BIOMASS AND NUTRIENT ACCUMULATION IN Prunus arborea (Blume) Kalkman (ANGIOSPERMS: ROSACEAE) OF DIFFERENT AGES
HOANG VAN THANG *
Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
CAO VAN LANG
Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
HOANG VAN THANH
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
VU VAN DINH
Forest Protection Research Centre, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
NGUYEN TRONG DIEN
Phuc Yen Town, Vinh Phuc, Vietnam.
TRAN VAN DO
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
*Author to whom correspondence should be addressed.
Abstract
Understanding nutrient content and biomass accumulation is important for fertilization schemes, harvesting management, and sustainable plantation management to meet demands on timber and fuel. In this study, biomass and nutrient accumulations were studied for Prunus arborea trees of 1- to 5-years old. Medium-sized trees were sampled to collect biomass and representative samples were collected for nutrient (N/nitrogen, P/phosphorous, and K/potassium) analysis. The results indicated that power function was best fitted for a relationship between age and dry biomass of individual trees. While the polynomial pattern was best fitted for the relationship between ages and ratios of below- to above-ground biomasses with the lowest ratio of 21% in trees of between 3- and 4-years old. Among the four analyzed organs, N, P and K contents were highest in leaves and lowest in the stem. While that in branches and roots were similar. In leaves, N and K contents were 0.4–1.48%, while P contents were 0.10–0.36%. In stems, N and K contents were 0.15–0.61%, while P contents were 0.01–0.21%. It is concluded that low P contents may indicate the P deficiency in the site, leading to fertilization requirements. While N and K application may not be necessary. Remaining leaves in the site at logging may partly compensate soil nutrients from high leaf biomass (up to 26% total biomass) and the highest nutrient contents (up to 1.48%).
Keywords: Biomass, nutrients, plantation, tree ages, tree organs