Litterfall, decomposition and nutrient release patterns of different tree species in Taran Taran district of Punjab, India

Abstract

The present investigation was attempted to assess the leaf litter production, decomposition rate and amount of major nutrient return in Populus deltoides, Eucalyptus tereticornis, Tectona grandis and Pyrus pyrifolia based agroforestry land use systems in Taran Taran district which falls in the north western agro-climatic zone of thePunjab state, India. The litter production in selected tree species was quantified using litter traps and decomposition pattern of leaf litter was investigated by litter bag technique. Litterfall in the selected tree species varied significantly (5 % level of significance) during different months of the study period. Among the four species, P. deltoides exhibited highest leaf litter production (7.8 tons/ha) followed by T. grandis (1.83 tons/ha) and E. tereticornis (1.77 tons/ha) whereas, lowest leaf litter production was observed in P. pyrifolia (0.34 tons/ha). The present study also showed that temperature as compared to rainfall play a significant (5 % level of significance) role in litter decomposition. In case of P. pyrifolia, P. deltoides and T. grandis decomposition take place 100 per cent, 98 per cent and 99 per cent respectively after 10 months whereas in E. tereticornis 87.7 per cent leaf decomposed after 10 months. The nutrients percentage through litter fall was maximum of nitrogen (2.27 %) followed by potassium (1.90 %) and phosphorous (0.32 %). Maximum and minimum N input through leaf litter was in P. deltoides (2.27 %) and P. pyrifolia (1.15 %). The K input (%) was maximum in leaves of T. grandis (0.32) and minimum in E. tereticornis (0.21). The maximum input of P (%) through leaf litter was in P. deltoides (1.90) whereas, minimum value was observed in E. tereticornis (1.27). Tree based agroforestry land use systems improve soil nutrient status as compared to traditional wheat and paddy based land use systems under this region of Punjab. Therefore tree based land use systems need to be promoted over the traditional field crops for realizing better environmental benefits in this region.