Evaluation of bamboos in eco-restoration of ‘jhum’ fallows in Arunachal Pradesh: ground vegetation, soil and microbial biomass

Abstract

With a view to identify potential bamboo species that can help in soil nutrient binding during restoration of abandoned shifting agricultural lands (jhum fallows), we analyzed the ground vegetation, soil and microbial properties under the canopy of three bamboo species viz., Bambusa nutans, Bambusa arundinacea and Dendrocalamus hamiltonii growing in a 9-year old jhum fallow in the ecologically fragile north-eastern hilly region of India. The results were compared with a grassland to evaluate the role of bamboos in soil nutrient dynamics. Species diversity of ground vegetation was highest under B. nutans canopy. Soil pH was neutral and the soil organic matter did not vary significantly between different species growing in the jhum fallow and grassland. Available forms of nitrogen and phosphorus in the soil showed variations among species. Soil microbial carbon and phosphorus were greater in grassland (control site), while microbial nitrogen was in B. nutans soil. Significant correlations existed amongst microbial carbon, nitrogen and phosphorus. The study indicates that B. nutans could help in rehabilitating the jhum fallows with special respect to soil nutrient enrichment.