Physiological responses of a tropical earthworm: a potential tool for biomonitoring heavy metal pollution in tropical wetlands
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Date
2016
Authors
Dada, E. O.
Njoku, K. L.
Osuntoki, A. A.
Akinola, M. O.
Journal Title
Journal ISSN
Volume Title
Publisher
Ecological Society of Nigeria
Abstract
Wetlands play important ecological and life-supporting roles. Therefore, appropriate and adequate wetland biomonitoring options should be available. This study investigated the burrowing and survival responses of a wetland earthworm (Libyodrilus violaceus) to heavy metal (Zn, Pb, Cd) polluted soil. The worms were exposed to soils contaminated with graduated levels of heavy metals in the laboratory and their responses evaluated following standard procedures. The median lethal concentration (LC) values for Zn, Pb, and Cd obtained from the study were 520.06 mg/kg, 1551.55 mg/kg, and 706.66 mg/kg soil respectively. The mixture of Zn and Cd gave a 14-day LC50 value of 626.12 mg/kg soil, while the combined action of Zn, Pb and Cd gave a 14-day LC50 value of 1,273.47 mg/kg soil. The species also showed delayed burrowing responses to these metals in individual and combined concentrations. These results suggest that L. violaceus could be a candidate for assessing the heavy metal state of tropical wetland soils.
Description
Staff publications
Keywords
Burrowing , Libyodrilus violaceus , Wetlands , Ecology , Research Subject Categories::NATURAL SCIENCES::Biology::Cell and molecular biology
Citation
Dada, E. O. Njoku, K. L. Osuntoki, A. A. Akinola, M. O. (2016). Physiological responses of a tropical earthworm: a potential tool for biomonitoring heavy metal pollution in tropical wetlands. Nigerian Journal of Ecology. 15(1), 11-18pp.