1989 Land Cover/Use Data for the Upper Mississippi River System--Pool 18

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）下属的中西部上游环境科学中心（Upper Midwest Environmental Sciences Center, UMESC）依托1989年采集的1:15000比例尺彩红外航空照片，构建了针对密西西比河上游水系（Upper Mississippi River System, UMRS）的高分辨率土地覆盖/利用数据集。该数据集以两种格式提供，分别对应两套分类体系：其一采用精细化的属级分类方案，曾用于对密西西比河通航渠段4至26号、格兰德塔至河程32英里之间的开放河道，以及伊利诺伊河上的皮奥里亚通航渠段开展分类标注。其二为1998年制定的分类体系，该体系旨在响应该中心测绘项目的科学与项目审查需求，可识别植物群落与群丛，被用于解读密西西比河1至3号渠段、26号船闸大坝至格兰德塔之间的开放河道，以及伊利诺伊河上的奥尔顿、斯塔德罗克、马赛尔斯、布兰登、德累斯顿与洛克波特通航渠段的相关数据。在本元数据（metadata）文档编制之际，采用第一种分类体系标注的数据正被跨体系转换适配至新的分类方案。本元数据文档旨在对第二种分类体系进行完整归档说明。