Ecol Appl. 2014 Jan;24(1):142-57. doi: 10.1890/13-0202.1.
Global wetland biodiversity loss continues unabated, driven by increased demand for freshwater. A key strategy for conservation management of freshwater systems is to maintain the quantity and quality of the natural water regimes, including the frequency and timing of flows. Formalizing an ecological model depicting the key ecological components and the underlying processes of cause and effect is required for successful conservation management. Models linking hydrology with ecological responses can prove to be an invaluable tool for robust decision-making of environmental flows. Here, we explored alternative water management strategies and identified maximal strategies for successful long-term management of colonial waterbirds in the Macquarie Marshes, Australia. We modeled fluctuations in breeding abundances of 10 colonial waterbird species over the past quarter century (1986-2010). Clear relationships existed between flows and breeding, both in frequencies and total abundances, with a strong linear relationship for flows > 200 GL. Thresholds emerged for triggering breeding events in all 10 species, but these varied among species. Three species displayed a sharp threshold response between 100 GL and 250 GL. These had a breeding probability of 0.5 when flows were > 180 GL and a 0.9 probability of breeding with flows > 350 GL. The remaining species had a probability greater than 0.5 of breeding with flows > 400 GL. Using developed models, we examined the effects of five environmental flow management strategies on the variability of flows and subsequent likelihood of breeding. Management to different target volumes of environmental flows affected overall and specific breeding probabilities. The likelihood of breeding for all 10 colonial waterbirds increased from a regulated historical mean (+/-SD) of 0.36 +/- 0.09 to 0.53 +/- 0.14, an improvement of 47.5% +/- 18.7%. Management of complex ecosystems depends on good understanding of the responses of organisms to the main drivers of change. Considerable opportunity exists for implementing similar frameworks for other ecosystem attributes, following understanding of their responses to the flow regime, achieving a more complete model of the entire ecosystem.
全球湿地生物多样性持续减少，这主要是由于对淡水的需求不断增加所致。保护管理淡水系统的关键策略是维持自然水情的数量和质量，包括水流的频率和时间安排。为了成功进行保护管理，需要制定一个正式的生态模型，描绘关键生态组成部分以及因果关系的基本过程。将水文学与生态响应联系起来的模型可以成为制定环境水流稳健决策的宝贵工具。在这里，我们探讨了替代的水管理策略，并确定了澳大利亚麦夸里沼泽地成功长期管理殖民水鸟的最大策略。我们对过去四分之一个世纪（1986-2010 年） 10 种殖民水鸟繁殖数量的波动进行了建模。水流与繁殖之间存在明确的关系，无论是在频率还是总数量上，对于 >200GL 的水流都存在很强的线性关系。所有 10 种物种的繁殖事件都出现了触发阈值，但这些阈值在物种之间有所不同。三种物种在 100GL 到 250GL 之间显示出明显的阈值响应。当水流 >180GL 时，繁殖概率为 0.5，当水流 >350GL 时，繁殖概率为 0.9。其余物种的水流 >400GL 时繁殖概率大于 0.5。使用开发的模型，我们研究了五种环境水流管理策略对水流变异性和随后繁殖可能性的影响。针对不同目标体积的环境水流管理会影响整体和特定繁殖的可能性。所有 10 种殖民水鸟的繁殖可能性从有调节的历史平均值（+/-SD）0.36 +/- 0.09 增加到 0.53 +/- 0.14，提高了 47.5% +/- 18.7%。复杂生态系统的管理取决于对生物体对主要变化驱动因素的反应的良好理解。在了解其对水流状况的反应后，为其他生态系统属性实施类似框架提供了相当大的机会，从而实现整个生态系统更完整的模型。
