Lakes of Alaska with subsetting by watershed and SASAP region

Lakes of Alaska were analyzed by watershed and region of Alaska for the State of Alaska Salmon and People (SASAP) project. 188 watersheds and thirteen regions were assessed for number of intersecting lakes, area covered by lakes, and other lakes statistics as described in "Lake_Polygons.ipynb" in this package. Lakes data is based on the River Analysis Project (RAP) dataset as outlined in "A Riverscape Analysis Tool Developed to Assist Wild Salmon Conservation Across the North Pacific Rim" by Whited, D. C., J. S. Kimball, J. A. Lucotch, N. K. Maumenee, H. Wu, S. D. Chilcote, and J. A. Stanford (2012). Lakes polygons in the RAP dataset were provided directly by the authors (Waterbody_AK_RAP.zip) and are based on 1990s-era Landsat 4 and 5 satellite data, with methodology outlined in the publication above. More information on RAP can be found here: http://www.ntsg.umt.edu/rap/default.php. Regions are determined by the SASAP project and watersheds are based on HUC8 definitions from the International Joint Commission and sub-sub-drainages from the Canadian National Hydro Network.

为完成阿拉斯加州鲑鱼与人类（State of Alaska Salmon and People, SASAP）项目，本数据集按阿拉斯加的流域与区域对境内湖泊开展分析。本次评估共涵盖188个流域与13个区域，统计指标包括相交湖泊数量、湖泊覆盖面积及其他湖泊相关统计信息，相关细节详见本数据包内的"Lake_Polygons.ipynb"文件。湖泊数据源自河流分析项目（River Analysis Project, RAP）数据集，相关方法说明详见2012年由Whited, D. C.、J. S. Kimball、J. A. Lucotch、N. K. Maumenee、H. Wu、S. D. Chilcote及J. A. Stanford共同发表的论文"A Riverscape Analysis Tool Developed to Assist Wild Salmon Conservation Across the North Pacific Rim"。河流分析项目数据集中的湖泊多边形数据由该论文作者直接提供（压缩包文件为Waterbody_AK_RAP.zip），其数据基础为20世纪90年代的陆地卫星（Landsat）4号与5号卫星影像，具体研究方法详见上述发表论文。如需了解河流分析项目的更多信息，可访问以下网址：http://www.ntsg.umt.edu/rap/default.php。区域划分由SASAP项目制定，流域划分则基于联合国际委员会的8位水文单元分区（Hydrologic Unit Code 8, HUC8）标准，以及加拿大国家水文网络的次级子排水区数据。