Namaste Panditji...

What is an eco-friendly vehicle?

Tadasmi Koul, Noida, U.P

An Eco-friendly vehicle is one which leaves behind no harmful residues in the form of gases from fuels like petrol or diesel, or toxins from battery packs/fuel cells. Unfortunately, such a vehicle does not exist.

The main criteria today is emission which is determined by the fuel, the engine (the direct injection engine is superior to the conventional carburettor engine) and the use of catalytic converters. The fuel quality is most important. Direct injection engines and catalytic converters function best to minimise emissions only with high quality fuel. Toyota, for now, may have the best solution.

It has designed a hybrid car called Prius. The car runs on a combination of electric power and a petrol engine to deleiver an effieciency of 28 km/litre.

MY sister has kept 400-500 earthworms. She says earthworms eat up debris, where they have been kept and their castings can be used as fertilisers. Do earthworms really eat debris and convert it to something useful? Aren’t they just borers ?

Namrata Thapa, Lalitpur, Nepal

Your sister has done a wonderful thing by keeping these wonderful wriggly earthworms. Earthworms are borers. But this aerates the soil helping it to absorb water and air. Earthworms recycle waste equivalent to their body weight each day. They eat up all the organic matter — but are strict vegetarians — and convert it into top grade fertiliser with the qualities of humus and correct NPK (nitrogen, phosphorus and potassium) balance which are essential for a fertile soil.

What your sister is doing is called vermicomposting. Vermicomposting involves keeping earthworms in a pit containing organic waste like kitchen and garden waste. Earthworms eat up all this organic waste and the excreta they produce is used as an organic fertiliser.

There are hundreds of thousands of cows and buffaloes roaming the Indian roads causing nuisance to the traffic. How can this stray cattle be utilised?

Soumya Mukerji, Gorakhpur

Catile on the streets have been let astray by their owners after they have stopped producing milk and hence nobody is willing to take care of them. Some voluntary agencies like the Sanjay Gandhi shelter for animals in Delhi tends these cattle. Some of the cattle, however, do produce milk. Due to shortage of grazing grounds in cities, cattleowners leave them to graze during the day and milk them in the evening when they return home.