Sprague River Oregon Floodplain 2000

The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S. Fish and Wildlife Service, the USGS and University of Oregon conducted a study to evaluate channel and floodplain processes for the 131 km of the Sprague River and its major tributaries, including the lower 20 km of the South Fork Sprague River, the lower 16 km of the North Fork Sprague River, and the lower 62 km of the Sycan River. The study involved multiple analyses, including assessments of historical channel change, riparian and floodplain vegetation, and surficial geology. To support these analyses, digital floodplain and channel maps were prepared from historic notes, maps, and aerial photos to depict channel and floodplain conditions at different times between 1866 and 2005. The geospatial database of current and historic channel and floodplain conditions will also enable evaluation of long-term trends pertaining to aquatic and riparian habitat conditions.斯普拉格河（Sprague River）的流域面积达4090平方公里，流经俄勒冈州中南部地区，最终汇入威廉姆森河（Williamson River）与上克拉马斯湖。本研究由美国地质调查局（USGS）与俄勒冈大学联合美国鱼类及野生动物管理局开展，针对131公里长的斯普拉格河及其主要支流的河道与漫滩过程进行评估，所涉支流包括南叉斯普拉格河下游20公里、北叉斯普拉格河下游16公里，以及赛坎河（Sycan River）下游62公里。研究包含多项分析内容，涵盖历史河道变迁评估、河岸与漫滩植被调查及表层地质（surficial geology）分析。为支撑上述分析工作，研究团队基于历史记录、纸质地图与航空影像制作了数字河道与漫滩地图，用以呈现1866年至2005年间不同时期的河道与漫滩状态。这套收录当前及历史时期河道与漫滩状况的地理空间数据库，还可用于评估与水生及河岸栖息地状况相关的长期变化趋势。