Knowing the hill forest on the west slopes of Gunung Palung from
my thesis research at the Cabang Panti Research Station many
years ago, I have been looking forward to seeking differences in
tree composition in this valley. Most of the valley’s forest
occurs on ridges and slopes of granite-derived sandy soils (see
this paper by Chuck Cannon & Mark Leighton). However, around our
camp there is also some lovely, flat alluvial forest, at an
elevation of 230 meters. An area of very hard rock (a basalt
dike?) underlies the valley a half kilometer downstream from our
campsite, creating a high waterfall called Riam Parit. This
block seems to have ‘dammed’ the erosional deposits in the
valley above, creating a surprisingly large area of flat,
fertile alluvium. Low-elevation alluvial forests near the big
rivers of Borneo are the most diverse on the island and contain
the biggest trees, and are also the first to be converted to
agriculture. It will be interesting to see if this slightly
higher elevation alluvial forest,