【摘要】 地块单元是小流域生态环境建设与管理的基本空间单元 ,探讨地块尺度的水沙运移关系对强化小流域空间管理具有显著的理论与实践意义。本文在论述地块单元的特点、作用和功能的基础上 ,阐述了在地理信息系统支持下 ,地块单元的划分、参数组织、地块属性的确定及信息提取方法 ,并针对小流域水土保持规划管理、水土流失计算、生产潜力评估、经济与生态效益分析 ,开发了小流域地块汇流网络模型 ,进而对典型小流域地块汇流关系进行了模拟计算更多还原

【Abstract】 Land unit is the basic unit in soil erosion management and ecological environment construction. To understand the roles of water and sand movement among the land units is significant in spatial management of small basins. The land unit is defined as a piece of land with homogeneous geographic characteristics. Within a land unit, the elevation, slope, aspect, soil type or soil texture, landuse or landcover are same or similar. It is now becoming much important in land planning and land management. This paper described the characters and functions of land unit. Based on geographic information system, the methods for land unit dividing, parameters organization, and attribute extraction were expatiated. To meet with the needs of soil erosion model, land productive model and socio economic model, which are main models developed for soil and water conservation measures, a mathematical model for calculating flow network among land units in small catchment was developed. The data set used in the model was grid format elevation data and land unit data layer. The model result was a relation table which shows flow structure of water and sand movement among land units. The flow network relation table then was connected with the erosion model to give out the flow sequence of erosion process.更多还原