Landuse and climate change: Impacts on Ontario's water resources

土地利用和土地覆盖(LULC)在世界许多发达地区都是动态的，在安大略省南部尤其如此，那里居住着近1/4的加拿大人口，气候和土壤条件最有利于农业。事实上，农业无处不在地包围着安大略省南部的城市地区，优质农业用地和庞大且不断增长的人口之间的交汇对水资源构成了特别的挑战。气候多变性也是常态，气候变化和极端天气对水资源的影响在发达地区往往被放大。然而，很少有关于季节性积雪覆盖的发达地貌中的水文气候扰动的研究，而且通常更多地关注暖季的极端降水(即风暴、干旱)。此外，很少有人研究所谓的“可持续”土地利用、土地利用的变化和分水岭尺度上的气候变化的相互影响。LULC可以放大水资源对气候变化的敏感性的观察启发了拟议的研究计划，该计划有两个主要问题：(1)过去和现在的LULC和气候变化如何影响安大略省南部的水量和水质？以及，(2)可持续的做法是否具有预期的效果？这些问题将通过各种办法加以解决，利用现有的长期监测数据以及新的、在空间和时间上密集的分水岭测量。研究将集中在安大略湖盆地，从多伦多和贝尔维尔之间延伸，从安大略湖海岸线向北延伸到橡树岭莫雷恩。这一地区特别适合区分气候和土地利用变化对水量和水质的累积影响，因为它正在经历城市扩张和农业集约化以及土地利用方式的转变。它也是西顿开发区的所在地，该开发区被指定为可持续发展的城市社区，在加拿大是独一无二的。重要的是，安大略省这一地区没有伊利湖流域那样的集约农业历史，因此许多区域长期水量和水质监测站是在变化开始之前建立的。虽然将测量各种水质参数，但这项研究的主要重点将是主要营养物质：碳、氮和磷。

Land use and land cover (LULC) are dynamic in many developed parts of the world, and this is particularly true in southern Ontario, where nearly ¼ of the Canadian population resides and where climatic and soil conditions are most favourable for agriculture. Indeed, agriculture ubiquitously surrounds urban areas in S. Ontario, and this intersection between prime agricultural land and a large and growing population poses particular challenges for water resources. Climate variability is also the norm and the impacts of climate shifts and extreme weather on water resources are often amplified in developed landscapes. However, there are few studies of hydroclimatic perturbations in developed landscapes that have seasonal snow cover, and generally there has been a greater focus on precipitation extremes during the warm season (i.e. storms, droughts). In addition, there have been few, if any studies of the interactive impacts of so-called sustainable' LULC and climate variability at the watershed scale. The observation that LULC can amplify the sensitivity of water resources to climate change inspired the proposed research program, which has two primary questions: (1) how have past and current LULC and climate shifts affected water quantity and quality in southern Ontario? And, (2) are sustainable' practices having the desired effect? These questions will be addressed through a variety of approaches, utilizing existing long-term monitoring data as well as new, spatially and temporally intensive watershed-based measurements. Research will be focused in the Lake Ontario basin, extending between Toronto and Belleville and from the Lake Ontario shoreline northwards to the Oak Ridges Moraine. This area is particularly appropriate for disentangling the cumulative influence of climate and LULC change on water quantity and quality because it is undergoing both urban expansion and agricultural intensification as well as shifts in land use practices. It is also home to the Seaton Development area, which has been designated a sustainable urban community' and is unique in Canada. Importantly, this part of Ontario does not have the same long history of intensive agriculture as the Lake Erie basin and therefore many of the regional long-term water quantity and quality monitoring stations were established before change began. While a variety of water quality parameters will be measured, the primary focus of this research will be on the major nutrients: carbon, nitrogen and phosphorus.