composting and vermicomposting, a simple … 14/rinku... · · 2011-01-06composting and...

Lake 2010: Wetlands, Biodiversity and Climate Change

22nd-24th December 2010

COMPOSTING AND VERMICOMPOSTING, A SIMPLE WAY !

Dr. Rinku Verma

Faculty in Environmental Science Department, Bangalore University

[email protected]

Abstract

In any environment, recycling of the degradable waste is the natural way of replenishing it. Because of the

negligence and indifference, the damage to the environment has surpassed the replenishment. The

concentration of the toxic matter has increased which in turn has decreased the pace of the natural

degradation. Poisonous gases in the atmosphere, concentration of the chemicals in the soil and water etc

have accelerated the development of pathogenic mutants of organisms which by infecting human beings,

animals and crop contributed to the decline in the productivity. This is the major stumbling block in the

advancement of the nation. The methods to curb the environmental degradation and also improve the

environment are area specific, as the parameters are different at different areas. This paper highlights

simple methods used for composting and vemicomposting of organic waste. The usefulness of

vermicompost has also been indicated.

Introduction

Waste is a useful material in a wrong place. It is a reusable resource and national asset. It is a rich

source of food and energy if utilized properly. If not it is polluting, creates health and aesthetic problems.

We want India to be in the developed nation in the next few years. Importance hence must be given to

waste management and energy from the waste and manure making which is one of the steps towards

sustainable development.

Source –wise Generation of Solid Waste in Bangalore Stake holder Volume (tonnes/day) % Households 650 18 Commercial Establishments Markets Hotels

369 1066

39

Institutes 128 Hospitals Offices Educational institutes

20 15 92

Industries 1399 39 Total 3613 100 (Pieter et al, 1999)



It becomes necessary to do composting at home, in the neighbourhood, parks, schools etc., as

already some areas are doing. Absence of a proper landfill site can be considered as the most important

short term issue in solid waste management in Bangalore. Fraction of compostable materials is collected by

the municipality and delivered to farmers near Bangalore city who use it to enrich their soil.

Efforts are being carried out in Bangalore by bringing NGOs, Schools, and Colleges to take part and have a

better waste management program.

According to earlier estimates, during the mid 90’s Bangalore generated approximately 2,000 tonnes of

solid waste per day, which was in the later years estimated to be around 2,500 tonnes per day. At present, it

is estimated that Bangalore generates about 3,613 tonnes of solid waste per day including industrial waste

as given in the above table.

The municipality collects about 1,139 tonnes of waste per day from the Public Dust Bins. Of this, about

200 tonnes are directly sent from the major markets to large composting units such as Karnataka

Composting Development Corporation (Govt concern) and several private composting units located in the

city. The remaining waste collected by the municipality is dumped in open spaces and on road sides outside

the city. In addition, about 245 tonnes of waste per day is dumped or burned by the generators themselves.

This may include debris burnt waste etc., (unorganized waste) which remain uncollected in the city.

From Bangalore we have the following percentage of waste 30-35% Biodegrade 20-35% Fine/street waste 20-35% Waste with moisture content 10-12 % Recyclable Including a lot of E – Waste, because Bangalore is an IT hub with many IT companies. It is estimated that by 2020 we would have 13 million tonnes of solid waste. And by 2030 this would go up

to 2000 million metric tones. It may go up to 48 million tonnes by 2047.

Managing solid waste, the composting way!! “Solid waste management at home” -The Domestic Way Biodegradable solid waste is the cause of a number of diseases due to water and air contamination.

If the biodegradable waste is converted into compost it not only reduces the pollution but also is profitable.

There is some awareness about the conversion of the waste into compost. But majority of the public is still

unaware of this. Otherwise, the cities like Bangalore, Mumbai etc., would not be stinking with the garbage

littered on the side walks, garbage bins and the municipalities with collection problems of disposing off the

waste. The problem is increasing in leaps and bounds.

Hence initiation of popularizing the solid waste management, organic farming, reclamation of the

degraded land and purification of the polluted water and air would be very useful in sustainable

developmental practices, with “Ecological research interest for alleviation of the environmental problems”.



Fresh compost being collected after biodegradation

Pit filled with compost and the fresh waste above Solid waste at home is to a large extent biodegradable and a small quantity of it may be degradable or non

degradable. Biodegradable waste is a nuisance as it decays rapidly and produces obnoxious smell if not

disposed in the right way.

