Programa Magister en Ecología de Sistemas Acuáticos, Universidad de Antofagasta, Av. Angamos 601, P.O. Box 170, Antofagasta, Chile; Instituto de Ciencias Naturales "Alexander von Humboldt", Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Av. Angamos 601, P.O. Box 170, Antofagasta, Chile.
Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile; Laboratorio de Ecología y Conducta de la Ontogenia Temprana (LECOT), Coquimbo, Chile.
Int J Parasitol. 2019 Jan;49(1):49-61. doi: 10.1016/j.ijpara.2018.08.006. Epub 2018 Nov 15.
Ocean warming and acidification are general consequences of rising atmospheric CO concentrations. In addition to future predictions, highly productive systems such as the Humboldt Current System are characterized by important variations in both temperature and pCO level, but how these physical-chemical ocean changes might influence the transmission and survival of parasites has not been assessed. This study experimentally evaluated the effects of temperature (14, 18 and 25 °C) and the combined effects of temperature (∼15 and 20 °C) and pCO level (∼500 and 1400 microatmospheres (µatm) on the emergence and survival of two species of marine trematodes-Echinostomatidae gen. sp. and Philophthalmidae gen. sp.-both of which infect the intertidal snail Echinolittorina peruviana. Snails were collected from intertidal rocky pools in a year-round upwelling area of the northern Humboldt Current System (23°S). Two experiments assessed parasite emergence and survival by simulating emersion-immersion tidal cycles. To assess parasite survival, 2 h old cercariae (on average) were taken from a pool of infected snails incubated at 20-25 °C, and their mortality was recorded every 6 h until all the cercariae were dead. For both species, a trade-off between high emergence and low survival of cercariae was observed in the high temperature treatment. Species-specific responses to the combination of temperature and pCO levels were also observed: the emergence of Echinostomatidae cercariae was highest at 20 °C regardless of the pCO levels. By contrast, the emergence of Philophthalmidae cercariae was highest at elevated pCO (15 and 20 °C), suggesting that CO may react synergistically with temperature, increasing transmission success of this parasite in coastal ecosystems of the Humboldt Current System where water temperature and pH are expected to decrease. In conclusion, our results suggest that integrating temperature-pCO interactions in parasite studies is essential for understanding the consequence of climate change in future marine ecosystem health.
海洋变暖与酸化是大气 CO2 浓度升高的普遍后果。除了未来的预测，像洪堡海流系统这样的高生产力系统的温度和 pCO2 水平也存在重要变化，但这些物理化学海洋变化如何影响寄生虫的传播和生存尚未得到评估。本研究通过实验评估了温度（14、18 和 25°C）以及温度（约 15 和 20°C）和 pCO2 水平（约 500 和 1400 微大气压（µatm））联合效应对两种海洋吸虫-Echinostomatidae 属和 Philophthalmidae 属的影响，这两种吸虫均感染潮间带贻贝 Echinolittorina peruviana。贻贝从洪堡海流系统北部全年上升流区的潮间带岩石池采集。两个实验通过模拟出露-浸没潮汐周期来评估寄生虫的出现和生存。为了评估寄生虫的存活率，从在 20-25°C 下孵育的感染贻贝池中取出平均 2 小时龄的尾蚴，并每 6 小时记录一次死亡率，直到所有尾蚴死亡。对于这两个物种，在高温处理中观察到尾蚴高出现率和低存活率之间的权衡。还观察到温度和 pCO2 水平联合效应对两种物种的特异性反应：Echinostomatidae 尾蚴的出现率在 20°C 时最高，无论 pCO2 水平如何。相比之下，Philophthalmidae 尾蚴的出现率在高 pCO2（15 和 20°C）时最高，这表明 CO 可能与温度协同作用，增加了这种寄生虫在洪堡海流系统沿海生态系统中的传播成功率，预计这些生态系统中的水温和 pH 值将会下降。总之，我们的结果表明，在寄生虫研究中整合温度-pCO2 相互作用对于理解未来海洋生态系统健康中气候变化的后果至关重要。
