Garbage dumps contribute methane emissions far more than paddy fields, a new study says, suggesting that these ubiquitous sources of the greenhouse gas must also be taken into consideration while calculating global emissions.
Researchers from University of Calcutta and Centre for Environment Survey, Ahmedabad reported results from a garbage dump in Kolkata where the megapolis' waste was piled till 1991. They measured methane emissions from the low-lying marshy field for two years from May 1995.
Municipalities in rural areas collect garbage from houses and dump it in such fields till it is completely filled up. The ground is then used for public purposes. With the passage of time, garbage starts decomposing and starts releasing methane.
The researchers found that the methane values from the garbage dump were 3–4 times higher than those from the surrounding paddy fields.
Considering that about 20% of total methane emission in the atmosphere comes from the paddy fields, they suggest that garbage dumps should also be considered an important source of methane loading in the atmosphere.
