Agriculture Reference
In-Depth Information
TABLE 19.2
Range of Nutrients in Vermicompost
Organic carbon (%)
9.15Ï17.98
Total nitrogen (%)
0.50Ï1.50
Available phosphorus (%)
0.10Ï0.30
Available potassium (%)
0.15Ï0.56
Available sodium (%)
0.06Ï0.30
Calcium and magnesium (meq/100 g)
22.67Ï47.60
Copper (ppm)
2.00Ï9.50
Iron (ppm)
2.00Ï9.30
Zinc (ppm)
5.70Ï11.50
Available sulfur (ppm)
128.00Ï548.00
material 30 cm apart. After 2 weeks, earthworms were released into the vermicompost pits through
temporary holes made on the mudpack. By this method, moisture loss from the waste was mini-
mized. Thus, the light and oxygen kept the earthworms active beneath the surface of the mudpack
in the organic wastes. This increases the biomass of the earthworms and the nutrient status of the
compost produced in a short interval of time (Table 19.2). The species
E. eugeniae, E. fetida,
and
P. excavatus
, which needs a
soil base, failed to survive. The large body size and low population-carrying capacity of
all work well under these conditions, whereas
Dichogaster curgensis
E. eugeniae
, which tolerates high population density pressure in its use for
urban solid organic wastes. Neuhauser et al. (1979, 1980) showed the sensitivity of
led us to depend more on
E. fetida
E. eugeniae
to
population density pressure. The carrying capacity of
on organic wastes under labo-
ratory conditions was studied and was measured as 0.015 g/cc (Kale and Bano 1991).
E. eugeniae
URBAN SOLID ORGANIC WASTE MANAGEMENT
The practice of waste segregation in India is growing both at the community level and in individual
households. The organic wastes are segregated in the home before handing over to garbage collec-
tors. Only the compostable waste is dumped into pits, constructed in public parks of residential
areas, for vermicomposting. The pits are covered with metallic mesh to keep away predators. A
low level and sloped roofs protect the pits from inundation during heavy rains and from direct
sunshine. Care is taken to maintain the aesthetic look of the parks while constructing the pits.
Similar vermicomposting activities are done in houses in small tubs or even in knitted sacks.
The daily garbage production in Bangalore (Karnataka) averages 2000 tons. In residential
localities, 70 to 80% of the solid waste is biodegradable organic waste.
Table 19.3
provides
information on the composting of such urban wastes in a residential area. The organic matter can
result in air pollution and groundwater pollution, both recognizable by the obnoxious odors, at the
dump sites and by released leachates. As an alternative, by collecting the organic wastes into
impermeable pits under aerobic conditions with selected species of earthworms, the entire material
is converted in a short time into good vermicomposts. The organic wastes that cause pollution and
are a source of epidemiological problems now become a source of income for those people who
have begun vermicomposting, and this vermicompost provides a high nutrient source that is very
beneficial to plants and evokes biological activity in impoverished soils.
The Karnataka Compost Development Corporation (KCDC), in association with Bangalore
City Municipality, is converting a portion of the city garbage into vermicompost (150 to 200
tons/day) and the same amount of garbage into enriched compost. They have a clientele convinced
about the high quality of the product. Their success has made them consultants to municipalities
of other states in the country.
