一、森林对水文特性的影响为了说明黄河中游西北黄土高原森林对水文特性的影响,本文着重分析了北洛河上游干流刘家河水文站与支流葫芦河张村驿水文站的历年测验资料。刘家河水文站控制流域面积为7300平方公里,是北洛河的源头,位置偏于西北,与马连河西川及无定河上游同属黄河流域有名的严重侵蚀与粗颗粒泥沙来源的白玉山河 I. THE EFFECT OF FOREST ON HYDROLOGICAL CHARACTERISTICS In order to illustrate the influence of forests on the hydrological characteristics in the northwestern Loess Plateau in the middle reaches of the Yellow River, this paper analyzes empirically the historical data of the Liujiahe hydrological station and the Zhangcunyi Hydrometric Station in the upper reaches of the northern Luohe River. Liujiahe hydrological station control basin area of ​​7,300 square kilometers, is the source of the North Luo River, the location is located in the northwest, and the upper reaches of the Malian River and Wudinghe belong to the Yellow River Basin, a well-known source of serious erosion and coarse sediment Baiyu Mountain