900| Biolife | 2014 | Vol 2 | Issue 3 B I O L I F E R E S E A R C H A R T I C L E LEAF LITTER DECOMPOSITIONAL PATTERN IN A TROPICAL LAKE OF SOUTH INDIA Anbalagan, S 1* , Rameshkumar, N 2 , Balachandran, C 3 , Arun prasanna, V 4 , Dinakaran, S 5 and Krishnan, M 6 1,4,6 Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli-620 024, Tamil Nadu, India 3,5 Department of Zoology, The Madura College, Madurai-625011 Tamil Nadu, India E-mail: anbumdu@gmail.com ABSTRACT The effects of leaf toughness and C/N ratio on decomposition rates of three riparian plants were examined using a litter bag assay of three litter types (soft, medium and hard) during 35 days exposure at the unpolluted tropical lake of India. Decomposition rate was affected by both litter type and chemistry. However, litter types accounted for the most variation in decomposition rates. Soft litter type decomposed more quickly than medium and hard litter types. The time taken for 50% weight loss of hard, medium and soft litter types would 20 days, 18 days and 1 day, respectively. The C/N ratio was decreased in hard and medium litter types and increased in soft litter type. Key Words: Decomposition, C/N ratio, leaf litter, litter type. INTRODUCTION Leaf litter from riparian plants provides an important source of nutrients, energy and shelter in freshwater ecosystems (Henderson and Walker, 1986; Wallace et al., 1997). Leaf litter decomposition is a complex process that is regulated by physical, chemical, and biological processes. The rate of decomposition has been related to the chemical quality of the litter and to the environmental conditions where the process occurs (Webster and Benfield, 1986). The litter- bag assay (Boulton and Boon, 1991) is the most common approach for evaluating litter decomposition in the field and involves enclosing a known mass of plant litter in mesh bags, incubating them in the field, and later retrieving the litter bags to determine the amount of litter that has decomposed over time. The litter-bag assay has done much to advance understanding of organic-matter decomposition, nutrient cycling, carbon storage, and detrital food webs (Tiegs et al., 2009; Imberger et al., 2010). Several studies on litter decomposition related to litter types, chemistry, assimilation and colonization of macroinvertebrates have been carried out in streams of temperate and tropical regions (Cortes et al., 1997; Pettit et al., 2012; Tiegs et al., 2013). Few such studies have done in India, especially streams that leaf litter retention, transport, decomposition and colonization of macroinvertebrates (Krishnankutty et al., 2003; Anbalagan et al., 2012a, b; Sridhar et al., 2013). Recently, breakdown of leaves and macro-invertebrate colonization in an a static pond was studied in South India (Dinakaran et al., 2008) and no other AN INTERNATIONAL QUARTERLY JOURNAL OF BIOLOGY & LIFE SCIENCES 2(3):900-904 ISSN (online): 2320-4257 www.biolifejournal.com