Truong Kiem N, Vu Ngoc-Anh, Doan Nam X, Bui Canh V, Le Minh-Hoang, Vu Minh T T, Dinh Khuong V
Department of Ecology University of Science, Vietnam National University Hanoi Vietnam.
Cam Ranh Centre for Tropical Marine Research and Aquaculture, Institute of Aquaculture Nha Trang University Nha Trang City Vietnam.
Ecol Evol. 2022 Aug 4;12(8):e9149. doi: 10.1002/ece3.9149. eCollection 2022 Aug.
Marine heatwaves (MHWs) are emerging as a severe stressor in marine ecosystems. Extreme warm sea surface temperatures during MHWs often exceed the optimal thermal range for more than one generation of tropical coastal zooplankton. However, it is relatively unknown whether transgenerational plasticity (TGP) to MHWs may shape the offspring's fitness, particularly in an ecologically relevant context with biotic interactions such as predation stress. We addressed these novel research questions by determining the survival, reproductive success, and grazing rate of the copepod exposed to MHW and fish predator cues (FPC) for two generations (F1 and F2). The experiment was designed in a full orthogonal manner with 4 treatments in F1 and 16 treatments in F2 generation. In both generations, MHW reduced survival, reproductive parameters, and grazing by 10%-62% in MHW, but these parameters increased by 2%-15% with exposure to FPC, particularly at control temperature. F2 reproductive success and grazing rate as indicated by cumulative fecal pellets were reduced by 20%-30% in F1-MHW, but increased by ~2% in F1-FPC. Strikingly, MHW exposure reduced 17%-18% survival, but transgenerational exposure to MHWs fully ameliorated its lethal effect and this transgenerational effect was independent of FPC. Increased survival came with a cost of reduced reproductive success, constrained by reduced grazing. The rapid transgenerational MHW acclimation and its associated costs are likely widespread and crucial mechanisms underlying the resilience of coastal tropical zooplankton to MHWs in tropical coastal marine ecosystems.
海洋热浪正成为海洋生态系统中的一种严重压力源。海洋热浪期间极端温暖的海面温度常常会在超过一代热带沿海浮游动物的最佳热范围内持续较长时间。然而，对于海洋热浪的跨代可塑性（TGP）是否会影响后代的适应性，尤其是在诸如捕食压力等生物相互作用的生态相关背景下，人们相对还不太了解。我们通过确定两代（F1和F2）暴露于海洋热浪和鱼类捕食者线索（FPC）下的桡足类动物的存活率、繁殖成功率和摄食率，来解决这些新的研究问题。实验采用完全正交设计，F1代有4种处理，F2代有16种处理。在两代中，海洋热浪使海洋热浪处理组的存活率、繁殖参数和摄食量降低了10%-62%，但在对照温度下，这些参数在暴露于鱼类捕食者线索时增加了2%-15%。F1代处于海洋热浪环境下时，F2代的繁殖成功率和以累积粪便颗粒表示的摄食率降低了20%-30%，但在F1代处于鱼类捕食者线索环境下时增加了约2%。引人注目的是，暴露于海洋热浪使存活率降低了17%-18%，但跨代暴露于海洋热浪完全缓解了其致死效应，且这种跨代效应与鱼类捕食者线索无关。存活率的提高伴随着繁殖成功率降低的代价，这受到摄食量减少的限制。快速的跨代海洋热浪适应及其相关代价可能广泛存在，并且是热带沿海海洋生态系统中沿海热带浮游动物对海洋热浪恢复力的关键机制。
