International Journal of Applied Research
Vol. 1, Issue 12, Part K (2015)
Variations in bacterial population numbers and enzyme activities in different land-use systems of Brahmaputra valley, Assam
Bhattacharyya PN, Jha DK
A culture-based approach was used, in the present investigation, to assess the soil bacterial diversity, while enzyme activities such as dehydrogenase, phosphatase and urease were estimated using standard protocols. Degraded forest (DF) and relatively less disturbed forest (RLDF) were the two different land-use systems used, here, to assess the soil bacterial diversity and enzymatic activity. Soil samples were collected randomly at different depths, in four different seasons. A total of 76 bacterial isolates were isolated and characterized based on their morphological and biochemical properties. Occurrence of Gram-negative bacteria were more over Gram-positive bacteria. More bacterial population numbers and enzyme activities were recorded at surface soil that decreased with increase in vertical depths. Maximum bacterial populations as well as activities of different enzymes were recorded during spring season at RLDF while the value was minimum during winter season at DF. Bacterial genera like Actinobacteria sp., Burkholderia sp., Chromobacterium sp.Escherichiarncoli, Enterobacter sp., Micrococcus sp., Pseudomonas sp., Serratia sp., showed their restricted distributions at particular land-use system. Significant positive correlation was observed between the bacterial population number and soil pH at both the surface and subsurface soils (R2=0.993 and 0.954 respectively) in RLDF. The data are significantly different from each other at significance level of P< 0.05. The results of the present investigation indicated that difference in soil depth, seasonal variation and land-use systems has a potential influence on the existence of bacterial population numbers and soil enzyme activities.
How to cite this article:
Bhattacharyya PN, Jha DK. Variations in bacterial population numbers and enzyme activities in different land-use systems of Brahmaputra valley, Assam. International Journal of Applied Research. 2015; 1(12): 762-766.