Development of phosphorus loading control strategies for urbanizing watersheds

磷负荷和加速富营养化对人类和环境健康具有负面影响，并具有重大的潜在经济影响。据报道，在加拿大的几个地区，藻华的频率有所增加，来自城市和农村非点源的磷负荷被怀疑是主要原因。水系统中营养状态的变化影响了将水资源用于娱乐目的的能力，增加了水处理成本，并降低了水生生物多样性。目前，仅基于对磷负荷的担忧，加拿大几个地区正在对新开发项目实施限制。在城市化的流域中，雨水可以成为接收水体磷的主要来源。处理湿地由于其低维护要求、弹性和美观性，已被确定为减轻城市雨水中磷负荷的可能工具。然而，关于雨水湿地中磷的命运，特别是在凉爽气候下，存在着重大的知识空白。本研究项目的短期目标是确定雨水处理湿地的磷保留机制，并开发创新的设计和操作方法，可用于优化冷气候湿地系统的磷去除。该研究计划将包括控制实验室实验，涉及全尺度雨水湿地系统的实地研究，以及开发一种新的、凉爽气候的、基于过程的湿地模型。研究活动将集中在接收来自哈利法克斯新城市开发的雨水的湿地系统上，该系统将作为“生活实验室”。各种各样的学生将在博士、硕士和本科阶段接受培训，并将获得使用最先进的环境监测仪器的经验。这项研究将导致工具和设计建议的发展，雨水工程师和市政规划者可以直接使用，以确保保护宝贵的水生资源。**

Phosphorus loading and accelerated eutrophication have negative effects on human and environmental health, and significant potential economic impacts. Increases in the frequency of algal blooms has been reported in several regions of Canada, with phosphorus loading from non-point urban and rural sources as suspected primary causes. Changes in trophic state within a water system influences the ability to use the water resource for recreational purposes, increases water treatment costs, and degrades aquatic biodiversity. Restrictions are currently being placed on new development in several regions of Canada based solely on phosphorus loading concerns. Within urbanizing watersheds, stormwater can be a major source of phosphorus to receiving water bodies. Treatment wetlands have been identified as a possible tool for mitigating phosphorus loading from urban stormwater due to their low maintenance requirements, resiliency, and aesthetic appeal. However, there are significant knowledge gaps with respect to the fate of phosphorus within stormwater wetlands, especially in cool climates. The short term goals of this research program are to identify mechanisms of phosphorus retention with stormwater treatment wetlands, and develop innovate design and operation approaches that can be used to optimize phosphorus removal in cool climate wetland systems. The research program will involve controlled laboratory experiments, field studies involving full scale stormwater wetland systems, and the development of a new, cool climate, process-based wetland model. The research activities will focus on a wetland system receiving stormwater from a new urban development in Halifax, that will serve as a "Living Laboratory". A diversity of students will be trained at the doctoral, masters and undergraduate levels, and will gain experience using state-of-the-art environmental monitoring instruments. This research will lead to the development of tools and design recommendations that can be directly used by stormwater engineers and municipal planners to ensure protection of valuable aquatic resources. **