Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, HI 96744, United States.
Crustal Geophysics and Geochemistry Science Center, U.S. Geological Survey, Bldg 20, MS 964D, Denver Federal Center, Denver, CO 80225, United States.
Environ Pollut. 2016 Jun;213:240-253. doi: 10.1016/j.envpol.2016.01.086. Epub 2016 Feb 21.
Metal pollutants in marine systems are broadly acknowledged as deleterious: however, very little data exist for tropical scleractinian corals. We address this gap by investigating how life-history stage, season and thermal stress influence the toxicity of copper (Cu) and lead (Pb) in the coral Pocillopora damicornis. Our results show that under ambient temperature, adults and larvae appear to tolerate exposure to unusually high levels of copper (96 h-LC50 ranging from 167 to 251 μg Cu L(-1)) and lead (from 477 to 742 μg Pb L(-1)). Our work also highlights that warmer conditions (seasonal and experimentally manipulated) reduce the tolerance of adults and larvae to Cu toxicity. Despite a similar trend observed for the response of larvae to Pb toxicity to experimentally induced increase in temperature, surprisingly adults were more resistant in warmer condition to Pb toxicity. In the summer adults were less resistant to Cu toxicity (96 h-LC50 = 175 μg L(-1)) than in the winter (251 μg L(-1)). An opposite trend was observed for the Pb toxicity on adults between summer and winter (96 h-LC50 of 742 vs 471 μg L(-1), respectively). Larvae displayed a slightly higher sensitivity to Cu and Pb than adults. An experimentally induced 3 °C increase in temperature above ambient decreased larval resistance to Cu and Pb toxicity by 23-30% (96 h-LC50 of 167 vs 129 μg Cu L(-1) and 681 vs 462 μg Pb L(-1)). Our data support the paradigm that upward excursions in temperature influence physiological processes in corals that play key roles in regulating metal toxicity. These influences are more pronounced in larva versus adult corals. These findings are important when contextualized climate change-driven warming in the oceans and highlight that predictions of ecological outcomes to metal pollutants will be improved by considering environmental context and the life stages of organism under study.
然而，关于热带石珊瑚的数据却很少。我们通过研究生活史阶段、季节和热应激如何影响珊瑚 P. damicornis 对铜 (Cu) 和铅 (Pb) 的毒性来填补这一空白。我们的结果表明，在环境温度下，成体和幼虫似乎能够耐受异常高浓度的铜（96 h-LC50 范围为 167 至 251μg Cu L(-1)) 和铅（477 至 742μg Pb L(-1))。我们的工作还强调，较暖的条件（季节性和实验性操纵）降低了成体和幼虫对铜毒性的耐受性。尽管幼虫对 Pb 毒性的反应也观察到类似的趋势，但在较暖的条件下，成体对 Pb 毒性的抵抗力更强。在夏季，成体对 Cu 毒性的抵抗力低于冬季（96 h-LC50 为 175μg L(-1))。在夏季和冬季，成体对 Pb 毒性的反应则相反（96 h-LC50 分别为 742 和 471μg L(-1))。幼虫对 Cu 和 Pb 的敏感性略高于成体。在环境温度基础上升高 3°C 会降低幼虫对 Cu 和 Pb 毒性的抵抗力，降低幅度为 23-30%（96 h-LC50 分别为 167 对 129μg Cu L(-1)和 681 对 462μg Pb L(-1))。我们的数据支持这样一种观点，即温度的上升会影响珊瑚的生理过程，这些过程在调节金属毒性方面起着关键作用。这些影响在幼虫和成体珊瑚之间更为明显。当考虑到海洋中气候变化驱动的变暖以及强调到对金属污染物的生态后果的预测将通过考虑环境背景和所研究生物的生活阶段而得到改善时，这些发现非常重要。
