Syers John Keith
School of Science, Mae Fah Luang University, 57100, Chiang Rai, Thailand.
Sci China C Life Sci. 2005 Sep;48 Suppl 2:738-44. doi: 10.1007/BF03187114.
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.
亚洲拥有多种多样的种植环境，这在很大程度上与气候多样性有关。为满足庞大人口（约占地球总人口的59%）对粮食的高需求，需要大量投入矿物氮肥（20世纪90年代中期为44.2太克氮/年）。然而，由于氮肥的总体利用率较低（20%-50%），有时还加上集约化种植地区（如中国部分地区）的大量使用，预计农田中氮肥的损失量会很高。损失的部分氮被认为会造成大气和水资源污染。基于粮农组织农业生态区（AEZ）概念的次区域方法，有可能对氮的农业和环境层面进行有意义的评估。AEZ概念还可为国际氮倡议（INI）次区域中心的选址提供依据，即在可行的情况下，根据农业生态条件进行考量。
