1989 Land Cover/Use Data for the Upper Mississippi River System--Pool 1

The U.S. Geological Survey's Upper Midwest Environmental Sciences Center (UMESC) has created high-resolution land cover/use data sets for the Upper Mississippi River System (UMRS) from 1:15,000-scale color infrared aerial photos collected in 1989. The data are available in two formats. The first used a detailed genus-level classification scheme and was used to classify Mississippi River Navigation Pools 4 through 26, the Open River between Grand Tower and River Mile 32, and the Peoria navigation Pool on the Illinois River. The second classification scheme was developed in 1998 in response to a scientific and programmatic review of the center's mapping projects. This classification scheme identifies plant communities and associations. This second classification scheme was used to interpret data for Mississippi River Pools 1 through 3, the Open River between Lock and Dam 26 and Grand Tower, and the Alton, Starved Rock, Marseilles, Brandon, Dresden, and Lockport navigation pools on the Illinois River. At the time this metadata document was prepared data classified underneath the first classification scheme were being cross-walked to the new scheme. This metadata document has been prepared to document the second classification scheme.美国地质调查局（U.S. Geological Survey）中西部上游环境科学中心（Upper Midwest Environmental Sciences Center, UMESC）基于1989年采集的1:15000比例尺彩红外航空影像，为上密西西比河系统（Upper Mississippi River System, UMRS）构建了高分辨率土地覆盖/利用数据集。该数据集包含两种格式版本：其一采用精细的属级分类方案，曾用于密西西比河通航渠段4号至26号、大塔（Grand Tower）至河道里程32号区间的开放河段，以及伊利诺伊河皮奥里亚通航渠段的分类解译工作。其二分类体系于1998年研发，以响应该中心测绘项目的科学与项目审查要求，该体系可识别植物群落与群丛，曾用于解译密西西比河通航渠段1号至3号、26号船闸大坝至大塔区间的开放河段，以及伊利诺伊河上奥尔顿、斯塔韦德罗克（Starved Rock）、马赛勒斯（Marseilles）、布兰登（Brandon）、德累斯顿（Dresden）与洛克波特（Lockport）等通航渠段的数据。在本元数据（metadata）文档编制之际，采用第一种分类体系的分类数据正被跨标准映射至新的分类体系。本元数据文档旨在对第二种分类体系进行文档化说明。