可将中央观测舱温度调控至预设值的矩形有机玻璃（plexiglass）温跃层舱中开展，连续90分钟记录受试生物的垂直分布情况。本实验采用正交设计（orthogonal design），对底层水层温度（记为B）与水层间温差（记为ΔT）进行变量调控。针对强棘紫海胆，设置了4个ΔT梯度（0、3、6和12 ℃）与3个B梯度（3、6和9 ℃）；针对多棘海盘车，设置了3个ΔT梯度（0、6和12 ℃）与2个B梯度（6和12 ℃）；针对海湾扇贝，设置了3个ΔT梯度（0、5和11 ℃）与2个B梯度（5和11 ℃）。水层间温差并未对棘皮动物（echinoderms）的垂直分布产生一致性影响，而海湾扇贝的分布在任意...