USE OF COIR DUST ON THE PRODUCTIVITY OF COCONUT ON SANDY SOILS

Abstract

Sandy soils in the coconut triangle often impose limitations such aspoor nutrient retention and moisture availability on the growth of the coconutpalm. The physical properties of such soils has to be improved for increasingcoconut production. Incorporation of coir dust into soils, which isan organic waste of coconut fibre industry is one of the options. A series oflaboratory experiments were conducted to evaluate the capability of coirdust of different age to retain water and nutrient and to investigate the suitablemixing ratio of coir dust and soil to ameliorate the moisture status andpore size distribution of the sandy soils. Soil physical characters of coir dust/sand mixtures such as pore size distribution, capillary rise, water retentionand reduction pattern of different ratio of coir dust and soil were determined.Chemical characteristics of coir dust were also determined to study its environmentalsustainability. Chemical characteristics showed that coir dusts arepoor in nutritional value but high in nutrient retention capacity and it is highlyresistant to environmental biodegradation. The available water capacity measuredin coir dust aged from 0 to 20 years indicated that the quantity of availablewater increased from 122.7% in fresh to 222.4% in 20 years old material (g/g). The increase in available water showed a linear trend with a age ofcoir dust (r=0.913; P