Regeneration of fire degraded peatswamp forest in Berbak National ...

Regeneration of fire degraded peatswamp forest in Berbak National Park and implementation in replanting programmes
5. Results
5.1. Analysis of satellite imagenary and pre-selection of research locations
5.1.1. Landsat and HotSpot
The series of satellite images obtained from Landsat, provides a clear overview on distribution and
abundance of forest fires between 1983 and 2002 and the disturbances that took place before the
1997/98 fires. Giesen (2004) provides a detailed analysis of activities that affected Berbak before 1997
and their probable link with fire outbreaks. This report suffices with a short overview of major events
and some additional comments, based on the satellite images.
1. In the early 1980’s the park was still in a relatively pristine state (figure 5.3a). Although the
east and South side of the park were encroached upon by farmers and loggers (and affected by
fire in 1982) the 1983 satellite image indicates that the core zone and western part were still
unharmed. There were no signs of logging trails or clear-felling.
2. By 1989 the situation had changed (figure 5.3b). West of the park, just outside its borders,
fires had degraded small patches of forest. In the satellite image the slightly lighter green
colour of the core zone relative to its surroundings, might be an indication of human impact.
3. By 1992 forest fires also occurred within the park. Two sites situated at relatively deep peat
deposits along the upper reaches of Air Hitam Laut, were affected (figure 5.3c). On other
images large logging trails extending from the north-west of the park running towards Air
Hitam Laut River are clearly discernable.
4. Since then the situation progressively worsened. The 1997 image clearly indicates increased
human activities in the core zone (figure 5.3d) Several small fires already occurred along the
Air Hitam Laut, in the centre of the core zone that was later affected by the 1997/98 fires.
Clear-felling is visible in a square 120 to 150 ha site between Simpang Kubu and Simpang
Aro. During a short visit to the site no survivors or dead standing trees were observed and all
trees had presumably been cut. The reason for this practice remains unclear, but it seems
improbable that the site was felled for logging purposes. Reaching the site is only possible by
canoe and transport of logs out of the area would be very difficult due to large floating beds of
Hanguana malayana that block the river. Maybe the site had been used for agriculture,
although it seems not very suitable as it is deeply flooded in the wet season. The presence of
approximately 10 large huts along Simpang Kubu River, very close to the clear felled site
might support this theory (figure 5.2). The huts are dilapidated and some of them have
collapsed. Fishermen reported that more than thirty people lived in the camp. According to
them, the camp was inhabited for one year until the beginning of 2003, when the inhabitants
left the area because their fishing revenues collapsed. They reported to know nothing about the
clear-felled site. The fishermen’s statement might have been true, as the camp was clearly
used for fishing purposes. On the other hand the camp looks very old, and given the extent of
the settlement it is well possible that the inhabitants, if the camp was built earlier than the
fishermen suggested, collectively cleared the land for agriculture.
5. Several weeks after the image had been recorded, the 1997/98 fires destroyed more than ten
percents of the park. Sites that were degraded by logging were most severely affected and
there seems to be a direct link between logging and outbreak of fires. The results of the
1997/98 fires are visible in figure 5.3e. In subsequent years fires reoccurred in many burnt
sites mainly in the west of the core zone and along the upper reaches of the Air Hitam Laut
River (figure 5.3f,g and h). This pattern of reoccurrence was of importance for the selection of
the final survey locations.
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