The larvae of congeneric gastropods showed differential responses to the combined effects of ocean acidification, temperature and salinity

The tolerance and physiological responses of the larvae of two congeneric gastropods, the intertidal Nassarius festivus and subtidal Nassarius conoidalis, to the combined effects of ocean acidification (PCO2 at 380, 950, 1250 ppm), temperature (15, 30 degrees C) and salinity (10, 30 psu) were compared. Results of three-way ANOVA on cumulative mortality after 72-h exposure showed significant interactive effects in which mortality increased with pCO(2) and temperature, but reduced at higher salinity for both species, with higher mortality being obtained for N. conoidalis. Similarly, respiration rate of the larvae increased with temperature and pCO(2) level for both species, with a larger percentage increase for N. conoidalis. Larval swimming speed increased with temperature and salinity for both species whereas higher pCO(2) reduced swimming speed in N. conoidalis but not N. festivus. The present findings indicated that subtidal congeneric species are more sensitive than their intertidal counterparts to the combined effects of these stressors. (c) 2014 Elsevier Ltd. All rights reserved.

本研究对比了两种同属腹足类（gastropods）幼虫对海洋酸化（ocean acidification）、温度（15、30℃）及盐度（10、30 psu）复合胁迫的耐受性与生理响应，供试物种分别为潮间带织纹螺（Nassarius festivus）与潮下带织纹螺（Nassarius conoidalis），其中海洋酸化设置的PCO₂水平分别为380、950、1250 ppm。对72小时暴露后的累积死亡率开展三因素方差分析（three-way ANOVA），结果显示存在显著交互效应：两种螺的死亡率均随pCO₂与温度升高而上升，随盐度升高而降低，且N. conoidalis的死亡率更高。同样地，两种螺的幼虫呼吸速率均随温度与pCO₂水平升高而上升，其中N. conoidalis的呼吸速率增幅更为显著。两种螺的幼虫游泳速度均随温度与盐度升高而提升，但高pCO₂仅会降低N. conoidalis的游泳速度，对N. festivus无明显影响。本研究结果表明，相较于潮间带近缘物种，潮下带同属腹足类对这类胁迫因子的复合效应更为敏感。©2014 Elsevier Ltd. 保留所有权利。