Tuesday, October 10, 2006

Growth And Biomass Accumulation Of Some Early Successional Woody Species In An Uprooted Rubber Field At Kamburupitiya

H. K. P. Jayasekera and R. Senaratne
Department of Crop Science, Faculty of Agriculture,
University of Ruhuna, Mapalana Kamburupitiya.

A study was conducted on a successional vegetation in an abandoned uprooted rubber field at Kamburupitiya in 1999. It involved determination of growth parameters such as height, girth, biomass accumulation and partitioning of dry matter in three most widely occurring early successional woody species, namely Macaranga peltata, Alstonia scholaris and Trema orientalis of varying ages (3. 5 and 7 years). Here three trees of each species were sampled except A. scholaris where only 3 and 5 year old trees were sampled for each age class from each succeessional stand.

Growth parameters (height, gbh and rate of height and diameter), growth of all three species at 3, 5 and 7 years and the partitioning of dry matter to the leaves were compared among the three tree species and the ages sampled. According to the results obtained A. scholaris showed the highest absolute and relative stem elongation followed by M. peltata and then T. orientalis. However it recorded the lowest rate of increment in girth. At three years of age more dry matter is being partitioned to leaves and as the age progressed this proportion is significantly reduced in all the tree species sampled.

The implications of inter-specific variations in growth attributes and accumulation and partition of dry matter on nutrient conservation and restoration of disturbed agro-ecosystems are discussed.

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