Agriculture Reference
In-Depth Information
supplied about 50 kgNha
1
per month and acted as fertilizer to the control
treatment.
C
ONCLUSIONS AND
R
ECOMMENDATIONS
Farmers were aware of the potential benefits compost could give to
improving soil quality, increasing yields and controlling the incidence of pests
and diseases. However, there were many concerns regarding the potential
costs of producing compost, the diculty in using the bulky compost and the
health risks associated with handling compost made from night soil.
WTP for compost was lowest for urban vegetable farmers (US$0.10 per
50 kg), who rely on readily accessible and cheap poultry manure, whereas
peri-urban vegetable farmers were ready to pay US$3 per 50 kg.
Demand for compost in Kumasi was estimated at about 11,000 tonnes per
year based on the assumption that subsidies were provided. But without
subsidies actual demand was only 940 tonnes per year.
Adding compost increased growth and did not delay germination of a
wide range of vegetables when applied at concentrations between 6.25 and
12.5 per cent, with the exception of carrot and onion. Nematode damage in
lettuce and tomato plants was also suppressed, and poultry manure was the
organic fertilizer of choice for the urban farmers in Kumasi.
In conclusion, we can infer from this study that large-scale compost
production from urban organic waste and night soil in Kumasi is not an
economically viable project without some kind of subsidy. Sorting and
transportation costs for compost at this scale outweigh the economic benefits
associated with the use of compost. There is a need to explore also the
viability of community-based composting initiatives at the farm level, where
sorting and transportation costs are minimal.
A
CKNOWLEDGEMENTS
This research project benefited from the support and time of many
individuals and organizations. The authors would like to thank the generous
financial assistance of the International Development Research Centre (IDRC;
AGROPOLIS programme), the IWMI, Wageningen University and Kwame
Nkrumah University of Science and Technology (KNUST). The compost
plant was funded by the IDRC, the French Foreign Ministry, the Swiss
Federal Institute for Water and Sanitation in Developing Countries
(SANDEC) and the KMA. We would like to acknowledge the support, help
and guidance of Dr S. Fialor, Dr W. Blok, Prof. C. Quansah, Dr R. Awuah,
Mr K. Osei, Dr P. Drechsel, Mrs K. Dapaah and all the technicians,
labourers and farmers who helped us throughout this project. A special
mention to the head of the composting project, Dr C. Olefunke, for her
dedication to this project.
