Abstract
Nine stands ranging in age from 1 to 22 years were selected to study dry matter and nutrient contents of the above-ground portion of Pinus kesiya. Allometric correlations were established by taking three independent variables (dbh, h and (dbh) 2· h) with different dependent variables (stem, live and dead branches, needles, cones, and total weight). Biomass data were used to estimate the primary productivity of the stands and also the net assimilation rates. With increasing stand age, the dry matter allocation was found to be more towards the bole portion; correspondingly, the allocation towards needle production decreased. Mean annual productivity was found to increase with the age of the stand. However, net primary productivity reached a peak in 5–7-year-old stand after which there was a decline in older plantations. Higher biomass and productivity of this species was comparable with that reported for high-productivity species like P. caribaea in Malaysia and P. radiata in New Zealand. The high productivity of P. kesiya could be accounted as due to high net assimilation rate of needles due to prolonged photosynthetic activity produced in three flushes during the year. The concentration of nutrients (N, P, K, Ca and Mg) decreased in the following order: needles > live branches > dead branches > boles > cones. The concentration showed a decreasing trend with increase in tree age for all nutrient excepting Ca which showed a reverse trend. Stand nutrient contents were predominantly in the order of N > K > Ca > Mg > P.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.