地圖簡化(Map Genera1ization)是編圖過程中最主要的項目，直接影響成圖的品質。傳統的編圖作業，因受制於編圖者主觀意識的影響，對於地理要素在地圖上之表現方式，缺乏客觀性與一致性，難有標準可循。如此使得品質不易控制，間接影響用圖者之設計規劃。爲了確保品質的一致性，電腦化實爲必然趨勢，如何落實地圖簡化工作，則爲自動化製圖發展之重要課題。有關地圖簡化之研究，從文獻中得知國內外地圖學者大都著重於等高線、海岸線、聚落或線條簡化方法等方面之探討，甚少提及水系網的簡化問題。然而水系綱是地圖上之主要地理要素，特別是在反映製圖區的地形上有其重要的意義。基於此，本研究擬以Horton之河流等組分類爲基礎，配合Topfer所提出之選擇原理(Principle of Selection)，探討不同比例尺地圖中水系網簡化之原則。期望經由研究區（木瓜溪與壽豐溪流域）的計測值，利用統計迴歸分析推求水系網之簡化模式，以提供自動化製圖之應用參考。

Map generalization is a very important work in processing the compilation of a map because it directly influences the quality of the map. In convention, the compilation work is done by human; therefore, the quality is determined by the compiler's favor in using a specific map generalization method to express the geographic features. Thus, inconsistency between maps can frequently be found due to the lack of a unifed standard for map compilations, causing great inconvenience to the users. In order to control the quality, the computer-aided map compilation is necessary, however, practical generalization rules for different geographic elements shown on a map have to be establish first. Development of these rules thus becomes an important issue to modern cartography. According to our survey, map generalization of contours, settlements and drawing has been studied by many scholars. However, generalization of river networks on a map is seldom studied. Since the river network is a also an important geogrhic element of maps, a study on this subject is then of the great interest. The present study is conducted on the basis of Horton's stream ordering and Topfer's principle of the selection. To derive a generalization rule for river network s shown on maps of different scales, the basin of Mukua Hsi and Shoufeng Hsi in Taiwan have been chosen to be samples to be analyzed. According to the analysis, the generalization model of river networks is then developed, using a statistic regression menthod and is expected to be a practical reference for the devlopment of automatic cartography.