Litter production and leaf-litter decomposition of selected tree species in tropical forests at Kodayar in the Western Ghats, India

Litter production, standing crop of litter on forest floor and leaf-litter decomposition of selected dominant tree species were studied in the tropical forests at Kodayar in the Western Chats, India. Mean annual litterfall in the study sites ranged from 5.63 to 8.65 Mg ha(-1) year(-1). A greater amount of annual Litter production was observed in sites II and III, when compared to sites I and IV. This variation in litterfall pattern among the sites could be attributed to species composition. Monthly variation in Litterfall pattern showed two peaks, one in the dry season (January-April) and another in November. Contribution of leaf litter to the total litter was significantly (p < 0.01) greater compared to other components (woody litter and reproductive parts). In deciduous forests, Terminalia contributed significantly (p < 0.05) greater amount of leaf litter to annual litter production, followed by Careya arborea, Macaranga peltata, Aporosa lindleyana and Dillenia pentagyna, whereas in evergreen forests, Hopea parviflora contributed the most. The results suggest that species composition and their contribution toward litter becomes important in overall community or site litter production as observed in sites II and III. The litter mass decreased linearly with time. Thin and smooth leaf without prominent skeletal tissues decomposed more rapidly, while thick and tough leaves with prominent midribs and veins took longer time for complete decomposition. The species with high nitrogen content exhibited relatively faster decomposition except in H. parviflora and V. indica. The differences in decay rates and half-life periods are related to structure and nutrient concentration of leaf litter and the environmental factors. (C) 1999 Elsevier Science B.V. All rights reserved.