Structural Alterations in Aquatic Insect Communities Exposed to Copper in Laboratory Streams

Abstract

The effects of copper on aquatic insect communities were examined using rock-filled trays colonized in the field for 30 d, transferred to laboratory streams, and dosed with CuSO4. Each stream was randomly assigned to one of three treatments: control (0 pg/L), low dose (15-32 pg/L), and high dose (135-178 pg/L). Experiments were replicated over three seasons. Exposure to copper for 96 h significantly reduced both the total number of individuals and number of taxa during each season, with greatest effects observed in summer. Owing to differences in sensitivity to copper, the percent composition of dominant orders of aquatic insects varied among treatments. The relative abundance of Ephemeroptera decreased in treated streams during each season. The response of other aquatic insects, including Diptera and Plecoptera, varied between seasons, but these groups were generally less sensitive to copper exposure. These results indicate that the artificial substrates employed in this study are amenable to experimental manipulation and will provide a unique opportunity to examine the community responses of aquatic insects to toxicants under environmentally realistic conditions.

Response of macroinvertebrates to copper and zinc in a stream mesocosm

“…Responses of benthic communities to heavy metals in these chronic mesocosm experiments were generally similar to those reported from field studies of metal-polluted streams in North America [25,26], Europe [27], and New Zealand [3], and in North American laboratory experiments [28][29][30]. Specifically, mayflies and some stoneflies were sensitive, and caddisflies and chironomids were relatively tolerant of metal exposure.…”

Survival and Behavioral Responses of Larvae of the Caddisfly Hydropsyche Angustipennis to Copper and Diazinon

“…Indeed, the low 48-h EC50 value for altered activity patterns presented here for H. angustipennis (17 g/L) may be indicative of chronic effects, because in life-cycle tests with the caddisfly Clistoronia magnifica, Nebeker et al [45] demonstrated a significant reduction in adult emergence at 13 g Cu/L and a prevented life-cycle completion at 17 g Cu/L. Based on monitoring studies, it is known that concentrations as low as 12 to 32 g Cu/L strongly reduce the abundance and diversity of aquatic insect species [46,47]. In addition, the isopod Asellus aquaticus appeared to be unable to survive during chronic exposure to 5 g Cu/L [48], and the midge Polypedilum nubifer exhibited a decreased emergence at 10 g Cu/L [49].…”

Integrative assessment of benthic macroinvertebrate community impairment from metal‐contaminated waters in tributaries of the upper Powell River, Virginia, USA

“…These toxic acids and metals flow to surface waters, where the acid is eventually neutralized, causing metals to precipitate and coat streambeds with metal oxides, impairing habitat and adversely affecting water quality in over 13,000 mi of U.S. rivers [1]. The biotic effects associated with AMD impacted surface waters include acute impairment of benthic and fish communities as a result of low pH and elevated levels of dissolved heavy metals [2][3][4][5]. A decrease in benthic macroinvertebrate diversity and an increase of tolerant organisms are also often associated with heavy metal pollution in streams.…”