Keywords :
Deciduous dipterocarp forest, Mortality rate, Population size structure, Recruitment rate, Stand half-life, Sakaerat
บทคัดย่อ :
Deciduous dipterocarp forest in the long-term dynamic studying plots in Sakaerat Biosphere Reserves (SDDF) demonstrates the slightly size structural changes by showing the relatively stable annual and mean values of size structure (expressed by the number of tree distribution by DBH class) and well fitted to the negative exponential function model in the 4 stands and in the whole forest over the period of 16 years. Tree population in the 4 stands representing different dominant tree species is in the state of continuing population flux by maintaining the continuous changes in tree mortality and recruitment throughout the period of 16 years. On the community level, mortality of trees in all 4 stands is surpassed by tree recruitment resulting in tree population gain in all 4 investigated stands. Mean annual tree mortality and recruitment fluctuate over the period of 16 years, varying between 70-134 trees.ha-1 of mortality and 71-259 trees.ha-1 of recruitment as averaged from the 4 periods of each 4-year interval. Over the whole 16 years period, there are significant differences of mean number of tree mortality and recruitment among stands, being greatest in stand 3, lowest in stand 4 and intermediate in other two stands. Estimated mortality and recruitment rates for the SDDF are in the range of 3.14-6.58 %.y-1 and 3.18-9.54 %.y-1 respectively, being most rapid rates in stand 3, slowest in stand 4 and intermediate in other two stands. Estimated mean stand half-life is 14.7 years although each stand has different stand half-life, being shortest in stand 3 and longest in stand 4, but slightly shorter than some published records of the investigated moist tropical forests.
เอกสารอ้างอิง :
Sahunalu, P. (2010a). Dynamics of size structure and tree population over 16 years in the long-term dynamics plot of Sakaerat deciduous dipterocarp forest, Northeastern, Thailand. Journal of Forest Management, 4(7), 19-32.
