ON-FARM QUANTIFICATION AND USE ASSESSMENT OF ORGANIC RESIDUE IN TAMALE

Abstract

Agricultural field residues constitute a major part of the total annual production of biomass and the residues are an important source of soil organic matter. Crop residue play an important role in nutrient recycling, erosion control and maintenance of favourable soil physical properties. Crop residue has the potential of increasing biological activities through temperature moderation as left-over crops after harvest covers soil surface. To address this, a field survey was conducted in the Tamale Metropolis in 2015 on the quantification and assessment of uses organic residues. The objective of the study was to determine spatial and temporal availability of organic materials for compost, biochar production and animal fodder or direct field application in urban and peri-urban areas of Tamale. Study was carried out in 31 communities within Tamale and its environs and under the three production systems namely backyard, open space and village farms. Crops residues studied include maize, rice, groundnuts and soy. Structured questionnaire and interviews were employed to collect information from 95 farmers in the study area aided using geographic information system (GrS) technology applied in the identification of respondents. Random sampling was used on 67 percent of the sample whiles 33 percent was purposive sampling techniques were applied in the study. Quantification was also done on all 95 respondents by using dry weight of the selected crop residues obtained from the fields. The results show high residue generation on rice (1481.41 kg per acre). This was followed by soy (784.20 kg per acre), maize (115.22 kg per acre) and groundnuts (80 kg per acre) respectively.Residues of the various crops selected were found to be available all year round except rice. But large quantities were available in November through to December when harvesting and processing had just been completed. The cost of obtaining residue for re use was high on rice (GHC92.78.00/ac) followed by maize (GHC24.2/ac), soy (GHC 24.09/ac) and least for groundnuts (GHC 11.7/ac). Creation of fire belts, gathering of crop residues and transportation are the main cost items incurred in obtaining the residues for re-use. It was also found that manure was used more across the three production system for maize (backyard, open space and village farms) with the highest recorded on the village farms (318.21 kg/acre). However, the use of compost was the least patronized soil amendment practice by local farmers due to inadequate knowledge in the preparation and time involved to prepare them.