Litter mass loss rate changes as function of soil microbial diversity and litter chemical quality in tropical and sub-tropical forest of Mizoram: A microcosm study

Soil microbes (populations of fungi, actinomycetes and bacteria) and C/N ratio are among important factors influencing the process of litter decomposition in variety of ecosystems. The present study aimed to assess changes in soil microbial populations and C/N ratio in decomposition of mixed litters of tropical (~100 m) and subtropical (~1450 m amsl altitude) forests under laboratory microcosm experiment. Microcosms were made of PVC pipe fitted with a screw lid with a sealed bottom. Microcosms consist of mixture of mineral soil and surface organic horizon (3: 1) collected from the two contrasting forests of Mizoram. Mixed senesced litters collected from two forests were air dried and 5g of air-dried litter samples were placed in replicated laboratory microcosm. The samples were moistened regularly at every third day. Five replicated samples were recovered periodically up to 180 days after experimental setup. Mass loss was rapid in initial stages (up to 40 days) which decrease at the end of the retrieval period. Mass loss rates in sub-tropical forest litter changes as function of soil and litter N, whereas the same in tropical forest was regulated by fungi, actinomycetes and litter C/N ratio.