Author : Sar Rao

Summary : A case study on logging damage was made in the Colexim forest concession. the study area lies in Kompong Thom Province in the central part of Cambodia. It consists of flat terrain covered by tropical rainforest dominated by dipterocarp species. Logging followed the guidelines of the Cambodian selective cutting system and took place in 1997. The field investigations were made in 1998. The disturbance of the soil surface and the damage of the remaining stand with diameters above 10 cm at breast height were investigated in six sample plots of 100 X 100 m, divided into two per high, medium and low looging intensities which were defined by the percentage of the basal area removed. The damage to the natural regeneration (saplings between diameters of 5 and 10 cm as well as between diameters of 1.5 and 5 cm and seedlings up to a height of 1.5 m) were studied on sub-plots of 10 X 10 m, 5 X 5 m and 2 X 2 m. The damage to the remaining stand increased from 10% to 19% of the total basal area when the basal area harvested increased from 13 to 35% of the total basal area. These differences, however, only indicate a tendency because their statistical significance could not be proved due to the small number of sample plots per logging intensity. The most frequent cause of damage was felling followed by causes which could not be clearly defined and then by skidding. This indicates that even better results might be reached if the felling operations could be improved. Other improvements lie in a strict application of the principles of the Cambodian selective cutting system. In general, the study demonstrated that the disturbance of the soil surface and the damage to the remaining stand as well as to natural regeneration reached favorable levels. This was the result of a limited number of trees harvested, the use of small scale equipment for skidding and the restriction of skidding to as few trials as possible.