CAJ | 학술논문

水系不但是重要的自然地理要素，而且对防洪减灾、资源开发等有着重要意义。基于DEM的坡面径流法是最为常用的水系提取方法，其提取精度直接取决于DEM中洼地的处理方法。为了比较不同DEM处理方法对水系提取精度的影响，本文以江西省潦河流域为例，利用基于DEM数据的J＆D算法及基于辅助数据的AGREE方法来处理实验区DEM，然后利用坡面径流法提取水系。结果表明，经两种方法后均可以提取出连续的水系，且提取水系的等级、数量及长度相差不大；在提取精度上，在受人类活动影响较小的山地丘陵地区两种方法提取的水系比较吻合，而在平坦地区或受人类活动影响较大的地区提取的水系差异较大，且AGREE方法处理后提取的水系精度较高。
수계불단시중요적자연지리요소，이차대방홍감재、자원개발등유착중요의의。기우DEM적파면경류법시최위상용적수계제취방법，기제취정도직접취결우DEM중와지적처리방법。위료비교불동DEM처리방법대수계제취정도적영향，본문이강서성로하류역위례，이용기우DEM수거적J＆D산법급기우보조수거적AGREE방법래처리실험구DEM，연후이용파면경류법제취수계。결과표명，경량충방법후균가이제취출련속적수계，차제취수계적등급、수량급장도상차불대；재제취정도상，재수인류활동영향교소적산지구릉지구량충방법제취적수계비교문합，이재평탄지구혹수인류활동영향교대적지구제취적수계차이교대，차AGREE방법처리후제취적수계정도교고。
Water systems are not only important natural details, but also critical data sources for flood preven- tion, disaster reduction and exploitation of natural resources. Water systems are usually extracted from DEM （digital elevation data） with slope-runoff method, the accuracy of which is determined by the pro- cessing method of depressions in DEM. In order to study the effect of different DEM processing methods on the accuracy of extracted water system, we compared water systems extracted from DEM with two pro- cessing methods. In this study, DEM data based on J~d） algorithm and auxiliary data based on AGREE method were tested against 30 meter DEM for Liaohe River valley, Jiangxi Province. The results show that both of the methods are capable of extracting continuous drainage lines of similar orders, quantities and lengths. It revealed that the extracted water systems of two methods agree well in the steep mountain- ous region, but show large differences as for the well-populated flat area. Comparisons also demonstrated that the AGREE method enjoys high extraction accuracy than J＆D methods as for the flat area.