Vermiculture means artificial rearing or cultivation of worms (Earthworms) and the technology is the scientific process of using them for the betterment of human beings. Vermicompost is the excreta of earthworm, which is rich in humus. Earthworms eat cow dung or farm yard manure along with other farm wastes and pass it through their body and in the process convert it into vermicompost. The municipal wastes; non-toxic solid and liquid waste of the industries and household garbage’s can also be converted into vermicompost in the same manner. Earthworms not only convert garbage into valuable manure but keep the environment healthy. Conversion of garbage by earthworms into compost and the multiplication of earthworms are simple process and can be easily handled by the farmers.
Organisms of the Vermicomposting
Bacteria, micro-organisms and earthworms participate in the vermicomposting process, of which bacteria and micro-organisms are used as food for worms. Throughout the world, 3 or 4 species are used in vermiculture but two species are used extensively in India. Eisenia foetida and Eudrilus eugeniae are used throughout India for vermiculture.
Classification of Earthworms
Based on the feeding habits, the earthworms are generally classified into detrivores and geophages. The detrivore earthworms feed mainly on plant litter, plan debris or mammalian dung. They collect the feed from the soil surface. These worms compose the epizeic forms.
The detrivorous earthworms are Eisenia foetida, Eudrilus eugeniae, Lampito mauritii, Polypheretima elongata, Octochaetona serrata, Octochaetona surensis, etc.
The geophagous earthworms live in underground burrows and eat large quanties of deeper organic rich soil which remains beneath the surface layer. These worms are called humus feeders. Pheretima posthuma and Octochaetona thurstoni are the examples of geophagous earthworms.
Process of Vermicomposting
It deals with the various aspects like:
- Types of container,
- Filling it with moist bedding
- Introducing worms and
- Feeding the worms on a regular basis.
These types of aspects for vermicomposting are practised in small scale vermicomposting but in larger scale the basic processes are same excepting the composting containers.
The shape or size of the containers depends upon the amount of waste to be composted and the number of earthworms which we want to culture
In 1m × 1m × 0.5 m high container 2000 adult earthworms can be maintained which can convert 200 kg wastes into composting material per month. In 2.23 sq. metre container 10 kg earthworms can be maintained which can convert about 1 ton waste per month. The selected container should be cleaned before use.
The followings are considered as composting materials which are being listed below:
(i) The animal dungs such as cattle dung, goat dung, sheep dung and poultry dropping are used as the composting material. The preliminary testing and precautions are necessary for the pathogens which can be harmful to earthworms excepting cowdung.
(ii) The agricultural waste materials which include the discarded part after harvesting and threshing of the paddy, wheat, etc. The vegetable wastes, leaf litter and sugarcane trash are considered as the composting material. The various kinds of forestry wastes, such as peels, saw dust are also considered. The leaf litters, such as mango, guava and grasses are used as composting materials.
(iii) The garbage includes various kinds of biodegradable and non-degradable materials. The biodegradable materials, such as kitchen vegetable waste, paper, should be sorted, recycled or composted.
At the bottom of the containor, a 2-3 inches thick layer of biodegradable matter, e.g., husk, grasses, stem of crops and sugar cane trash, etc. which are used as the feed of earthworms, is laid. Next to this layer, another layer of 2″-3″ thick of powdered cowdung is put.
The whole material is maintained moistened and required number, of live earthworms are released. Above this a 7″-9″ thick layer of earthworm feed matter is put and watered. The whole material is covered with a moist gunny bag.
The earthworms would multiply by consuming the food and compost the matter from upper layers. The upper layer of vermicompost becomes ready within 60-70 days. Gradually the whole matter will be converted into vermicompost within 30-40 days with the bacterial decomposition.
Feed Materials of Earthworms
Earthworms eat decomposed organic matters. So various kinds of food are prepared used in vermiculture.
- Old cow dung which is used after 7 days.
- Cow dung is mixed with kitchen wastes in the ratio of 10:3.
- Cow dung is mixed with agricultural wastes in the ratio of 10:3.
Advantages of vermiculture
- Earthworms leave soil 5 to 11 percent richer in the essential plant nutrients of nitrogen, phosphorus and potassium than when they first ingest it. As an organic fertilizer, vermicompost is a substitute for synthetic fertilizer in soil-enriched vegetable transplant potting mixes. As a soil conditioner, vermicompost is superior to traditional compost for its ability to improve soil structure and increase its water-holding capacity.
- Organic wastes can be broken down and fragmented rapidly by earthworms, resulting in a stable nontoxic material with good structure, which has a potentially high economic value and also act as soil conditioner for plant growth.
- Vermicompost supplies a suitable mineral balance, improves nutrient availability and could act as complex-fertilizer granules.
- Vermicomposting involves great reduction in populations of pathogenic microorganisms, thus not differing from composting from this point of view.
- It should be realized that vermicomposting can be a useful cottage industry for the underprivileged and the economically weak as it can provide them with a supplementary income.
- If every village can formulate a cooperative society of unemployed youth/women group, it could be a wise venture for them to produce vermicompost and sell it back to the village at a recommended price. The youth will not only earn money, but also aid society by providing excellent quality organic manure for sustainable agro-practices.