Level III Ecoregions of EPA Region 2

Ecoregions by EPA region were extracted from the seamless national shapefile. Ecoregions denote areas of general similarity in ecosystems and in the type, quality,...按美国环境保护署（Environmental Protection Agency，EPA）分区的生态区，提取自无缝隙全国形状文件（shapefile）。生态区指生态系统、生态类型与质量等方面具有总体相似性的区域。