分水岭恢复力是分水岭保持其特征系统状态的能力,同时抵抗,适应,和水文后的重组(例如,干旱,洪水)或生物地球化学(例如,过多的营养)干扰。脆弱水域包括非洪泛区湿地和源头水流,丰富的分水岭成分代表了淡水水生网络的最远范围。脆弱水域是水文动态和生物地球化学反应的水生系统,存储,processing,并释放水和夹带物(即,溶解和颗粒)材料沿着不断扩大和收缩的水生网络。从这些过程中出现的水文和生物地球化学功能影响的大小,频率,定时,持续时间,storage,以及流域组成部分和下游水域之间的物质和能量通量变化率,从而保持分水岭状态并赋予分水岭复原力。我们在这里提出了一个概念框架,用于了解脆弱的水域如何赋予流域复原力。我们展示了个体和累积的脆弱水修改(例如,程度降低,连通性改变)影响流域尺度水文和生物地球化学扰动响应和恢复,这会降低分水岭弹性,并可能触发跨阈值过渡到替代分水岭状态(例如,有利于增加洪水频率或养分浓度的州)。随后,我们描述了弹性流域如何在陆地系统和下坡水之间的水文和生物地球化学相互作用中需要空间异质性和时间变异性,这需要注意脆弱水域的保护和恢复及其下游连通性梯度。最后,我们为弹性流域提供可行的原则,并阐明研究需求,以进一步推进流域弹性科学和脆弱水管理。
Watershed resilience is the ability of a watershed to maintain its characteristic system state while concurrently resisting, adapting to, and reorganizing after hydrological (for example, drought, flooding) or biogeochemical (for example, excessive nutrient) disturbances. Vulnerable waters include non-floodplain wetlands and headwater streams, abundant watershed components representing the most distal extent of the freshwater aquatic network. Vulnerable waters are hydrologically dynamic and biogeochemically reactive aquatic systems, storing, processing, and releasing water and entrained (that is, dissolved and particulate) materials along expanding and contracting aquatic networks. The hydrological and biogeochemical functions emerging from these processes affect the magnitude, frequency, timing, duration, storage, and rate of change of material and energy fluxes among watershed components and to downstream waters, thereby maintaining watershed states and imparting watershed resilience. We present here a conceptual framework for understanding how vulnerable waters confer watershed resilience. We demonstrate how individual and cumulative vulnerable-water modifications (for example, reduced extent, altered connectivity) affect watershed-scale hydrological and biogeochemical disturbance response and recovery, which decreases watershed resilience and can trigger transitions across thresholds to alternative watershed states (for example, states conducive to increased flood frequency or nutrient concentrations). We subsequently describe how resilient watersheds require spatial heterogeneity and temporal variability in hydrological and biogeochemical interactions between terrestrial systems and down-gradient waters, which necessitates attention to the conservation and restoration of vulnerable waters and their downstream connectivity gradients. To conclude, we provide actionable principles for resilient watersheds and articulate research needs to further watershed resilience science and vulnerable-water management.