(best examples and good practices) on household organic waste ...

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degraded, resulting in a final product containing stabilized carbon, nitrogen
<strong>and</strong> other nutrients in the organic fraction, the stability depending on the
compost maturity (Golueke et al., 1955; Diaz et al., 1993).
Composting reduces both the volume <strong>and</strong> mass of the raw materials while
transforming them into a stable organic final product which can be used as soil
conditioner <strong>and</strong> improver. Composting can occur at a rapid rate when optimum
conditions that encourage the growth of micro-organisms are established <strong>and</strong>
maintained. As mentioned composting is a controlled aerobic biological
decomposition of most organic solid matter <strong>and</strong> that differentiates the process
from the natural occurring decomposition. Nevertheless, the biochemical
process in composting <strong>and</strong> in the natural decomposition of the organic matter
is the same.
Composting process is mainly carried out by 6 groups of microorganisms :(1)
fungi, (2) actinomycetes, (3) bacteria, (4) worms, (5) protozoa, (6) larvae, etc.
The bacteria include a wide spectrum of classes, families, genera, <strong>and</strong> species.
For example, pseudomonades have been isolated <strong>and</strong> classified down to the
genus level. Although actinomycetes are bacteria, they are named separately
because of their particular role in the curing stage of the process (Golueke et
al., 1955).
Two genera of actinomycetes have been isolated <strong>and</strong> identified; Actinomyces
<strong>and</strong> Streptomyces (Golueke et al., 1955).The fungi rival the bacteria in terms of
number <strong>and</strong> importance in the later stages of the process. The worms include
nematodes <strong>and</strong> some earthworms (species of annelids).The larvae are of various
types of flies.
Attempts for a hierarchy identification of microbes down to the species level on
the basis of population <strong>and</strong> activity in the entire compost process had no
success until now, because of the inevitable local differences in the gamut of
environmental <strong>and</strong> operational situations. However, the following very broad
generalizations have proven to be adequate for routine composting, particularly
of MSW. In terms of number <strong>and</strong> activity, the predominant organisms are
bacteria <strong>and</strong> fungi <strong>and</strong>, to a far lesser extent, protozoa. However, earthworms
<strong>and</strong> various larvae may appear in the later stages of the composting process.
A fact which is referred as practical <strong>and</strong> important to the economy, is the
presence of these organisms which is a characteristic of all wastes—particularly