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Abstract: Experiments were conducted to remove heavy metals (Cr, Cd, Pb, Cu and Zn) from urban sewage sludge (SS) amended with spent mushroom compost (SMC) using worms, Lumbricus rubellus, for 105 days, after 21 days of pre-composting. Five combinations of SS/SMC treatments were prepared in triplicate along with a control for each treatment in microcosms. Analysis of the earthworms'' multiplication and growth and laboratory analysis were conducted during the tenth and fifteenth week of vermicomposting. Our result showed that the final biomass of earthworms (mg) and final number of earthworms showed significant differences between treatments i.e. F=554.70, P=0.00 and F=729.10, P=0.00 respectively. The heavy metals Cr, Cd and Pb contained in vermicompost were lower than initial concentrations, with 90–98.7percent removal on week ten. However, concentrations of Cu and Zn, that are considered as micronutrients, were higher than initial concentrations, but they were 10–200-fold lower than the EU and USA biosolid compost limits and Malaysian Recommended Site Screening Levels for Contaminated Land (SSLs). An increment of heavy metals were recorded in vermicompost for all treatments on week fifteen compared to week ten, while concentration of heavy metals in earthworms'' tissue were lower compared to vermicompost. Hence, it is suggested that earthworms begin to discharge heavy metals into their surroundings and it was evident that the earthworms'' heavy metals excretion period was within the interval of ten to fifteen weeks. [Copyright &y& Elsevier]

This paper presents a review of the existing knowledge on the application of earthworms, both native and exotic species for waste land reclamation, increasing plant productivity with reference to tea production in Indian sites, plant growth and productivity in Indian and world sites and application of vermicompost for increased plant growth in some Indian sites. The paper identifies Indian species of earthworms to be employed in vermitechnology. Based on the existing knowledge, the areas of future research and funding on vermitechnology have been identified. [ABSTRACT FROM AUTHOR]

Biodiversity is one of the most important areas of environmental research, management and concerns. Our understanding about belowground biodiversity and its functions is not as strong as that on aboveground bioctiversity. This paper presents a review of the existing knowledge on soil fauna, with particular reference to (i) community structure, biomass and population turnover in different land uses; (ii) bioturbation activity; (iii) soil fauna - soil micro-flora interaction; (iv) role of soil fauna in land reclamation; and (v) vermitechnology. Based on the existing knowledge, the areas of future research for conservation and management of below ground biodiversity have been identified. [ABSTRACT FROM AUTHOR]