New Delhi, Feb 8 (IANS): Replying to a supplementary question on the situation of air quality in Delhi, Union Minister of Environment Prakash Javadekar said that the main reason behind deteriorating air quality in the national capital in the month of Septmeber to November is the stubble burning in Haryana and Punjab.

He said that stubble burning in Punjab has increased by 75 per cent this year while it has increased by 25 per cent in Haryana.

Union government has spent huge amount on providing 40,000 machines to the states but they are used seldom. The wind during September to November is eastward due to which the pollution increased in Delhi, the minister added.

The government said that the problem of Delhi is that it has alluvial soil which results in the dust while the city's like Bangaluru have rocky soil.

The AQI on Monday in Loni, Ghaziabad and Delhi was reported to be 456 and 393 respectively, which falls under hazardous category.

The government said that we will introduce the Pusa model of decomposition process of stubble and promote it.