Evaluation of different vermicomposts and conventional composts for their maturity indices

The present investigation was carried out during 2009–2010 to monitor the changes in maturity indices i.e total organic carbon, total nitrogen, C/N ratio, humic substances and humification index during conventional method of composting and vermicomposting of different organic residues i.e sugarcane trash, weeds, vegetable market waste and paddy straw. The results revealed that the total organic carbon and C/N ratio decreased while total nitrogen and humic substances increased with the passage of time during composting in all the organic residues. Vegetable market waste recorded narrow C/N ratio with high total nitrogen content in both the composting methods. Where paddy straw recorded less nitrogen with wide C/N ratio. The highest humic substances were observed in vegetable market waste vermicompost followed by weed vermicompost. Minimum per cent of humic substances were recorded with cane trash and rice straw. A well known index for humification is the HA/FA ratio, in both the composts paddy straw compost recorded low ratio and high ratio was recorded in vegetable market waste compost. Thus, vermicomposting offers a promising solution for the recycling of organic wastes into valuable organic manure within a short period of time over conventional composting.