DYNAMICS IN PHYSICOCHEMICAL PROPERTIES OF SOILS UNDER OIL PALM
PLANTATIONS OF DIFFERENT AGES
Abstract
Removing forest cover for oil palm plantations has raised questions
about climate change problems and debates and their associated impacts.
The design of the pruned fronds of the trees does not make them ideal
for use as mulch cover on the entire farm, but they are heaped between
the plant rows. This research investigated the changes in the
physicochemical properties of soils under oil palm plantations of
different ages. Soil surface (0-20 cm) and subsurface (20-40 cm) samples
have been obtained from various ages of oil palm plantations (0-5, 5-10,
10-15 and, 15-20 years). Two distinct samples were taken on the same
farm, under alleys and heaped pruned fronds. Soil samples used as a
standard (control) were collected from adjacent forest land. Analyses of
particle size showed that the soils were sandy loam to sandy clay loam
texture soils. Bulk density was low and varied with age and depth. The
soils were moderate to slightly acidic pH, relatively low organic
carbon, total nitrogen, and available phosphorus contents. Based on the
standard ratings, exchangeable bases and cation exchangeable capacity
content were also low, while high percent base saturation was observed.
Research findings have shown that the soil properties of different ages
of oil palm plantations vary and should therefore be handled differently
based on of their characteristics. Accumulation of organic residue on
the floor of the plantations should be encouraged as this will help to
increase organic matter levels.