Arbuscular Mycorrhizal Fungi Diversity in Selected Heavy metal Contaminated Soils in Owerri, Nigeria

摘要

An investigation was carried out on the species diversity of Arbuscular mycorrhizal (AM) fungi in selected heavy metal contaminated soils within Owerri metropolis. Soils (0-20cm) were collected from 8 different locations viz (1) high auto mechanic activity area. (2) Medium auto mechanic activity area. (3) Low auto mechanic activity area. (4) Old dump site. (5) Active dump site. (6) Recovery dump site. (7) Heavy traffic highway. (8) Undisturbed vegetative land that served as control. Soil samples were analyzed for physicochemical parameters including heavy metal viz lead (Pb), Cadmium (Cd) and Zinc (Zn). Also the ecological characteristics of AM fungi species were determined. Results showed that areas with high pollution index (PI) adversely affected the richness and diversity of AM fungi species. Seven different AM fungi ecotypes were isolated from the soil samples. These ecotypes had varied relative abundance across the locations. Species richness and diversity as measured by Shannon-Wiener index decreased in soils with PI > 20 but increased with low PI < 20. However, these organisms maintained significant populations across the locations. Thus suggesting high possibility of facilitating microbial activity in heavy metal stressed soil ecosystems.