Effects of slope and aspects on soil properties, leaf nutrient status, and oil palm yield in a plantation in Selangor, Malaysia

• Auteur principal: Abdalrahem, Omar Mohamed Lbrahim
• Format: Thèse
• Langue: anglais
• Publié: 2022
• Sujets: Oil palm - Malaysia; Soil fertility - Malaysia; Slopes (Soils) - Malaysia
• Accès en ligne: http://psasir.upm.edu.my/id/eprint/121014/1/121014.pdf

Oil palm is an important crop in Malaysia that has contributed significantly to the country's economy. However, with limited land for oil palm cultivation, Malaysia has moved to convert marginal areas, including hilly and sloping land, into plantations. This can lead to soil erosion in these areas, resulting in loss of nutrients and water through runoff, reducing soil fertility and negatively affecting oil palm growth and production. There is limited research on how slope and aspect affect soil fertility and oil palm yields. Therefore, this study aimed to determine the relationship between slope, aspect and soil depth, properties and leaf nutrient and their effect on yield productivity in oil palm plantations. The study took place at FELDA Gedangsa plantations in Selangor, and data were collected on two slopes: one facing north and one facing south. Each slope was divided into three observation plots based on topography: the lower, middle, and upper slope positions. Soil samples were collected from the upper, middle, and lower slope positions at two depths: surface (0-20 cm) and subsurface (20-40 cm). Leaf tissue samples were also collected according to a systematic sampling design. Statistical analysis was performed using ANOVA and a post hoc comparison test with a 95% confidence interval to evaluate differences between soil indicators of different land use types. A paired-sample T-test was used to evaluate the differences in TN, pH, EC, soil texture, P, K, Ca, and Mg between the two soil depths and the two aspects. The results showed no significant difference (P<0.05) among the soil's physical properties and slope positions between the north and south aspects, the pH level was acidic in both aspects. The statistical analysis revealed a significant difference (P<0.05) among the soil properties in different slope positions and soil depths. Slope position significantly affected (p<0.05) all soil properties studied. Soil depth had a significant effect (p<0.05) on soil P, exchangeable Mg and Ca. And on the contrary, exchangeable K content was significantly different in the subsoil. Leaf nutrient contents varied, with nitrogen and Mg, rated as optimum, and K, Ca, and P rated as excess. Fresh fruit bunch (FFB) yield was highest at the base of the slope and lowest at the top at both study sites. Statistical analysis indicated a relationship between FFB and nutrients in the soil and leaf tissues, and there was no significant difference (P<0.05) between FFB and the aspect.