Saving the Maidan's green cover from pollution and turning it into the Guild's "permanent fair ground' is possible, provided the state government, the pollution control board and the ordinary book lover unite, city-based environmentalists said. The 32nd Kolkata Book Fair could not be held this year, due to the lack of a "permanent fair ground' and a token book fair is being organised at the Salt Lake stadium in March. Environmentalists think the amount of footfall at the book fair and pollution from vehicles are the two factors harmful to the Maidan's environment. "The entire Maidan ground should be covered with a green carpet of grass, whose length should be long or else dust would fly,' said Mr SM Ghosh, a city-based environmentalist. "The ground currently has insufficient grass and many people are even cutting it to feed their animals,' added Mr Ghosh. He said the footfall is also a big problem during the fair. He suggested that if the book fair ground area was doubled, the footfall density would lessen. "The state government should check the pollution level everywhere in the city. Pollution is affecting the Maidan's green, because commercial vehicles, more than 30 years old are plying on the road, emitting poisonous gases. Auto-rickshaws are also running on spurious fuel (Kata Tel, mixture of kerosene, naphtha and petrol),' said Mr Ghosh. Ms Mukuta Mukhopadhya, secretary of Friend of Wetlands and Wild Life as well as an environmentalist, emphasised planting a particular variety of trees to reduce pollution. "Some trees like Banyan, Shiuli and Asatha help in reducing carbon-dioxide pollution. The embankment of a water body that is located in the Maidan and falls within the fair ground ambit should be a natural one,' she said, adding more people should be encouraged to participate in activities involving protection of the Maidan's greenery.