Water sustainability under climate change and increasing demand: a one water approach at a watershed scale

水将在本世纪初成为加拿大最重要的生态危机(Schindler 2001)。人们一再建议采用基于分水岭的水管理方法来解决水的可持续性问题。然而，这种方法的全面实施很少实现。全面了解水资源总量(气候、地表水、浅层和深层地下水等)而它们在分水岭尺度上的相互作用是一个主要障碍。我们建议从一个水的角度来评估气候变化和不断增加的社会经济用水需求驱动因素(农业和人口)下的流域可持续性，该流域位于不列颠哥伦比亚省南部内陆半干旱的奥卡纳根盆地(306平方公里)。适宜的流域大小和用水者之间的重大水冲突使该流域成为这项跨学科研究的理想场所。将结合地球化学和综合流域模型(Mike SHE或其他人)来量化总水资源、地表水-地下水连接和流域对各种水压力来源的响应。将使用加拿大陆地表面计划(CLASS)模型来改进对空间变化的地下水补给量的估计，以用于模型校准。此外，未来农业用水需求的预测将同时使用环境和经济驱动因素(产品价格、气候、水价政策和用水法规的变化)，而不是基于更简单的趋势预测。这项研究的新颖之处在于，它对分水岭规模的用水的物质层面和人文层面进行了量化整合，使之能够对气候变化和日益增加的需求影响做出适应性管理反应。

Water will become Canada's foremost ecological crisis early in this century (Schindler 2001). A watershed based approach for water management is repeatedly suggested to address water sustainability issues. However, full implementation of such an approach is seldom realized. Achieving a full understanding of total water resources (climate, surface water, shallow and deep groundwater etc.) and their interactions at a watershed scale is a major barrier. We propose to take a one-water perspective to evaluate watershed sustainability under climate change and increasing socio-economic drivers of water demands (agriculture and population) in the Deep Creek watershed (306 km2) located in the Okanagan basin of the semi-arid southern interior of British Columbia. The suitable watershed size and significant water conflicts among water users make this watershedan ideal place for this interdisciplinary research.  A combination of geo-chemistry and integrated watershed modelling (MIKE SHE or others) will be used to quantify the total water resource, surface water - groundwater connections and the watershed response to various water stressors. A Canadian Land Surface Scheme (CLASS) model will be used to improve estimationof spatially varied groundwater recharge for model calibration. In addition, future agriculture water demands will be projected using both environmental and economic drivers (changes in product prices, climate, water pricing policies, and water use regulations) rather than based on simpler trend projections. This study is novel in its quantitative integration of the physical and human dimensions of water use at a watershed scale, enabling adaptive management responses to climate change and increasing demand impacts.