Soil conservation by vegetative systems in oil palm cultivation

Abstract

In Indonesia, agricultural land for oil palm plantation is mostly placed on slope areas. Erosion carries down surface soil layers which are generally fertile and rich in organic matter and nutrients, causing the loss of plant nutrients. Cover crops provide protection against the destruction of soil aggregates by rain and runoff. This research aims to study the effectiveness of vegetation as soil conservation in controlling erosion and runoff. This study was a field experiment on erosion plots of 10 m × 5 m with 1–2-year-old oil palm trees planted on a 15–40% slope, which were arranged in a Split Plot Design with replications as blocks, consisting of a combination of two factors: the age of the oil palm and slope as the first factor, and conservation techniques as a second factor. The results showed that the soil conservation techniques in oil palm cultivation could reduce the rate of surface runoff, soil erosion and nutrient loss. Soil conservation with upland rice – soybean – Mucuna bracteata, in sequence (T3) in oil palm 7–25 months old and 15–25% slopes (P1) were most effective reduced runoff, increase the infiltration and preventing soil erosion and nutrient loss in all age of oil palm and slope of land.