During the 20th century, paddy-field farming became the dominant form of growing rice.àHill tribes of Thailandàstill cultivate dry-soil varieties calledàupland rice. àPaddy field farming is practiced inàAsia, namely inàCambodia,àBangladesh,àChina,àTaiwan,àIndia,àIndonesia,àIran,àJapan,àNorth Korea,àSouth Korea,àMalaysia,àMyanmar,àNepal,àPakistan,àthe Philippines,àSri Lanka,àThailand,àVietnam, andàLaos, and inàEurope,àNorthern Italy, theàCamargueàinàFrance, and inàSpain, particularly in theàAlbufera de Valènciawetlands in theàValencian Land, theàEbre DeltaàinàCataloniaàand theàGuadalquiviràwetlands inàAndalusia, as well as along the eastern coast ofàBrazil, theàArtibonite ValleyàinàHaiti, andàSacramento ValleyàinàCalifornia, among other places. Paddy fields are a major source of atmospheric methane and have been estimated to contribute in the range of 50 to 100 million tonnes of the gas per annum. Studies have shown that this can be significantly reduced while also boosting crop yield by draining the paddies to allow the soil to aerate to interrupt methane production. Studies have also shown the variability in assessment of methane emission using local, regional and global factors and calling for better inventorisation based on micro level data.
|
