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一、建立数据库的意义 北京市水土流失综合调查获得了百万个以上的数据,而将这些数据进行整理使之为水土保持生产科研服务,改善我们当前水土保持的管理水平,满足四化需要。因此从实际要之求出发,我们探讨使用了电子计算机技术,即建立了“水土流失综合调查数据库”。数据库由五种基本统计表的数据系统和十四种应用信息系统统计表组成。它包括了实体、关系、属性三种成分。实体指自然界客观存在的地质、土壤、坡度、植被等因子;关系指客观存在的因子和水土流失及其治理
First, the significance of establishing a database Beijing integrated soil and water loss survey obtained more than 1 million data, and these data will be organized into soil and water conservation production and research services to improve our current soil and water conservation management level to meet the four needs. Therefore, starting from the actual requirements, we explored the use of electronic computer technology, which established the “Soil and Water Loss Comprehensive Survey Database.” The database consists of five basic statistical data systems and 14 application information system statistical tables. It includes the entity, the relationship, the three attributes of the property. Entity refers to the objective existence of the natural world of geology, soil, slope, vegetation and other factors; relationship refers to the objective existence of factors and soil erosion and its governance