Hydrologic processes regulate nutrient retention in stormwater detention ponds
Hydrologic processes regulate nutrient retention in stormwater detention ponds
复制标题
水文过程调节雨水滞留池的养分保留
DOI：
10.1016/j.scitotenv.2022.153722
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发表时间：
2022
影响因子：
9.8
通讯作者：
Gulliver, John S.
中科院分区：
文献类型：
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作者：
Janke, Benjamin D.;Finlay, Jacques C.;Taguchi, Vinicius J.;Gulliver, John S.
在世界许多地方的城市景观中，有管理的雨水池塘非常丰富，在减少城市径流和营养物污染方面发挥着重要但尚未得到充分研究的作用。人们普遍认为，水质的改善是由于营养物和其他污染物与颗粒物结合而沉降所致，而对水文和生态地球化学过程的考虑较少。为了提供改善池塘营养物保留管理的信息，我们研究了美国明尼苏达州双子城的三个成熟的城市滞留池，连续监测池塘水文以及氮和磷的浓度，并定期测量池塘的物理化学条件。在这三个地点，氮（>58%）和磷（>48%）的年养分保留率都很高，尽管由于年老和与低沼缺氧有关的内部负荷，磷的表现预期不佳。年度和事件规模的分析表明，强有力的水文控制养分保留，保留个别风暴事件强烈调节前期池塘蓄水能力。事件与净营养输出发生主要是由于低容量保留，而不是相对较高的流出浓度。总之，这些结果表明，了解和改善池塘水文功能是至关重要的，以提高管理雨水池塘的性能，以满足下游水质目标。
Managed stormwater ponds are abundant in urban landscapes in much of the world, performing vital but under-studied functions for attenuation of urban runoff and nutrient pollution. Water quality improvements are widely assumed to arise from settling of nutrients and other contaminants bound to particulates, with less consideration of hydrological and biogeochemical processes. To inform improved management of ponds for nutrient retention, we studied three mature urban detention ponds in the Twin Cities, MN, USA using continuous monitoring of pond hydrology and concentrations of nitrogen and phosphorus, coupled with periodic measurement of physiochemical conditions in the ponds. Across the three sites, annual nutrient retention was high for both nitrogen (>58%) and phosphorus (>48%) despite expectations of poor performance for phosphorus due to old age and internal loading linked to hypolimnetic anoxia. Both annual and event-scale analyses suggested strong hydrologic controls on nutrient retention, with retention for individual storm events strongly regulated by antecedent pond storage capacity. Events with net nutrient export occurred primarily due to low volume retention rather than relatively high outflow concentrations. Together these results suggest that understanding and improving pond hydrologic function is crucial to improving managed stormwater pond performance for meeting downstream water quality goals.