National Lakes Assessment 2012 Datafiles for Report “National Lakes Assessment 2012: A collaborative survey of lakes in the United States"

National Lakes Assessment 2012 Datafiles for Report “National Lakes Assessment 2012: A Collaborative Survey of lakes in the United States”: The National Lakes Assessment (NLA) is a statistical survey of the condition of our nation's lakes, ponds, and reservoirs. It is designed to provide information on the extent of lakes that support healthy biological condition and recreation, estimate how widespread major stressors are that impact lake quality, and provide insight into whether lakes nationwide are getting cleaner. This dataset is an archived (zipped) file comprised of chemical, physical and biological files used in developing the NLA 2012 report. Sampling was conducted in the summer of 2012 at approximately 1000 sites in the conterminous U.S. Sites were selected using a statistical survey (probabilistic) design. The files include water chemistry, profile data, benthic macroinvertebrates, physical habitat, landscape metrics, phytoplankton data, secchi depth, data, tropic status, zooplankton, etc. Users are encouraged to visit the NARS data webpage for updates to data files (e.g., for example updated zooplankton files) and data from other surveys. https://www.epa.gov/national-aquatic-resource-surveys/data-national-aquatic-resource-surveys Citation for the NLA 2012 archived data: U.S. Environmental Protection Agency. National Aquatic Resource Surveys. National Lakes Assessment 2012 Report. Archived Data. (INSERT data and metadata files used). Available from U.S. EPA web page: https://www.epa.gov/national-aquatic-resource-surveys/national-results-and-regional-highlights-national-lakes. DOI: 10.23719/1529584 EPA encourages users who are publishing subsets of the data (say as part of a journal article publication) to include the above citation. EPA also encourages users of the data to include the following acknowledgement: “The National Lakes Assessment 2012 data were a result of the collective efforts of dedicated field crews, laboratory staff, data management and quality control staff, analysts and many others from EPA, states, tribes, federal agencies, universities, and other organizations. Please contact [e-mail] with any questions.” Additional information: NLA is part of the National Aquatic Resource Surveys, an EPA/State/Tribal partnership. The National Aquatic Resource Surveys (NARS) are statistical surveys designed to assess the status of and changes in quality of the nation’s coastal waters, lakes and reservoirs, rivers and streams, and wetlands. Using sample sites selected at random, these surveys provide a snapshot of the overall condition of the nation’s water. Because the surveys use standardized field and lab methods, we can compare results from different parts of the country and between years.用于《2012年全国湖泊评估：美国湖泊协同调查》报告的2012年全国湖泊评估（National Lakes Assessment, NLA）数据集文件： 全国湖泊评估（National Lakes Assessment, NLA）是一项针对全美湖泊、池塘与水库健康状况的统计调查。其旨在提供支持健康生物状态与休闲功能的湖泊覆盖范围相关信息，评估影响湖泊水质的主要胁迫因子的分布广度，并洞察全美湖泊的水质是否正在改善。本数据集为归档压缩文件，包含用于编制2012年NLA报告的化学、物理及生物学相关数据文件。本次调查于2012年夏季在美国本土的约1000个采样点开展，采样点采用统计调查（概率抽样）设计进行选取。这些文件涵盖水化学、剖面数据、底栖大型无脊椎动物、物理生境、景观指数、浮游植物数据、赛氏盘透明度（Secchi depth）、营养状态、浮游动物等相关内容。鼓励用户访问国家水生资源调查（National Aquatic Resource Surveys, NARS）数据网页，以获取数据文件的更新内容（例如更新后的浮游动物数据文件）及其他调查的相关数据，网页地址：https://www.epa.gov/national-aquatic-resource-surveys/data-national-aquatic-resource-surveys。 2012年NLA归档数据的引用格式如下：美国环境保护署。国家水生资源调查。2012年全国湖泊评估报告。归档数据。（请填入所使用的数据与元数据文件）。可从美国EPA官网获取：https://www.epa.gov/national-aquatic-resource-surveys/national-results-and-regional-highlights-national-lakes。DOI：10.23719/1529584。 EPA鼓励将该数据子集用于发表（例如期刊文章发表）的用户采用上述引用格式。同时EPA也鼓励数据使用者附上以下致谢声明：“2012年全国湖泊评估数据是由EPA、各州、部落、联邦机构、高校及其他组织中的敬业野外人员、实验室工作人员、数据管理与质量控制人员、分析师以及众多其他参与者共同努力的成果。如有任何疑问，请联系[e-mail]。” 补充说明：NLA隶属于国家水生资源调查（National Aquatic Resource Surveys, NARS），该项目为EPA、各州与部落的合作项目。国家水生资源调查（NARS）是一类统计调查，旨在评估全美沿海水域、湖泊与水库、河流与溪流以及湿地的水质现状与变化趋势。这些调查通过随机选取采样点，能够呈现全国水体整体健康状况的快照。由于调查采用标准化的野外与实验室方法，因此可以对美国不同地区以及不同年份的调查结果进行对比。