Biodegradation in the right way is very beneficial. Biodegradable waste is of plant and animal origin. It

may be kitchen or garden waste. This can be easily converted into compost and profitably used in growing

plants in your garden or in the pots.

Compost improves the quality of the soil and supplies nutrients to the plants

To prepare the compost (with reference to kitchen waste, garden waste can be used if the area is

larger)

1. Make at least two pits in the garden or get two drums of convenient size,

2. Throw the biodegradable waste into one of the pits or the drums,

3. Cover the waste by a layer of soil to prevent any smell from the waste escaping,

4. Sprinkle water to keep the soil and the waste wet,

5. Whenever waste is available throw it into the pit or the drum and cover by the mud, (option, if

composting is done in pits cover by mud layer can be once a week and just a thin layer)

6. Sprinkle water,

7. Repeat the process till the pit or the drum is full,

8. When the pit or the drum is full, sprinkle water at intervals of two or three days,

9. Repeat sprinkling of water for a month or more,

10. In the mean time use the other pit or the drum and repeat the procedure.



11. Provide any option for a small hole at the bottom of drum. So that excess water can be removed.

12. Provide a covering if possible over the drum or pit.

In about a month/two after the pit or the drum is full it will have a healthy blackish powder of compost

without any offensive smell. Non-pathogenic microorganisms have done their job.

Take out the compost.

Sieve it to remove the undegraded material which may be few sticks or the other non degradable material

which have fallen into the pit by mistake.

Burn the undegraded organic matter (sticks etc) and mix the ash with the compost

This compost can be used during planting, by mixing it with the soil. The proportion of mixing the compost

with the soil depends on the type of the plant. The plants grown in the compost soil mixture are lush green

and are more productive. Flowers and fruits produced are better in taste and flavour. Consumable produce

is good for health.

Time taken for monitoring composting may be few minutes every day. But the returns are

significant. Apart from the returns, it is a service to the society. If every body takes up this, there will be no

stink and filth around. So as a good citizen it is our duty to do this and propagate the idea.

Procedure followed:

1. Spread the waste in the pot or the drum.

2. Watering should be only to wet the soil and the waste. If more water is poured there will be

water logging and quality of the compost will be spoilt.

3. Let the waste undergo complete degradation otherwise a stinking odour prevails (this is the

time when waste is sill in the process of biodegradation rather getting decomposed to form a

compost, this should not be applied to the plants as it is still not ready).

4. Family members, including children can get together to make a compost, it is so easy.

Normal Compost Making Method : The Commercial/ Institutional Way

1. Collection

2. Separating plastic, metallic items, thermocol,

3. Digging of the pits 6*4*4, can be longer. The pits can be lined by cement bricks. But the

bottom should be of clay bricks

4. Load the pits with vegetable matter cut into small pieces. Soft and tender parts are only loaded

into the pits. Woody parts can be burnt and the ash can be used. Load the vegetable matter to

a height of 2 ft.

5. Put a layer of dung

6. Cover the pits by mud which is sieved to remove stones to a depth of 2 to 3 inches

7. Water to drench the mud and wet the materials below



8. The process is repeated by another layer so that the mound is a foot so above the ground level.

It is better to prepare all the layers at a time in few days the mound will subside to below the

ground level.

9. Watering should be done every alternate day, moderately so that there will not be any water

logging. There is no need of watering during the wet seasons. If available urine can be poured

into the pit. The soil layer at the top of the pit better be 4 inches thick. Cover the filled pits by

palm frounds.

10. Compost will be ready in a month or two. Addition of bone meal, meat meal, poultry

dropping et., improve the quality of the compost

Vermicomposting :

During the process of vermicomposting earthworms maintain aerobic conditions in the organic wastes by

proper mixing and microbial decomposition of the substrate in the intestine of earthworm, converting the

organic wastes into worm biomass and excretion of casts which are vermicompost (Benitez et al., 1999).

Preparation of Vermicompost expressed diagrammatically

Sprinkle water, Add every day 6cm thick organic waste, Water, Compost will be ready in 30-60 days (depends on the number of worms, climate etc.,), Remove, Sieve, Use worms again, (Clean up after every operation)



Wire netting

Organic material

Earthworm

Fresh Farm Yard Manure

Coir (10cms)

Pebbles (10cms)

Stills

Worm wash

Points to be noted Neem powder is required to be added to the compost to avoid fly Cowdung is applied on the surface of the compost Aeration and Mixing is required (3 times), start only after 10th day Provide a mesh (net) above the surface at an elevated height Add culture of microbes into the mixture of compost & interfering chemicals This process is known as “bioaugmentation” to improve either efficiency or rate of abatement of organic pollution Possible degradation of a wider number of organic pollutants should be taken into account while composting carried out in mesophilic range Coconut husk acts as a mesh to cover the pits. This is to avoid files and other insect rodents.



