Agriculture Reference
In-Depth Information
Economically; composting can be started with very little capital and operating
costs, it is easy to implement at different levels (household to large scale compost-
ing) and can generate greater income from the avoidance of methane emissions to
the substitution to agrochemicals (Hoornweg et al.
1999
).
Environmentally; composting allow the reduction of organic content within the
local disposal site, less greenhouse gases (GHG) emissions as compared to land-
filling, recovery of organic materials and production of soil enhancer/organic fertil-
izer, reduction of chemical fertilizer application within the municipality, reduction of
leachate production and potential ground and surface water pollution, odour, poten-
tial hazardous air emissions, visual intrusion and litter nuisance (Bogner et al.
2008
).
Socially; composting increases employment opportunities in the cities, inte-
grates additional livelihood opportunities, supports poorer farmers with bio-fertiliz-
ers supply, reduces health risks to the neighbouring communities and promotes the
awareness of the potential value of waste, which normally is perceived as odorous
und useless (Perla
1997
). Adding compost in tropical acidic or sandy soils may in-
crease water and nutrient holding capacity and storage; and also reduce soil acidity
and toxic metallic ions such as aluminium and manganese.
13.5.3
Factors Constraining Composting in Developing
Countries
Despite the numerous advantages of composting they are many constraints to the
development of this technology, obstacles that could be overcome. Municipal man-
agers first take into consideration the cost of any change in MSW management
policy, so when evaluating composting promotion programs, they first check the
cost of composting versus landfilling. Dumping or landfilling is inexpensive and
not subject to effective environmental controls, while composting is relatively ex-
pensive, therefore, the cost of composting should be competitive with the cost of
landfilling.
The biggest difficulty faced by most composting programmes in generating in-
come is finding a market for the compost; it is difficult to secure finances since the
revenues generated from the sale of compost rarely cover processing, transportation
and application costs, a suitable marketing plan for the produced is necessary. e.g.,
in Yaoundé/Cameroon, 700 t of municipal wastes are collected daily, and techni-
cally, 150-200 t of compost could be produced daily, so the main worry for any
centralized composting plant is to know how this compost could find a suitable
place in the city and in the surrounds. The raised concern about the cost of com-
post could find solution in the way that the end-users have to be located closer to
the composting plant; the solution should be many decentralized small compost-
ing plants, targeting specific farmers. Compost substrate for nurseries (horticulture,
fruit trees: cocoa, coffee, oil palm) of specific interest is the potential market of
integrating compost for increasing soil microbial activities and large scale produc-
tion of beneficial microorganisms such as nitrogen fixing bacteria and mycorrhizal
fungi inocula (Nwaga et al.
2012
).
