Utilization of agricultural wastes in papua new guinea

Abstract

In Papua New Guinea large quantities of crop residues (228,494 Mg) and animal wastes (492,638 Mg) are available for conversion into fuel, fertilizer and feed. It is estimated that a total of 5303, 3384 and 7136 Mg of N, P and K are available from crop residues and animal wastes with an approximate fertilizer value (in kina) of K12,329,117 (approximately US$ 13 million). Fertilizer trials with root crops, legumes and cereals responded to application of wastes and the percentage increase in yield over the control treatment ranged from 6 to 247% and the application rate at which maximum yield was obtained was different for different crops. Pyrethrum mare, evaluated for its feed value in sheep, has indicated its potential nutritive value as medium-quality forage for ruminants. The following recommendations are suggested: (1) research on the development of an integrated system to utilize waste for pollution control, livestock production and food production for both large and small holdings; (2) utilization of wastes for developing high-protein sources for human and livestock; utilization of coffee, cocoa and oil palm waste for mushroom production; (3) development and testing of simple, cheap and adaptable equipment for small farms for biogas and direct combustion for drying agricultural products; (4) residual and toxic effects from crop residues should be evaluated, e.g. continuous feeding of animals with coffee pulp and pyrethrum mare and its effect on the physiology in animals; and (5) studies combining composted wastes and inorganic fertilizers should be evaluated for mixed and plantation cropping systems.