Types of vermicompost bins necessary for a better yield and multiplication of earthworms

Picture 1. Indicates bins/box made specifically for Vermicomposting (100 worms have to be put inside one such bin/box)

40 days vermicompost is ready

100 worms multiply to 400 worms

Cost of earthworms are Rs 450/- for 1000 earthworms

Layers of waste have to be put

The bins have pores below them and water easily drains away, without stagnation into the bins making it

suitable for earthworm activity

Using a shower can regularly keep this unit moist; preferably when the bin is filled a wet jute material is

put above and covered.

During vermicomposting one has to remember to separate the worms before the manure is added to the

plants and use earthworms which produce compost at a faster rate.

The disadvantage of this bin is the side plastic sheet has to be changed once or twice in a year and hence it

is recommended to just have this as a sample.



Picture 2. Pits made above the surface of the ground (cement construction of pits, a view) The commercial way! The above pictures, 2 can be used for vermicomposting or composting purposes. Care should be taken to

avoid the ants as they may damage the worms.

Some Don'ts...

Don't put plastic bags, bottle caps, rubber bands, sponges, aluminum foil and glass in the bin. These

materials will be there forever and make your worm bin look like trash.

Don't let your cat use your worm bin as a litter box. First, cat urine would soon make the odor intolerable.

Secondly, the ammonia in the urine could kill your worms. There is also a concern with toxoplasmosis, a

disease that is of particular concern to a pregnant woman who may pass on the disease to her unborn child.

If you have cats, provide a screen or other device to keep them from using the worm bin as a litter box.

Don't use insecticides around your worm bin. You'll not only take care of a few pests, but also your

worms.

Don't use garden soil as bedding for the worms.

Don't mix fresh cow, horse and especially chicken manure into your bedding. These manures will heat up

the bedding and literally cook your worms (Mary Appelhof

http://lancaster.unl.edu/pest/resources/107Vermi.pdf).

Information related to earthworms and vermicast

Choice of the right species of earthworm for vermicomposting is foremost step of vermicomposting ( Aliva

Patnaik, http://dev4india.org/articles/vermitechnology.html). Earthworms (also called nightcrawlers) are



very important animals that aerate the soil with their burrowing action and enrich the soil with their waste

products (called castings). Good soil can have as many as as 1,000,000 (a million) worms per acre.

Earthworms play an important role in soil ecology. By being continually loosened, stirred up, and aerated

by the action of earthworms, soil is made more fertile. Earthworms also form a source of food for many

animals, and constitute the principal food of moles and shrews.

Earthworms must live in moist soil containing organic matter. During unusually hot weather they also

penetrate downward to avoid dehydration. Earthworms shun daylight, but frequently come to the surface of

the soil at night to feed and to throw off their castings. In the daytime they appear upon the surface of the

soil only under unusual conditions, such as the flooding of their burrows by excessive rainfall.

In burrowing, they swallow large quantities of earth that often contain considerable amounts of vegetable

remains. They are able to digest the nutritive matter of the soil, depositing or casting out the remains on the

surface of the earth or in their burrows.

Diet: Earthworms eat soil and the organic material in it - like insect parts and bacteria.

Earthworms, as they burrow and feed, swallow the soil, digest it, extract its food value and expel the

residue as worm castings which are far richer in nitrogen, phosphate, calcium, and magnesium than the

finest of ordinary good top soil. Worms actually MAKE rich dirt. Not only do worms create this wonderful

soil for our gardens and yards, but composting also greatly reduces the amount of the garbage that is sent to

our dumps and landfills.

Worms love to eat all kinds of food. They love food scraps, (but not meat, bones, or dairy products

because these may cause unpleasant odors or invite unwanted ‘guests’ into your worm bin). They also eat

cardboard, and even material from vacuum cleaner bags. Then they turn it into nutrient-rich compost



(castings). These castings can be used as a fertilizer for all types of plants. Worm castings are the richest

form of natural fertilizer known to man. This will promote higher than average growth in plants

Earthworm Life Cycle:

Earthworms are

amazingly prolific breeders. A thousand mature breeders, properly cared for and allowed to multiply, may

give you half a million or more breeders, growing earthworms, and egg capsules within a year. Earthworms

are bisexual, having both male and female reproductive organs. Each worm produces egg capsules, but

must first be fertilized by contact with another worm. Each healthy worm, under favorable conditions, will

produce an egg capsule every 7 to 10 days. These incubate in 14 to 21 days, each hatching 2 to 20 young

worms, with an estimated average of 4. The new worms thus hatched will reach breeding age in 60 to 90

days, as indicated by the formation of clitellum...a thick ring about 1/3 the length of the worm from its

head. The domesticated earthworm will continue to grow, after reaching the breeding stage, for perhaps six

months or more before reaching its full size (http://www.workingworms.com/index.html).

