LTRMP Fisheries Data - Stratified Random and Fixed Site Sampling

The Long Term Resource Monitoring Programs (LTRMP) annual fish monitoring began on the Upper Mississippi and Illinois Rivers in 1989. During the first two years samples were collected at a series of fixed sampling sites, then in 1993 a stratified random sampling approach was added to the collection effort. This approach utilizes a computer routine that randomly selects sampling sites from a pool of potential sites that have been categorized by strata (e.g., aquatic habitat type, distance to shore, connectivity to main channel). The results from these collections are stored in an Oracle database at the Upper Midwest Environmental Science Center (UMESC). UMESC provides free access to the data through the Centers Web site (www.umesc.usgs.gov). Several methods/routines are available for accessing the data (e.g., graphical browser, GIS query tool) this particular file is designed to accompany the main Oracle database (http://www.umesc.usgs.gov/data_library/fisheries/fish_page.html).

长期资源监测计划（Long Term Resource Monitoring Programs, LTRMP）的年度鱼类监测工作于1989年在上密西西比河与伊利诺伊河正式启动。项目前两年仅通过一系列固定采样点位采集样本，1993年新增分层随机采样方法用于样本收集。该方法依托计算机程序，从已按分层规则（如水生栖息地类型、距岸距离、主河道连通性）划分的潜在采样点位池中随机选取采样点。本次采样获取的所有数据均存储于上中西部环境科学中心（Upper Midwest Environmental Science Center, UMESC）的Oracle数据库中。该中心通过其官方网站（www.umesc.usgs.gov）向公众免费开放数据访问权限。目前提供了多种数据访问途径（如图形化浏览器、地理信息系统查询工具），本数据集文件专为配套主Oracle数据库设计，配套页面的访问地址为http://www.umesc.usgs.gov/data_library/fisheries/fish_page.html。