1 农业信息建设的必要性我国地域辽阔,农业资源与环境从南到北,自西向东,类型很多,差别很大。土地及耕地面积、水资源,以及农业环境的污染情况等随时间的变化很快,因此需要依靠农业信息化加以及时而准确地掌握。农作物品种与栽培每年都有变化,特别是气象、水文与病虫情况,每时每刻都在变化。因此,建立以计算机联网为基础的农业信息网络,是我们农业工作 1 The necessity of agricultural information construction China’s vast territory, agricultural resources and environment from south to north, from west to east, many types, very different. Land, cultivated land area, water resources and pollution of agricultural environment change rapidly over time. Therefore, it is necessary to rely on agricultural informatization to grasp timely and accurately. Varieties and cultivation of crops vary from year to year, especially in meteorology, hydrology and pests and diseases, changing every moment. Therefore, the establishment of an agricultural information network based on computer networking is our agricultural work