Wetlands (National Wetlands Inventory)

Wetlands delineated via the U.S. Fish and Wildlife Service’s national standardized protocols using aerial imagery from 1981-1994 and 2013. The aerial extent, approximate location, and type of wetlands, surface waters, and deepwater habitats in the conterminous United States are mapped as defined by Cowardin et al. (1979). Not all wetland habitats are represented due to limitations with aerial imagery. The US Fish & Wildlife Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. These digital data files are records of wetland location and classification as defined by the U.S. Fish and Wildlife Service's National Wetlands Inventory (USFWS NWI) program. Visit the USFWS NWI program for classification scheme details: https://www.fws.gov/program/national-wetlands-inventory/classification-codes This layer is derived from a wetland layer created by the US Fish and Wildlife Service’s National Wetlands Inventory. The most recent publicly available version of this layer is accessible at: Download Seamless Wetlands Data by State | U.S. Fish & Wildlife Service (Maryland download layer) The data provide consultants, planners, and resource managers with information on wetland location and type. The data were collected to augment the efforts of Maryland's regulatory wetland management programs and to assist in resource management efforts such as the Chesapeake Bay Program and the Coastal Zone Management Program. These data are to be used for guidance purposes only. For more information, contact: GIS Manager Information Technology & Innovation (ITI) Montgomery County Planning Department, MNCPPC T: 301-650-5620本数据集依据美国鱼类及野生动物管理局（U.S. Fish and Wildlife Service, USFWS）的国家级标准化规程，采用1981-1994年及2013年的航空影像完成湿地勾绘。本数据集按照考尔丁等（Cowardin et al., 1979）制定的分类标准，对美国本土的湿地、地表水及深水生境的航空覆盖范围、大致位置与类型进行了制图。受航空影像局限性影响，本数据集未能覆盖全部湿地生境。美国鱼类及野生动物管理局同时排除了两类“人工养殖湿地”：一类符合《食品安全法案》（Food Security Act）的定义，另一类与考尔丁等提出的分类标准不符。本数字数据集为美国鱼类及野生动物管理局国家湿地清查（National Wetlands Inventory, NWI）项目所定义的湿地位置与分类记录。如需了解分类体系详情，请访问美国鱼类及野生动物管理局国家湿地清查项目页面：https://www.fws.gov/program/national-wetlands-inventory/classification-codes。本数据图层源自美国鱼类及野生动物管理局国家湿地清查项目生成的湿地图层。本图层最新公开版本的获取渠道为：按州下载无缝湿地数据 | 美国鱼类及野生动物管理局（马里兰州下载图层）。本数据集可为咨询顾问、规划人员与资源管理者提供湿地位置与类型相关信息。本数据集的采集旨在强化马里兰州合规湿地管理项目的工作成效，并助力切萨皮克湾项目、海岸带管理项目等资源管理工作的开展。本数据集仅可用于指导参考用途。如需获取更多信息，请联系：蒙哥马利县规划部信息技术与创新（Information Technology & Innovation, ITI）部门地理信息系统管理员，MNCPPC 电话：301-650-5620。