Abstract

The environment of young and mature oil palm plantation were found to be different due to the size of the oil palms and the depth of water tables applied. The environments in both sites have probably influenced the changes of peat soil physical properties towards the peat land degradation. A study was carried out to compare selected physical properties of deep peat between two different ages of oil palm plantation to determine the changes that occurred after the oil palm plantation has been established. This study was conducted by comparing selected peat soil physical properties of 2 and 10 years old oil palm plantations developed on 3 m depth of peat land which was classified as deep peat. A 300 m²experimental plot was designed in both sites. Comparison analysis showed that fiber content, loss on ignition, total porosity, liquid limit, surface soil temperature and bearing capacity were found greater in young oil palm plantation (YOPP) but volumetric water content, bulk density and ash content were found greater in mature oil palm plantation (MOPP). Meanwhile, gravimetric water content, specific gravity and saturated hydraulic conductivity were found statistically similar between the both sites.  The soil compaction and the reduction of organic matter content increased the bulk density and reduced the total porosity. Surface soil temperature and bearing capacity were decreased due to the closed condition and high water table, respectively in MOPP, whereas the change in saturated hydraulic conductivity was hardly determined due to the presence of partially decomposed residues in the peat soil of YOPP.

Key words: Deep peat soil physical properties, young and mature oil palm plantation.