Nutrients Uptake and Cycling of Pineapple Planted on Tropical Peat

Abstract

The obectives of the study were: (i) To quantify the dry matter production and nutrients uptake under burnt and unburnt pineapple residue management practices, (ii) To determine the nutrients capacity and intensity of tropical peat under pineapple cultivation, (iii) To quantify the movement of nutrients in pineapple production system, and (iv) To conduct economic valuation of the burnt and unburnt pineapple residue management practices. Treatments used were: (i) Leaves residue removed and no fertilization, (ii) Leaves residue burnt and no fertilization, (iii) Leaves residue removed and fertilization, and (iv) Leaves residue burnt and fertilization. The experimental unit was individual plant planted in 4 m x 12 m plot. Altogether 300 pineapple plants were planted in this plot having a randomized complete block design (RCBD) with 4 replications. Phosphorus and K were applied in the fonns of China phosphate rock and muriate of potash at the rates of35.56 P and 556.56 K kglha. At maturity, 3 plants were sampled from each treatment and partitioned into roots, stem, leaves, fruit, crown and peduncle and their dry weight, P, K, Ca and Mg concentrations determined. Soil sampling at the depths of 0-5, 5-25 and > 25 cm was done before, during and after fertilization stages. Soil solution P, Ie, Ca and Mg􀄟 extractable P, K, Ca and Mg; and tota1 P, K, Ca and Mg were extracted using the squeeze, double acid and dry ashing methods, respectively. The subtraction method was used to estimate P, K, Ca and Mg leached. Average weight of fruit for the treatments i.e. leaves residue removed and fertilization and leaves residue burnt and fertilization were detennined from 100 fiuits. The weight multiplied by plant density gave total yield/ha. The product of the total yield/ha and farm-gate price gave the gross revenue of crop production. Cost of labour was based on the wage system practiced by the estate. Farm-gate market prices were used for farm materials and other inputs. Interest rate of 12% on capital was adopted. Polluter Pay Principle, the Malaysian Environmental Quality (Clean Air) Regulations, 1978 on burning of waste and Air Pollutant Index (API) were used to value pollution. Land Expectation Value (LEV) was used to compare the viability of the two practices.