Earthworms for Soil Improvement:

The earthworm has been aptly called, "The Gardener's Unpaid Handyman." It tills the soil around root

areas by its tireless burrowing. The burrows form channels through which root growth may reach down into

the subsoil for minerals and moisture. They also absorb rainfall quickly for storage in the soil instead of

allowing it to run off, carrying away valuable top soil. Most important of all, the earthworm eats, digests,

and enriches dead and decaying vegetable wastes in the soil, ejecting it in the form of casts (as mentioned

earlier), rich in plant food value, water soluble, immediately available to plant roots.

For the success of your vermicomposting:



It is important to note that do not feed earthworms; metals, foils, plastics, chemicals, oils, solvents,

insecticides, soaps, paint, etc. Avoid all citrus products (oranges, lemons, limes, grapefruit), onions, garlic

cloves, extremely hot and heavily spiced foods, and high acid foods. Also, avoid oleanders and other

poisonous plants meat, chicken, dairy foods, dog and cat manure (NIIR Board,2004).

Earthworms can be fed all forms of food waste, yard and garden waste, paper and cardboard, etc. Yard

wastes, such as leaves, grass clipping, straw, and non woody plant trimmings can be composted. Leaves,

are the dominant organic waste in most backyard compost plies. If grass clippings are used, it is advisable

to mix them with other yard wastes, otherwise the clippings may compact and restrict airflow. Branches

and twigs greater than ¼ inch in diameter should be put through a shredder/chipper. Kitchen wastes such as

vegetable scraps, coffee grounds, and eggshells may also be added. Sawdust may be added in moderate

amounts if additional nitrogen is applied. Approximately 1 kg of actual nitrogen is required for 100 kg of

dry sawdust. Wood ashes act as a lime source and if used should only be added in small amounts (5 kg per

ton of waste). Ordinary black and white newspaper can be composted; however, the nitrogen content is low

and will consequently slow down the rate of decomposition. If paper is composted, it should not be more

than 10% of the total weight of the material in the compost pile (NIIR Board 2004).

Animal dung

Cattle dung, sheep dung, horse dung, goat dung and poultry dropping etc may used for this purpose. In use

of animal dung other than cattle dung, various preliminary testing and precautions for pathogens and

responses to earthworms are necessary. The uses of horse dung should be done carefully because tetanus

virus is common in horse dung and is lethal to human beings.

Agricultural waste

Agricultural waste obtained after harvesting and threshing may be used. They include stem, leaves, husk

(excepting paddy husk), peels, vegetable waste, orchard leaf litter, processed food wastes, sugarcane rash

and baggase; and processing wastes.

Forestry wastes

These are plant products such as wood shavings, peels, saw dust and pulp. All these besides various types

of forest litter can be used. The unutilized forest waste such as leaf litter may also be used for

Vermicomposting.



City leaf litter

The burnt leaf litter from avenue or residential areas may be used, however, reports are not available. If it is

used, this would keep cities clean and would provide useful product. The leaf litter of mango, guava,

grasses and certain weeds (free from seeds) may be used, but we need more information on this aspect.

Waste paper and cotton cloth etc.

These are decomposable organic waste. These if are not being recycled for other useful products, can be

recycled with Vermicomposting.

City refuse

City refuse or garbage on daily production basis comprise important items of city factors and a

considerable portion of city refuse can be sorted and recycled or composted. Most of household as kitchen

waste with little manipulation can be used for vermicompose.

Biogas slurry

After recovery of biogas, if not required for agricultural use, viz., in conventional composting can be used

for Vermicompositing.

Industrial wastes

The industrial wastes like waste from food processing, distillery etc. can also be used in vermiculture with

some manipulations.

