Impact of environmental factors on aquatic biodiversity in roadside stormwater ponds

Zhenhua Sun,Ekaterina Sokolova,Sebastien Rauch,John E Brittain,Svein Jakob Saltveit,Sondre Meland

doi:10.1038/s41598-019-42497-z

Abstract

Constructed stormwater ponds mitigate runoff volumes and pollution, and provide other ecosystem services, such as supporting biodiversity, but these services attracted relatively less attention. The impacts of the pollution levels in the water column and sediments, the physical characteristics of ponds, and the presence of amphibians on the macroinvertebrate community composition and biodiversity were explored in twelve stormwater ponds in Norway. Also, the similarities between macroinvertebrate, zooplankton and plant communities were explored. Most of the taxa displayed in the ordination diagram were positively correlated with the pond size and the number of neighbouring ponds, and negatively correlated with the pollution levels in the water column and sediments. However, no statistically significant impacts on the number of taxa and Shannon index were observed. There were low similarities between the macroinvertebrate and zooplankton community compositions as well as between the plant and macroinvertebrate community compositions in the stormwater ponds. We observed a significant positive correlation between the number of plant and of zooplankton taxa, and a weak non-significant positive correlation between the number of plant and of macroinvertebrate taxa. Overall, the explanatory variables had a significant impact on the community composition, but not on the number of taxa nor Shannon index.

Highlights

Roads are widespread around most of the world, and people rely on vehicles for transportation in their daily life
The principal component analysis (PCA) scores extracted from axes 1 and 2 were used to plot the bar charts (Fig. 1b,c) and were used as proxies for pollution levels in the water column and sediments in further analysis
Within the taxa that were positively correlated with the pollution level in the water column, some of them are known to be very tolerant to pollution, e.g. Tanypodinae

Summary

Introduction

Roads are widespread around most of the world, and people rely on vehicles for transportation in their daily life. The increasing number of vehicles as well as road construction and maintenance increase pollutant loads from non-point sources, leading to potential impairment of the ecological conditions[1]. Road runoff contains various pollutants, e.g. metals, polycyclic aromatic hydrocarbons (PAHs), and salts[3,4], which can potentially affect the aquatic organisms in receiving water bodies[5]. In addition to the pollutants in the water column and sediments, ecological interactions, such as competition and predation, are a major aspect that affects biodiversity. The knowledge on impacts from pollutants in sediments and water column as well as ecological interactions enables a better understanding of the role of stormwater ponds in supporting and maintaining aquatic biodiversity.

Methods

Results

Discussion

Conclusion