long before the world started talking about the dangers of climate change and abatement of carbon dioxide (co₂) and methane emissions, Kautilya, an ancient Indian philosopher, almost 1850 years ago, had realised the importance of afforestation and proclaimed (in his book Arthashastra ) measures and methods of preserving forests for the human good. He had thought of productive and non-productive forests separately. His non-productive forests included purposes like 'reserved for ascetics, recreation and as wildlife sanctua-ries and clean air'. Most people would know about the use of forest resources for food and non-food consumption, durable and energy uses, and recreation. But how many of us after Kautilya think of it as a major source of mitigating carbon emissions?

Ever since the Rio conference in 1992, scientists and environmentalists are searching for methods of capping greenhouse gas ( ghg ) emissions on a global scale. Broadly speaking, three different approaches are currently talked about:
• Each country unilaterally opting for reduction of energy productions known as the emission cap approach;
• Countries imposing a carbon tax on firms for exceeding the emission levels known as the fiscal or carbon tax approach;
• Joint implementation in which developing countries transferring part of carbon tax actually collected or collectable, to developing countries for:

• introduction of abatement technologies in highly inefficient hydrocarbon-based energy sectors;

• introduction of renewable energy options;

• creating a carbon sink through forestry in countries with high carbon emissions, with or without transfer of resources from the North.

According to a study by the Tata Energy Research Institute, New Delhi, cost of co 2 reduction through efficiency improvements in energy utilisation in India is about us $45.38 per tonne of carbon on average, whereas it is us $67 under renewable energy technologies and us $27.3 under reforestation options. Similar studies carried out in several countries indicate that carbon sequestration is the most cost effective carbon mitigation technology. Vis-