Vermicast

Vermicast is produced by the feeding action of earthworms. Earthworms ingest organic matter, fragmenting

and grinding it into a finely divided peat like material with high porosity, aeration, drainage and water

holding capacity. This process enhances microbial activity and accelerates the rate of decomposition. This

leads to a humification effect where unstable organic matter or decomposing plant and animal matter is

oxidized and stabilized. Micro organisms present in vermicompost inactivate and suppress the growth of

pathogens (Kale, 1998; Shobha, 2005).

Humus forms the dark brown or black mass of the upper soil and is important for storing and releasing

plant nutrients. The process is similar to composting except it is non thermophilic or a cold process utilising

naturally occurring soil dwelling microorganisms. Vermicast has a large surface area and a high cation



exchange capacity providing strong absorbability and retention of nutrients (Atiyeh et al, 2001).

As a fertiliser, vermicast contains nutrients in a form that are readily taken up by plants, such as nitrates,

exchangeable phosphorous, soluble potassium, calcium and magnesium (Edwards & Burrows, 1998)

A typical breakdown of vermicast is as follows:

pH N P K S Mg Ca CEC (Me/100g) Organic Matter (humus)

6.6 2.3 3.0 0.6 0.1 0.65 8.6 52.75 20%

Comparison between Vermicast V/s. Chemical Fertilizers

Criteria for Comparison

Chemical Fertilizers Vermicast

Macro nutrient contents

Mostly contains only one (N in urea) or at the most two (N & P in DAP) nutrients in any one type of chemical fertilizer

Contains all i.e. nitrogen (N), phosphorus (P) & potassium (K) in sufficient quantities

Secondary nutrient contents

Not available Calcium (Ca), magnesium (Mg) & sulphur (S) is available in required quantities

Micro nutrient contents

Not available Zinc (Zn), boron (B), manganese ( Min), iron (Fe), copper (Cu), molybdenum (Mo) and chlorine (CI) also present

pH balancing Disturb soil pH to create salinity and alkalinity conditions

Helps in the control of soil pH and checks the salinity and alkalinity in soil

EC correction Creates imbalance in soil EC Affecting nutrients assimilation

Helps in balancing the EC to improve plant nutrient adsorption

Organic carbon Not available Very high organic carbon and humus contents improves soil characteristics

Moisture retention capacity

Reduces moisture retention Capacity of the soil

Increases moistures retention capacity of the soil

Soil Texture Damages soil texture to reduce aeration

Improves soil texture for better aeration

Beneficial bacteria fungi

Reduces biological activities and Thus the fertility is impaired

Very high biological life improves the soil fertility and productivity on sustainable basis



Plant growth hormones

Not available Sufficient quantity helps in better growth and production

http://www.morarkango.com/biotechnology/research.php

References: Aliva Patnaik http://dev4india.org/articles/vermitechnology.html Atiyeh, R.M., Arancon, N., Edwards, C.A., Metzger, J.D., 2001. The influence of earthworm processed pig manure on the growth and productivity of marigolds. Bioresource and Technology 81, 103-108., Benitez, E., Nogales, R., Elviva, C., Masciandara, G. and Ceccanti, B. 1999. Enzymatic activities as indicators of the stabilization of sewage sludges composting with Eisenia foetida, Bioresource Technology 67: 297-303. Edwards, C.A., 1998. The use of earthworms in the breakdown and management of organic wastes. In: Edwards, C.A. (Ed.), Earth-worm Ecology. CRC Press, Boca Raton, FL, pp. 327±354 Kale, R.D. 1988. Earthworm; Cinderella of organic farming. Publ. Prism Books Pvt. India pp. 88. Mary Appelhof, Worms eat my garbage, Published by Flower Press10332, Shaver Road, Kalamazoo Michigan 49002 http://lancaster.unl.edu/pest/resources/107Vermi.pdf

Morarka Foundation http://www.morarkango.com/biotechnology/research.php

National Institute of Industrial Research Board 2004, The complete technology book on Vermiculture and Vermicompost. Published by NIIR, pages 354 http://niir.org/books/book/complete-technology-book-on-vermiculture-vermicompost-niir-board/isbn-8186623817/zb,,74,a,5,0,3e8/index.html

Pieter von Beukering, Madhushree Sehker, Reyer Gerlagh and Vijay Kumar, 1999. Analysing Urban Solid Waste in Developing Countries: a Perspective on Bangalore, India, Working Paper No 24, Institute for Social and Economic Change Bangalore 72

Shobha, S.V. 2005. Influence of earthworm extracts on some plant pathogens. M.Phil. Dissertation submitted to Bharathidasan University, TN, India pp.51.

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