Authors: K Upadhaya H N Pandey P S Law R S Tripathi
Publish Date: 2005/01/14
Volume: 41, Issue: 3, Pages: 144-152
Abstract
The present study was carried out to understand whether fine root growth and N mineralization are synchronized in such a manner that helps to conserve N in the humid subtropical forest ecosystem and to assess whether or not these processes are influenced by human disturbance The study was conducted in two pairs of undisturbed and disturbed stands of subtropical humid forest in the Jaintia hill district of Meghalaya northeast India The amount of fine root 540–754 g m−2 and coarse root 307–387 g m−2 mass in the protected stands was higher than those recorded fine root 422–466 g m−2 coarse root 247–305 g m−2 in the unprotected stands The total annual root production was also higher in the protected stands 1102–1242 g m−2 than the unprotected stands 890–940 g m−2 The mean concentration of NH4+–N and NO3−–N was higher in the protected stands than in the unprotected stands The inorganicN NH4+–N and NO3−–N concentration was markedly high during the dry period and low during the wet period in all the stands InorganicN concentration nitrification and N mineralization rates were significantly P001 higher in the surface 0–10 cm than the subsurface 10–20 cm layer The low and high N mineralization rates observed during the dry and wet periods respectively coincided with the lean and peak periods of fine root mass Disturbance in the forests caused a reduction in fine root mass as well as in N mineralizationThe authors thank the Ministry of Environment and Forests Government of India New Delhi for financial assistance in the form of a research project sanction no 14/28/95RE and the Dolloi of Raliang and Headman of Ialong for granting us permission to work in these forests The authors also thank two anonymous referees for their helpful comments which improved the manuscript
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