Effect on Growth of Earthworm and Chemical Parameters During Vermicomposting of Pressmud Sludge Mixed with Cattle Dung Mixture

The aim of present work was to assess the growth of earthworm Eisenia fetida during vermicomposting of pressmud (PM) sludge. It was mixed with cattle dung (CD) at different ratios (PM: CD) of 0:100 (PM0) 25:75 (PM25), 50:50 (PM50), 75:25 (PM75) and 100:0 (PM100) under different varying weight 8.76 (PM0), 7.63 (PM25), 9.93 (PM50), 9.90 (PM75) and 10.23 g (PM100). Co-composting with cattle dung helped to improve their acceptability for E. fetida and also improved physico-chemical characteristics. Best suitable mixture for highest survival, maximum weight and highest population buildup of E. fetida was determined by observing growth rate, weight, mortality, rate of cocoon production and population buildup. Minimum mortality and highest weight (77 g) of worms were observed in 25:75 (PM25) mixture of PM. However, increasing percentages of wastes significantly affected the number and weight of worms. Nitrogen, phosphorus, sodium, increased from initial feed mixture to final products, while organic carbon, C:N ratio and Potassium showed an opposite trend. Heavy metals (Copper, Chromium, Iron) decreased significantly from initial except Zinc and manganese which accumulate significantly.