Abstract Geographically isolated wetlands (GIWs) provide a portfolio of ecosystem services in low-gradient, Coastal Plain landscapes. Understanding how GIWs influence downstream waters is becoming increasingly important for conservation and management of these unique and important wetland ecosystems. Climatic conditions are known to be key drivers of water budgets at both individual GIW and landscape scales; however differences in hydrologic response across these scales may provide insights into how GIWs influence downstream waters. In this study, we use a combination of GIW water level, gaged streamflow, and climatic data to explore linkages between seasonal climatic drivers, GIW hydrology, and downstream discharges within the Coastal Plain of the Chesapeake Bay watershed. We first examine water balance components at the larger watershed scale, where climatic drivers result in an energy-limited wet season from December to May and a water-limited dry season from June to November. We compare long-term water levels of three GIWs with downstream discharges. GIW water level and downstream discharges are correlated at seasonal (R2: 0.52–0.60) and daily (R2: 0.52–0.76) time steps. However, during dry seasons, GIW water level receded at a faster rate than downstream discharges, highlighting the influence of evapotranspiration on surface and shallow subsurface water storage. Conversely during wet seasons, GIW water level receded slower than downstream discharges, highlighting a potential period for surface water connectivity between GIWs and downstream discharges. Cumulatively, these findings quantify the impact of seasonal climatic drivers on GIW hydrology and connectivity to downstream waters.

中文翻译：

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低梯度沿海平原景观中地理上孤立的湿地水文的季节性驱动因素

摘要地理隔离湿地 (GIW) 在低梯度沿海平原景观中提供了一系列生态系统服务。了解 GIW 如何影响下游水域对于保护和管理这些独特而重要的湿地生态系统变得越来越重要。众所周知，气候条件是单个 GIW 和景观尺度上水预算的关键驱动因素；然而，这些尺度上水文响应的差异可能有助于深入了解 GIW 如何影响下游水域。在本研究中，我们结合使用 GIW 水位、测量的流量和气候数据来探索季节性气候驱动因素、GIW 水文和切萨皮克湾流域沿海平原下游排放之间的联系。我们首先在更大的流域尺度上检查水平衡分量，气候驱动因素导致 12 月至 5 月的能源有限的雨季和 6 月至 11 月的水资源有限的旱季。我们将三个 GIW 的长期水位与下游排放进行了比较。GIW 水位和下游排放在季节性 (R2: 0.52–0.60) 和每日 (R2: 0.52–0.76) 时间步长上相关。然而，在旱季，GIW 水位的下降速度快于下游排放，突出了蒸散对地表和浅层地下蓄水量的影响。相反，在雨季，GIW 水位的下降速度慢于下游排放，突出了 GIW 和下游排放之间地表水连通的潜在时期。累积起来，这些发现量化了季节性气候驱动因素对 GIW 水文和下游水域连通性的影响。