The Forest Resource Assessment (FRA) is an essential component of forest management planning that involves the collection of data about forest dynamics at the FMU level. This is conducted through the establishment of sampling unit (SU) in the production area of the FMU as per Forest Department Sarawak “Technical Manual For Forest Resources Assessment (FRA) in Sarawak” (FDS, 2019).  

The objective of the FRA is to determine the dynamic, quantity and quality of timber species in the production forest, at pre-determined levels of statistical accuracy and probability, and to provide a quantitative resource database for the determination of the Annual Allowable Cut (AAC) in natural forests.

Raplex FMU has completed the assessment of 65 Sampling Units (SUs) in 2018-2020 and is a direct output of the FRA Data Analyser Software (Overview Sheet), which is a program developed by IFMC.

The summary of FRA Results (from 65 SUs) as follows;

  • an average of 1,060 trees per hectare
  • average DBH equals 13.24 cm
  • average commercial bole height (CBH) and total height (TH) of 6.58 m and 9.32 m, respectively
  • mean stand basal area of living trees is 21.37 m2/ha
  • total volume averages 169.64 m3/ha, out of which 63.3% is commercial species.
  • 2% of the trees assessed during the FRA belong to protected tree species.

Permanent Sample Plots (PSP) network is very important to provide dynamic and reliable data on forest stocking and volume over time and under different forest condition concerning the impact of logging. For preliminary PSPs by Pinnacle Forest Solutions, 60 locations for the establishment of the PSPs were generated based on the computerized stratified random sampling to cover the canopy stand class as derived from the interpretation of the satellite imageries for each coupe. Only 32 plots were selected as PSP which distributed in Coupe 1,7,9,12,13,14,15,16,17,18,19 and 20.

For PSPs establishment at the FMU level, the selection of the PSPs was made from a sub sample of the SUs established during the FRA. The selection of the PSP from the FRA SU was carried out using the Ranked Set Sampling (RSS) method and this method has recommended 22 PSPs to be established.

Forest zoning is defined as the zoning of an FMU area into various forest functions based on the topography and land use patterns.  It is broadly zone into three key forest function zone namely Production – the total nest area that can be harvested for timber, Protection – to be left untouched during harvesting operation for conservation and protection purposes, and Community use –reserved for local community use such as shifting agriculture (SA) area, fruits orchards, vegetable farm, cultural site etc.  These areas are to be left untouched during timber harvesting operations.