Marsalek J, Rochfort Q, Grapentine L, Brownlee B
National Water Research Institute, Burlington, Ontario, Canada.
Water Sci Technol. 2002;45(3):255-63.
Impacts of urban development on a small creek with an on-stream stormwater pond, which was built to mitigate the effects of a 13-ha commercial plaza on creek flows, were assessed by investigations of the creek-pond system hydrology, water and sediment chemistry and toxicity, and benthic communities. The hydrology and conventional pollutant loadings of this system were dominated by the creek catchment (4.5 km2), which contributed more than 95% of the total flow; the rest was contributed by the plaza runoff which was less polluted than typical residential runoff. Conventional bioassays (Daphnia magna, Microtox) did not indicate any confirmed acute toxicity in the creek flow, plaza drainage, or pond outflow. However, sediments accumulated in the pond were rather polluted and several sediment bioassays (including Sediment Microtox) indicated their severe toxicity. In benthic community assessments, taxa richness and total counts of benthic organisms did not change much when moving from upstream to downstream of the pond. Thus, the pond accumulates sediments and toxicants and thereby prevents further degradation of the creek condition downstream of the plaza drainage outfall.
通过对小溪-池塘系统的水文、水和沉积物化学及毒性以及底栖生物群落进行调查，评估了城市发展对一条带有溪流雨水池塘的小溪的影响。该雨水池塘旨在减轻一个13公顷商业广场对溪流水流的影响。该系统的水文和常规污染物负荷主要由小溪集水区（4.5平方公里）主导，其贡献了总流量的95%以上；其余部分由广场径流贡献，广场径流的污染程度低于典型的住宅径流。常规生物测定（大型蚤、微毒检测）未表明溪流水流、广场排水或池塘流出水中存在任何已确认的急性毒性。然而，池塘中积累的沉积物污染相当严重，多项沉积物生物测定（包括沉积物微毒检测）表明其具有严重毒性。在底栖生物群落评估中，从池塘上游到下游，底栖生物的分类丰富度和总数变化不大。因此，池塘积累了沉积物和有毒物质，从而防止了广场排水口下游小溪状况的进一步恶化。
