Some important elements of soil-water relationship in managing oil palms planted on acid sulfate soils

Oil palms (Elaeis guineensis) are generally able to grow economically and feasibly on various soil types, mostly in tropical countries. However, oil palms planted on acid sulfate soils were producing lesser Fresh Fruit Bunches (FFB) as compared to those on non-acid sulfate soils. The poor performance of oil palms planted on acid sulfate was mainly attributed to the presence of excess sulfates, which limits the FFB yields and vegetative growth.1 Generally, acid sulfate soils have significant amounts of free and absorbed sulfate. Jarosite generally occurs as pale yellow mottles along old root channels and on ped faces in acid sulfate soils. pH in these horizon is less than 4.0.2,3 These soils often are also high in Aluminium (Al), Al saturation and often with phosphorus (P) fixation capacity. These acid sulfate soils are known for having poor values for organic matter, bases, cation exchange capacity, water retention, water holding capacity and microbial activity, which contributes towards their low soil fertility and hence limitations in soil productivity. Of these limitations, Al toxicity and excess sulfates are two major constraints to FFB yields in oil palms. The important relationship of soil and water for managing a sustainable productivity of oil palms on acid sulfate soil are discussed in details in this paper.