Linking urban land use to pollutants in constructed wetlands: Implications for stormwater and urban planning
Linking urban land use to pollutants in constructed wetlands: Implications for stormwater and urban planning
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DOI：
10.1016/j.landurbplan.2016.12.016
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发表时间：
2017-06
影响因子：
9.1
通讯作者：
David J. Sharley;Simon M. Sharp;S. Marshall;Katherine J Jeppe;V. Pettigrove
中科院分区：
文献类型：
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作者：
David J. Sharley;Simon M. Sharp;S. Marshall;Katherine J Jeppe;V. Pettigrove
人工湿地被认为是城市景观中一种具有成本效益且社会可接受的雨水处理方案，可满足一系列城市设计目标，包括防洪和处理雨水。虽然湿地也为水生生物群提供栖息地，并且常常充当野生动物的避难所，但人们越来越担心，随着湿地受到污染，它们可能对水生生物产生毒性，并导致沉积物处理的巨额成本。目前，很少考虑湿地流域的土地利用活动如何造成这种污染。在这里，我们评估了城市景观中 98 个人工湿地的沉积物质量，并确定了污染物浓度是否与流域土地利用、地质或湿地年龄相关。使用增强回归树，我们发现土地利用类型是沉积物中重金属和石油碳氢化合物浓度的重要决定因素。流域内工业超过 10% 的湿地的沉积物中微量金属浓度明显高于工业化程度较低的排水流域的湿地。此外，这些工业湿地超出生态和废物处理准则的风险要大得多，而流域主要由住宅区或城市周边组成的湿地受到污染的风险要低得多。结果还表明，湿地的年龄及其流域地质显着影响沉积物质量。这项研究增进了我们对影响城市地区污染的因素的了解，并使湿地能够得到更好的设计和管理，以最大限度地减少其环境影响和维护成本。
Constructed wetlands are recognised as a cost-effective and socially acceptable stormwater treatment option within urban landscapes, satisfying a range of urban design objectives, including flood protection and treating stormwater. While wetlands also provide habitat for aquatic biota, and often act as a refuge for wildlife, there is growing concern that as wetlands become polluted, they could become toxic to aquatic life and lead to extensive costs for the disposal of sediments. Currently, there is little consideration given to how land use activity in wetland catchments contributes to this pollution. Here we assessed the sediment quality of 98 constructed wetlands across an urban landscape and determined whether concentrations of pollutants present can be correlated to catchment land uses, geology or wetland age. Using boosted regression trees, we find that land use type is an important determinant of the concentrations of heavy metals and petroleum hydrocarbons in sediments. Wetlands with >10% industries in their catchments have significantly higher sediment-bound concentrations of trace metals than wetlands draining catchments with little industrialisation. Furthermore, these industrial wetlands have a much greater risk of exceeding ecological and waste disposal guidelines, while wetlands with catchments comprising primarily residential orperi-urban have significantly lower risk of becoming polluted. Results also suggest that the age of wetlands and their catchment geology significantly influences sediment quality. This research improves our understanding of the factors influencing pollution in urban areas and will enable wetlands to be better designed and managed to minimise their environmental impacts and maintenance costs.