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在发展中国家，如何确定流域分级，合理支配治理资金，解决流域治理实际问题，至关重要。而流域等级的划分，通常需要大量的外业调查、内业计算的时间及技术投入、资金投入。但多因受资料来源、信息应用的限制，影响分级各类的精度。地理信息系统ＧＩＳ可以精确地分析流域等级的各种参数，进行准确地分级，可减少大量的内业时间和资金的投入。流域的类别分级划分可分为流域类别规划的发展，实地勘测、调查及对数据资料的评估，流域优先配给三步骤。分级标准主要包括环境标准、区域优势、社经条件、农业优势等４个条件８项条款。收集资料包括自然资料、土地利用资料及社经资料，利用ＧＩＳ进行评估、设计流域分级程序，收集立体图象，对现存地图进行数字化处理，判定流域整体的稳定性，最后得出指导性结论。
In developing countries, it is of crucial importance to determine the watershed grading, rationally govern the funds and solve the practical problems of watershed management. The division of river basin level usually requires a lot of field investigation, calculation of the time and technology investment, capital investment. However, due to the limitations of information sources and application of information, the accuracy of grading and classification is affected. Geographic Information System GIS can accurately analyze the various parameters of the basin level, accurately grading, can reduce a lot of time and money invested in the industry. The classification of watersheds can be divided into the development of watershed category planning, field surveys, surveys and assessment of data and the river basin priority allocation for three steps. Grading standards include environmental standards, regional advantages, social conditions, agricultural advantages of the four conditions of eight terms. Collecting data includes natural data, land use data and social economic data, using GIS to evaluate, designing watershed grading program, collecting stereoscopic images, digitizing the existing maps and judging the overall stability of the watershed, and finally draw the guiding conclusions.