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河溪结构及其关联的空间特征，是研究集水区中能量和物质移动规律所不可缺少的内容。利用美国地质调查局的水文数据库和地理信息系统（ＡＲＣ／ＩＮＦＯ），对美国大陆５个主要山地中典型集水区河溪的数量、密度、分布结构以及河溪岸边带的组成，进行了分析和比较。５个山地分别是：西北太平洋沿岸，西部卡斯卡特山，中部落矶山，东部阿巴拉契亚山和南部欧扎克山。发现这５个集水区中的河溪网络结构非常相似，一级河溪大约占河溪总长度的６０％左右。东部山地地质历史比较长，其集水区中河溪总长度、密度，高差以及河溪片段数量，都比西部相对年轻的集水区要高。此外，尽管其中河溪边岸域总面积随边岸域宽度线性增长，但它们在面积中的相对比例仍然很小（＜１２％）。因此，在森林经营中保护河溪边岸植被，并不会对木材生产造成太大的威胁
The river structure and its associated spatial features are indispensable for studying the law of energy and material movement in water catchments. Using the US Geological Survey hydrological database and geographic information system (ARC / INFO), the number, density, distribution structure and composition of the riverbanks in the typical catchments of the five main mountain areas in the continental United States Analysis and comparison. The five mountains are: the Pacific Northwest Coast, western Cascat, the Central Rocky Mountains, the Appalachian Mountains in the east and the southern Ozarks. It is found that the river networks in these five catchments are very similar in structure. The first grade of rivers accounts for about 60% of the total length of the river. The geological history of the eastern mountainous regions is relatively long. The total length, density, height difference and the number of river brooks in the catchment are higher than those in the relatively young western catchment. In addition, although the total area of riverbanks along the riverbank increases linearly with the width of the bank, their relative proportions in the area are still small (<12%). Therefore, protecting the vegetation along river banks in forest management will not pose a significant threat to timber production