School of Engineering and Centre for Water Security and Environmental Sustainability, The University of Newcastle, Callaghan, Australia.
Department of Environmental Sciences, Macquarie University, Sydney, Australia.
Sci Rep. 2020 Aug 6;10(1):13232. doi: 10.1038/s41598-020-70087-x.
Dryland wetlands are resilient ecosystems that can adapt to extreme periodic drought-flood episodes. Climate change projections show increased drought severity in drylands that could compromise wetland resilience and reduce important habitat services. These recognized risks have been difficult to evaluate due to our limited capacity to establish comprehensive relationships between flood-drought episodes and vegetation responses at the relevant spatiotemporal scales. We address this issue by integrating detailed spatiotemporal flood-drought simulations with remotely sensed vegetation responses to water regimes in a dryland wetland known for its highly variable inundation. We show that a combination of drought tolerance and dormancy strategies allow wetland vegetation to recover after droughts and recolonize areas invaded by terrestrial species. However, climate change scenarios show widespread degradation during drought and limited recovery after floods. Importantly, the combination of degradation extent and increase in drought duration is critical for the habitat services wetland systems provide for waterbirds and fish.
旱地湿地是具有弹性的生态系统，能够适应极端的周期性旱涝事件。气候变化预测显示，旱地的干旱程度将会加剧，这可能会影响湿地的弹性，并减少重要的生境服务。由于我们在相关时空尺度上建立洪水-干旱事件与植被响应之间全面关系的能力有限，这些公认的风险一直难以评估。我们通过将详细的时空洪水-干旱模拟与遥感植被对水情的响应相结合，来解决这个问题，该旱地湿地以其高度可变的淹没而闻名。我们表明，耐旱性和休眠策略的结合使湿地植被能够在干旱后恢复，并重新占领被陆地物种入侵的区域。然而，气候变化情景显示，在干旱期间湿地广泛退化，洪水后恢复有限。重要的是，退化程度和干旱持续时间的增加的组合对湿地系统为水鸟和鱼类提供的生境服务至关重要。
