Habitat--Offshore of Point Reyes Map Map Area, California

This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Point Reyes map area, California. The vector data file is included in "Habitat_PointReyes.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePointReyes/data_catalog_OffshorePointReyes.html. Using multibeam echosounder (MBES) bathymetry and backscatter data, potential marine benthic habitat maps were constructed. The habitats were based on substrate types and documented or "ground truthed" using underwater video images and seafloor samples obtained by the USGS. These maps display various habitat types that range from flat, soft, unconsolidated sediment-covered seafloor to hard, deformed (folded), or highly rugose and differentially eroded bedrock exposures. Rugged, high-relief, rocky outcrops that have been eroded to form ledges and small caves are ideal habitat for rockfish (Sebastes spp.) and other bottom fish such as lingcod (Ophiodon elongatus). Habitat map is presented in a map format generated in a GIS (ArcMap), and both digital and hard-copy versions will be produced.DS 781的本部分提供了加利福尼亚州雷耶斯角近海制图区的海底生境地图相关数据。矢量数据文件已打包至"Habitat_PointReyes.zip"，可通过链接http://pubs.usgs.gov/ds/781/OffshorePointReyes/data_catalog_OffshorePointReyes.html获取。 本研究利用多波束测深声呐（multibeam echosounder, MBES）的水深测量与背散射数据，构建了潜在海洋底栖生境地图。该生境分类以底质类型为依据，并通过美国地质调查局（United States Geological Survey, USGS）获取的水下视频影像与海底样品完成地面实况验证。该地图涵盖多种生境类型，覆盖范围从平坦松软的未固结沉积物覆盖型海底，到坚硬、变形（褶皱）或高度崎岖且经差异侵蚀出露的基岩露头。经侵蚀形成岩架与小型洞穴的崎岖高起伏岩石露头，是岩鱼（Sebastes属，Sebastes spp.）以及蛇齿单线鱼（Ophiodon elongatus）等其他底栖鱼类的理想栖息生境。本生境地图采用地理信息系统（Geographic Information System, GIS，ArcMap）生成的制图格式制作，将同时提供数字版本与纸质印刷版本。