English

Mercy Barasa,Wamiti Wanyoike,Kariuki Edward,Muchemi Gerald,Mbaria James,Gakuya Francis

doi:10.5897/jene2017.0628

Abstract

The study was carried out in six Kenyan rift valley lakes, Nakuru, Magadi, Oloiden, Crater (Sonachi), Bogoria and Elementaita with the aim to determine the levels of heavy metals and other metal elements (Co, Mn, Zn, Cu, Cr, Cd, Pb, Ni, Hg and As) in water and sediment samples as well as assess its association with water bird distribution. High levels of Pb (42 ppm) above the Pb benchmark levels (36 ppm) as per EPA (2007) benchmarks were detected in Lake Oloiden sediments. Lakes Bogoria and Elementaita had high levels of Mn (3676.7 ± 6652.3 and 747.55 ± 510.95, respectively), also above the Mn benchmark levels (631 ppm), according to EPA (2007). The mean sediment concentrations for Zn, Pb, Ni, As and Hg varied significantly (P 0.05). It was concluded that metals concentration in Kenyan Rift Valley lakes has no significant influence on the distribution of water birds. High Mn levels in lakes Bogoria and Elementaita, and Pb in Oloiden may cause toxic effects to the aquatic life and humans as a result of bioaccumulation. Key words: Ecotoxicology, heavy metals, water birds.

Highlights

Ecology is the scientific study of abundance, distributions and relations of organisms and their interaction with the environment (Begon et al, 2006)
Mercury, chromium and cadmium are among the copper, zinc and iron play a biochemical role in the life processes of all aquatic plants and animals
The mean concentrations of heavy metals Mn, Co, Cu, Zn, Cd, Cr, Pb, Hg, Ni and As analyzed in sediments and water samples from the six Rift valley lakes are showed in Tables 2, 3, 4, Appendix 1 and Appendix 2

Summary

Introduction

Ecology is the scientific study of abundance, distributions and relations of organisms and their interaction with the environment (Begon et al, 2006). A study on the association between water bird distribution and heavy metal concentration in the environment is needed. Baseline data on concentrations of Mn, Zn, Cu, Cd, Cr, Co, Ni, As, Pb and Hg in surface sediments and water samples from six Kenyan Rift Valley lakes (Nakuru, Magadi, Oloiden, Crater, Bogoria and Elementaita) is reported.

Results

Conclusion