Study area, materials and methods
The study was conducted in and around Accra, Kumasi,
and Tamale, each located in a different agro-ecological
zone in Ghana. Accra, the capital, is located in the
coastal-savanna zone with about 1.6 million inhabitants.
The population growth rate of Accra is approximately
3.4% per annum in the city itself but up to 10% in its
peri-urban districts. Kumasi is located in the humid forest
zone and has a population of about 1 million and an
annual growth rate of 6%. Tamale is in the northern
savanna zone and has a population of 200,000 with a com-
paratively low growth rate of 2.5% (Ghana Statistical Ser-
vices, 2002). The cities were selected because of their
differences in cultural, social, economic and eco-zonal char-
acteristics. These characteristics are expected to affect, for
example, the availability and use of organic biomass and
the related demand for compost