%0 Journal Article
%T Life Cycle and Secondary Production of Four Species from Functional Feeding Groups in a Tropical Stream of South India
%A Sankarappan Anbalagan
%A Sundaram Dinakaran
%A Muthukalingan Krishnan
%J International Journal of Zoology
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/191059
%X This study focused on life strategies of species from functional feeding groups (FFGs) found in a tropical stream of the Sirumalai hills, South India. We examined the life cycle and secondary production of species of shredders (Lepidostoma nuburagangai), scrapers (Baetis sp.), collectors (Choroterpes alagarensis), and predators (Neoperla biseriata). In addition, we studied the assemblage structure of functional feeding groups. We found the collectors occupied the highest percentage, followed in turn by scrapers, predators, and shredders. The diversity of FFGs was higher at riffle areas and assemblage with stream substrates differing in each functional group. An asynchronous life cycle was observed for Baetis, C. alagarensis, and N. biseriata, while L. nuburagangai was found in four to five generations per year. We acquired data on secondary production of scraper species of Baetis, which reached the highest values among all investigated species. This observation stresses the importance of scrapers as playing a key role in converting coarse particulate organic matter to fine particulate organic matter with low or high abundances of shredder population and maintaining the food chain in tropical streams. 1. Introduction Tropical forests cover 15¨C20% of the earth¡¯s land surface and about half of this is being converted to agricultural land and for other human purposes. More than 50% of the world¡¯s biodiversity is found in the tropical forests. Freshwater ecosystems are relatively more important than the terrestrial ecosystems because aquatic organisms are highly susceptible to climatic variation and anthropogenic impact [1]. The allochthonous organic substrate provides protection and habitat space and it has fundamental importance as a food source for aquatic macroinvertebrates [2]. Aquatic macroinvertebrates are classified into four major functional feeding groups (FFGs) based on the morphobehavioural mechanisms of food acquisition rather than taxonomic groups as follows: shredders, scrapers, collectors, and predators [3]. Feeding measures that contribute to fluvial trophic dynamics encompass FFGs and provide information on the balance of feeding strategies (food acquisition and morphology) in the benthic assemblage [4]. The major food sources utilized by macroinvertebrates are the epilithic layer that grows on the surfaces of substrates (consumed by scrapers), the coarse detritus of leaves falling from riparian vegetation (consumed by shredders), the fine detritus either deposited on the substrate or suspended in the water column (consumed by
%U http://www.hindawi.com/journals/ijz/2014/191059/