Nutrient cycling and metabolic activity of soil microbes in pristine forests in comparison to a monoculture

Abstract

Soil health in terms of nutrient cycling, metabolic activities and microbial diversity is measured and compared among four different forests in Gangajalghati forest area of Bankura district, West Bengal, India. Three of these forests are of pristine nature and one is Eucalyptus monoculture. The microbial diversity in terms of species richness is considerably higher in pristine forests as compared to the Eucalyptus monoculture. The P values determined using statistical tools like Wilcoxon rank sum test and Kolmogrov Smirnov test reveal significant difference in carbon and nitrogen contents and also in acid phosphatase activity between the pristine forests and the man-made monoculture forest. The elemental analysis through EDX also suggests a better nutrient cycling owing to greater microbial activity in the pristine forests than its monoculture counterpart. It also revealed a higher concentration of some heavy metals viz., Cd, Pb and Cr in the monoculture type forest. However, phosphorus content, basal respiration and dehydrogenase (DHA) activities remains to be the same in these characteristically two types of forests. Most of the parameters indicate a poor nutrient shuffling and microbial diversity in the man-made monoculture of Eucalyptus and a reforestation practice of this kind is not encouraging.