title: Sub-regional dimensions of agricultural and environmental nitrogen: the case of Asia.
abstract: Asia embraces a wide range of cropping environments, largely related to the diversity of climate. To meet the high food requirements of a very large population (some 59% of the earth's total) large inputs of mineral N fertilizer are required (44.2 Tg N x yr(-1) in the mid 1990 s). However, because of the low (20%-50%) overall efficiency of use of fertilizer N, sometimes coupled with heavy use in intensively-farmed areas (for example in parts of China), losses of fertilizer N from agricultural land are expected to be high. Part of the N lost is thought to cause pollution of the atmosphere and water resources. A sub-regional approach, based on the FAO Agroecological Zone (AEZ) concept, has the potential to provide meaningful assessments of the agricultural and environmental dimensions of N. The AEZ concept can also provide the rationale for locating Sub-regional Centers of the International Nitrogen Initiative (INI) by basing the considerations, as far as practicable, on agroecological conditions.
authors.affiliation: School of Science, Mae Fah Luang University, 57100, Chiang Rai, Thailand. keith@mfu.ac.th
authors.forename: John Keith
authors.initials: JK
authors.lastname: Syers
mesh_terms: D000383:Agriculture / Q000379:methods*; D001208:Asia; D002681:China; D002980:Climate; D018556:Crops, Agricultural; D004463:Ecology / Q000379:methods; D017753:Ecosystem; D004777:Environment; D004787:Environmental Pollution; D005308:Fertilizers; D009584:Nitrogen / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014873:Water Pollutants
chemical_list: D005308:Fertilizers; D014873:Water Pollutants; D014867:Water; D009584:Nitrogen