Mains Paper: 3| Environment: Pollution, Agriculture
Prelims: Incineration, composting, NGT
Mains level: The article can be tagged to GS 3 paper topic Environmental pollution. The article provides important fodder which could be utilized by an candidate while writing an answer to question related to Solid waste management
This article talks about how city compost can help in making cities cleaner, increasing agricultural productivity and also replenishing nutrient depleted soil.
Problems in Current solid waste management strategy
- Waste management to keep cities clean is also being given attention in Swach Bharat Abhiyan . But the attention begins and stops with the brooms and the dustbins. The collected mixed waste is transported not to distant places but just taken out of sight.
- The challenge of processing and treating the different streams of solid waste, and safe disposal of the residuals in scientific landfills, has received much less attention in municipal solid waste management.
- But, one of the major problem that comes in our endeavor to create clean cities is we focus on waste for energy rather our focus should be waste management for health.
- In process we opt for financially and environmentally expensive solutions such as incineration plants which are highly capital-intensive.
- While the National Green Tribunal (NGT) does not allow incineration of mixed waste, nor of any compostables or recyclables, enforcement is a challenge, and the danger to health from toxic emissions looms large.
- The biodegradable component of solid waste (close to 60 per cent of the total) should not be mixed with the dry waste rather it should be used for composting and biomethanation.
- The management of dry waste can be done through recycling and processing and incineration of non-recyclables can be done with appropriate filters to check emissions. The need for scientific landfills will be very less then.
Advantages of Compost
- It is an alternative to farmyard manure (like cowdung) which has been valued for its rich microbial content that helps plants to take up soil nutrients.
- It provides an opportunity to simultaneously clean up our cities and help improve agricultural productivity and quality of the soil.
- The water holding capacity of the soil increases and it also helps with drought-proofing.
- By making soil porous, use of compost also makes roots stronger and resistant to pests and decay.
- There is also evidence to suggest that horticulture crops grown with compost have better flavour, size, colour and shelf-life.
- Chemical fertilisers when used by themselves pollute surface water with nitrogen runoff because only 20 per cent to 50 per cent of the nitrogen in urea is absorbed by plants. The rest runs off into streams and lakes. The addition of compost or organic manure reduces nitrogen wastage, as its humus absorbs the nitrogen and acts like a slow release sponge.
Advantages of City Compost
- It is weed free.
- It is rich in organic carbon. Fortification of soil with organic carbon is an essential element of integrated plant nutrient management as it increases the productivity of other fertilisers.
- City compost can also be blended with rock phosphate to produce phosphate-rich organic manure.
- Farmers recognize the advantages of compost and they dump reasonably biodegradable raw garbage onto their fields for making compost onsite for their own farm use.
- But, uncovered and uncomposted raw waste helps breed rats and insects which carry disease, and attract stray dogs which not only carry rabies but form hunting packs that kill nearby livestock at night. Also causing dog bites and traffic accidents.
- If city waste was composted before making it available to the farmers for applying to the soil, cities would be cleaned up and the fields around them would be much more productive.
- It requires that delivery mechanisms be set up for the delivery of city compost to farmers.
- The Supreme Court had directed fertiliser companies in 2006 to co-market compost with chemical fertilizers but it was largely unheeded.
- The Solid Waste Management Rules 2016 make the co-marketing of compost mandatory.
- The payment of fertiliser subsidy to the fertiliser companies can be made conditional on the co-marketing of compost.
- The state agricultural departments can also help facilitate the use of city compost through their widespread extension networks.
- Assuming that urban India generates 70 million tonnes of municipal solid waste in a year, and assuming 15 per cent yield of compost, this would provide 10 million tonnes of city compost annually.
- It can be a major and sustainable contribution to improving the health of our soil.