Collaborative Research: ORCC: Saltwater Rising: Understanding how sea level rise affects coastal amphibians

由于海平面上升和风暴潮加剧，气候变化正在增加沿海淡水生境的盐分。无尾两栖动物（青蛙和蟾蜍）在湿地生态系统中起着关键作用，被认为不耐盐水，但最近的合成表明比以前认为的更耐盐。该项目提高了我们对占据两个海平面上升前沿（海湾和大西洋海岸）沿海栖息地的无尾两栖类物种的耐盐极限的理解。该项目采用实验方法，调查多个盐度，物种，生命阶段和生物组织水平，提供数据，可以指导沿海管理人员和从业人员提高沿海弹性和防止生物多样性丧失。具体而言，该研究将确定不同物种因盐胁迫而导致的特定生命阶段死亡率，以预测脆弱的生命阶段和繁殖时间。这项研究将确定物种的相关性和生态特征是否可以预测盐度的脆弱性和特征的程度，在一个生命阶段的影响，在整个生命阶段级联。最后，本研究旨在了解盐水如何影响两栖动物的生理跨物种和生命阶段，重点是膜渗透性，激素和细胞过程。总之，这项研究将产生跨越生命阶段和物种的不同生理，生活史，系统发育和基因组数据集，以确定占据沿海栖息地的无尾两栖动物物种的耐盐性，其目标是为保护行动提供信息并预测气候变化的影响。该项目还将教育学生和公众关于各种主题，如保护和生理学。气候变化导致的海平面上升正在加剧沿海生境的盐碱化。美国海岸沿着海平面预计将在未来70年内上升50至100厘米，东部和海湾海岸将面临更严重的影响。无尾两栖动物，或青蛙和蟾蜍，预计将受到严重影响的盐度增加，因为他们被认为在很大程度上不容忍盐水。然而，两栖动物的耐盐性比通常认为的更多变，在预测海水淹没对沿海社区的影响时存在不确定性。为了解决这些差距，这项研究将集中在10个无尾类物种与已知的人口在五英里的海岸线附近的休斯顿，得克萨斯州和萨佩洛岛，格鲁吉亚。这些地点是双重海平面上升前沿，在中度海平面上升的情况下，预计到2050年，低海拔海岸线和淡水湿地将被淹没。该项目将使用比较的方法来研究生活史特征和进化史如何影响在较高盐度下的阶段特异性生存，慢性盐水暴露如何影响长期生长，发育和健康，以及对盐水暴露的生理反应。这项研究将为以下问题提供信息：复杂的生命周期如何影响新环境中的持久性，生理机制如何促进盐水耐受性，以及慢性与急性暴露如何影响生存和持久性。此外，该研究将为预测不同的沿海物种将如何应对海平面上升推动海水进一步上游和内陆，这可以指导沿海管理人员和从业人员，以提高沿海弹性和防止生物多样性的损失提供基线。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Climate change is increasing the amount of salt of coastal freshwater habitats, driven by sea-level rise and intensified storm surges. Anurans (frogs and toads) play a pivotal role in wetland ecosystems and are presumed to be intolerant of saltwater, but recent syntheses indicate more salt tolerance than previously thought. This project improves our understanding of the limits of salt tolerance in anuran species occupying coastal habitats on two sea level rise fronts (Gulf and Atlantic coasts). The project uses an experimental approach that investigates multiple salinities, species, life stages, and levels of biological organization, providing data that can guide coastal managers and practitioners in improving coastal resilience and preventing biodiversity loss. Specifically, the study will identify life stage-specific mortality from salt stress across species to predict vulnerable life stages and breeding times. This research will determine whether species relatedness and ecological traits can predict salinity vulnerability and characterize the extent that the effects of saltwater at one life stage cascade across life stages. Finally, this study aims to understand how saltwater affects amphibian physiology across species and life stages, focusing on membrane permeability, hormones, and cellular processes. In summary, this research will produce diverse physiological, life history, phylogenetic, and genomic datasets that span across life stages and species to determine the salinity tolerance of anuran species that occupy coastal habitats with the goal of informing conservation actions and predicting climate change impacts. The project will also educate students and the public on various topics such as conservation and physiology. Climate change-driven sea level rise is increasing salinization of coastal habitats. Sea levels along the United States coastlines are predicted to rise between 50 and 100 cm in the next 70 years, with the east and gulf coasts facing intensified impacts. Anurans, or frogs and toads, are expected to be severely affected by salinity increases, as they are considered largely saltwater intolerant. However, salinity tolerance among amphibians is more variable than commonly considered, leaving uncertainty in the predictions of seawater inundation effects on coastal communities. To address these gaps, this research will focus on 10 anuran species with known populations within five miles of coastlines near Houston, Texas and Sapelo Island, Georgia. These locations are dual sea level rise fronts with low-elevation coastlines and freshwater wetlands expected to be inundated by the year 2050 under moderate sea level rise scenarios. The project will use a comparative approach to investigate how life history traits and evolutionary history affect stage-specific survival in higher salinities, how chronic saltwater exposure affects long-term growth, development, and fitness, and the physiological responses to saltwater exposure. This research will inform questions on how complex life cycles affect persistence in novel environments, how physiological mechanisms facilitate saltwater tolerance, and how chronic versus acute exposure affect survival and persistence. Additionally, this research will provide baselines for predicting how different coastal species will fare as sea level rise pushes saltwater further upriver and inland, which can guide coastal managers and practitioners to improve coastal resiliency and prevent biodiversity losses.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.