DATA ANALYSIS FROM DECOMPOSITION AND MINERALIZATION OF WEED BIOMASS EXPERIMENT IN COFFEE USING LITTER BAGS

Abstract

Increased understanding of surface residue decomposition and mineralization may improve ground cover management of coffee plantation growing under shade. The first function of ground covers in coffee plantations is to prevent soil erosion, the second function is to improve soil fertility through nutrient cycling, and the third one is to reduce the amount of chemical products to control the most competitive weeds. This experiment of weed biomass decomposition was carried out in rainy season of 2000, with the main goal of determine the rate of decomposition and nutrient (N, P, K, Ca and Mg) release pattern of leaves and stems for the most common weeds in coffee plantation of the pacific area of Nicaragua. Leaves and stems of the weeds were separated and oven-drying and 30 grams were placed in litterbags of 30 cm x 30 cm x 2.5 cm deep. Litterbags were placed on the bare soil surface in the inter-rows of coffee plants and were collected every 7, 14, 21, 35 and 56 days or depending of biomass lost. The most appropriate statistical analysis for decomposition was the double exponential decay model were occurred two decomposition rates (labile and recalcitrant), while nutrient release pattern were fitted by the asymptotic model. The 50% of biomass lost occurred during the first 14 days and more than 50% of nutrient release occurred during the first 7 days.

DOI: http://dx.doi.org/10.5377/calera.v13i21.1681