Level III Ecoregions of EPA Region 9

Ecoregions for EPA Administrative Regions were extracted from the seamless national shapefile. Ecoregions denote areas of general similarity in ecosystems and in the...针对美国环境保护署（EPA）行政区域的生态区，从无缝全国形状文件（shapefile）中提取得到。生态区指代生态系统及……方面具备整体相似性的区域。