Please cite this article in press as: Stephansen, D.A., et al., Distribution of metals in fauna, flora and sediments of wet detention ponds and natural shallow lakes. Ecol. Eng. (2013), http://dx.doi.org/10.1016/j.ecoleng.2013.05.007 ARTICLE IN PRESS G Model ECOENG-2568; No. of Pages 9 Ecological Engineering xxx (2013) xxx–xxx Contents lists available at SciVerse ScienceDirect Ecological Engineering journa l h om epage: www.elsevier.com/locate/ecoleng Distribution of metals in fauna, flora and sediments of wet detention ponds and natural shallow lakes Diana A. Stephansen a,∗ , Asbjørn H. Nielsen a , Thorkild Hvitved-Jacobsen a , Carlos A. Arias a , Hans Brix b , Jes Vollertsen a a Department of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark b Department of Bioscience, Plant Biology, Aarhus University, Ole Worms Allé 1, 8000 Aarhus C, Denmark a r t i c l e i n f o Article history: Received 31 October 2012 Received in revised form 20 May 2013 Accepted 23 May 2013 Available online xxx Keywords: Heavy metals Detention ponds Bioaccumulation Biodiversity Aquatic ecosystems a b s t r a c t Fauna, flora, and sediment were collected from 9 wet detention ponds receiving stormwater runoff and 11 small natural shallow lakes. The fauna and flora samples were sorted into species or groups of species and, together with sediments, analyzed for aluminum, copper, iron, zinc, arsenic, cadmium, chromium, nickel, lead, and phosphorus. There was a trend toward the studied wet detention ponds being more polluted by metals than the lakes. For the fauna this trend was statistically significant for all metals, while it for the plants was statistically significant for most of the metals. For the sediments, however, this observed trend was not statistically significant for any of the metals. Comparing the different metals accumulated in the sediments, the fauna, and the flora, no correlation between any of these could be detected. Neither fauna nor flora metal concentrations did correlate with sediment metal concentrations, and fauna metal concentrations did not correlate with flora metal concentrations. Comparing the diversity of species in the wet detention ponds and the shallow lakes, molluscs were more abundant in the wet detention ponds. For other fauna and flora, no clear difference between the diversity of species was observed. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Stormwater runoff from urban areas, roads and highways con- tains pollutants that originate from the catchment surfaces. In most cases, the runoff conveys the pollutants to a receiving water body where they potentially cause harm (Grapentine et al., 2004). To mitigate environmental impacts on aquatic ecosystems, it is com- mon practice to establish some treatment of the runoff prior to its discharge. One of the most common treatment options is wet detention pond (Hvitved-Jacobsen et al., 2010). A well-designed wet detention pond detains a large fraction of the particle-bound pollutants and stores it in the bottom sediments (Pontier et al., 2004). Typically, a wet detention pond has a permanent water body of 0.5–2 m depth and a surface area of some thousand square meters depending on the catchment area. A wet detention pond is typically constructed as an earthen basin with one or more inlets and one outlet. Its morphology is therefore rather similar to that of small natural shallow lakes. Stormwater wet detention ponds are designed as treatment facilities, but as they in many ecological aspects resemble natu- ral lakes, they quickly become invaded by aquatic flora and fauna. ∗ Corresponding author. Tel.: +45 41 56 28 82. E-mail address: dac@bio.aau.dk (D.A. Stephansen). Wet detention ponds, hereby, act as aquatic ecosystems suppor- ting the flora and fauna living there (Scher et al., 2004). However, wet detention ponds are designed to retain and accumulate pol- lutants in the bottom sediments and the flora and fauna therefore live in an environment of elevated pollutant content. Whether such ponds ultimately have positive overall effects on the biodiversity in a region is a topic of discussion, but some studies point toward this being the case (e.g. Le Viol et al., 2009; Brand and Snodgrass, 2010), while other studies point toward the fact that the ecological risks are not completely understood (Tixier et al., 2011). One major group of pollutants retained in wet detention ponds is metals, which usually occur in elevated concentrations in the bottom sediments. The elevated metal concentrations may con- stitute a pool from where metals can migrate into aquatic plants and animals where they might accumulate in the tissue. For exam- ple Campbell (1994) reported elevated concentrations of certain heavy metals in fish from wet detention ponds compared to fish from rural shallow lakes. Stephansen et al. (2012) compared fauna from five wet detention ponds and five natural shallow lakes and found that metals were generally elevated in fauna from the ponds. For plants from anthropogenic lakes, Samecka-Cymerman and Kempers (2001) reported elevated concentrations of several heavy metals. Comprehensive studies covering metals in aquatic flora, fauna, and sediments simultaneously are scarce. Reported studies have 0925-8574/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.ecoleng.2013.05.007