Effect of sago palm (Metroxylon sagu Rottb.) cultivation on the chemical properties of soil and water in tropical peat soil ecosystem

Abstract

Tropical peatland is a potential land resource for crop production to supply food and energy sources to increasing population. Although sago palm (Metroxylon sagu Rottb.) is a potential starch crop suited to this purpose, prefer control of groundwater level and fertilizer application should be done to maintain the high starch productivity. As it is also important to estimate the impact of sago palm cultivation on the environment from the view point of the sustainability, we investigated temporal changes in the chemical properties of drainage water and soil in a sago palm plantation in Indonesia. Analysis of canal water from blocks with different palm ages during a 2-year period suggested small increases in Ca, K, and Mg concentrations with time (up to 8 years). No time-dependent changes were observed in the concentrations of other nutritional/toxic elements, although the larger concentration in groundwater below sago palm than in canal water was observed for fertilizer components including B, Ca, P, and Zn. Although large portions of Al, Fe, and Zn in canal water were interacted with dissolved organic C (DOC), the leaching of DOC did not vary with the development of palm growth. Contents of nutritional elements were generally similar among soils at 1, 3, and 5 m away from a palm, among soils at 0.1, 0.3, and 0.5 m depths, and between soils in sago palm block and adjacent secondary forest, regardless of plant age. Thus, the sago palm cultivation with fertilizer and groundwater level control did not induce notable deterioration of soil and water qualities.