Impact of Different Land use Management on Soil Enzyme Activities and Bacterial Genetic Finger Prints of North-Western Himalayas

Abstract

Land uses has significant impact on soil biological properties that incessantly intimates the soil quality change and are assessed by soil microbial and biochemical indicators, as they are highly sensitive to change in environment. The purpose of this study was to investigate the impact of land use on soil enzyme activities and gene diversity in selected location of Northwestern Himalayas, India. Nine different land use system of similar soil type at depth 0-15cm were analyzed for soil enzymes (Dehydrogenase, Acid Phosphatase, Alkaline Phosphatase, Nitrate Reductase, Arylsulphatase, and Phytase) and genetic fingerprints (Randomly Amplified Polymorphic DNA) analysis. The land use systems investigated are Oak (Quercus incana), Deodar (Cedrus deodara), Pine (Pinus roxburghii) trees, Apple orchids and crop based systems in uplands and valleys. All the soil enzymes were significantly higher in forest ecosystem followed by organic farm and conventional maize-wheat farm soil. The principal component analysis (PCA) of nine different land use systems based on soil enzymes shows significant variation in data and all the long-term agricultural lands were segregated together. However maize-wheat and organic farm are group together in the PCA plot. Hierarchical clustering by wards method of soil enzymes clusters the deodar forest soil, oak forest soil and organic farming in one cluster and segregates remaining land use system in another. RAPD analysis showed high polymorphism between samples and similarity indexing using unweighted pair-group method with arithmetic averages resulted in four clusters. Land use showed significantly negative impact on soil enzymes and genetic fingerprints in long-term agricultural lands as compared to natural forest ecosystem and organic farming as reveal by RAPD assisted marker.