Chapter 13 Vermicompost as a Biological Soil Amendment J. Tajbakhsh, E. Mohammadi Goltapeh, and Ajit Varma 13.1 Introduction Today, the viability of using earthworms as a treatment technique for numerous waste streams has been well established. Vermicompost is considered as an excel- lent product since it is homogeneous, has desirable esthetics, reduced level of contaminates, plant growth hormones, higher level of soil enzymes, and greater microbial population, and tends to hold more nutrients over a longer period without adversely impacting the environment. Earthworms while ingest organic waste and soil, consume heavy metals through their intestine as well as through their skin, wherefore concentrating heavy metals in their body (Hand et al. 1988; Logsdon 1994; Singh and Sharma 2002). A growing awareness of some of the adverse economic and environmental impacts of agrochemicals in crop production has stimulated greater interest in the utilization of organic amendments such as compost or vermicompost for crop production (Follet et al. 1981). Utilization of earthworms may be an answer as an ecologically sound, economically viable, and socially acceptable technology (Sharma et al. 2005). Vermicomposting as a principle originates from the fact that earthworms in the process of feeding fragment the substrate thereby increasing its surface area for further microbial colonization (Chan and Griffiths 1988). During this process, the important plant nutrients such as nitrogen, potassium, phosphorus, and calcium J. Tajbakhsh and E.M. Goltapeh (*), Department of Environmental Engineering, Faculty of Environment, Tehran University, 14115-336 Tehran, Iran e-mail: emgoltapeh@modare.ac.ir, emgoltapeh@yahoo.com A. Varma Director General, Amity Institute of Microbial Technology (AIMT) Vice Chairman, Amity Science, Technology & Innovation Foundation (ASTIF) Amity University Uttar Pradesh E-3 Block, Fourth Floor, Sector 125, Noida, UP 201303, India A. Karaca (ed.), Biology of Earthworms, Soil Biology 24, DOI 10.1007/978-3-642-14636-7_13, # Springer-Verlag Berlin Heidelberg 2011 215