The Columbia River Estuary Ecosystem Classification (Classification) is a spatially-explicit, GIS-facilitated system for classifying and mapping landforms and ecosystems of the Columbia River estuary. Working with USGS and the Lower Columbia Estuary Partnership, we have developed a six level hierarchical mapping structure. From coarse to fine, these six levels are: (1) ecosystem province, (2) ecoregion, (3) hydrogeomorphic reach, (4) ecosystem complex, (5) geomorphic catena, and (6) biocatena. Categories within each of these hierarchical levels reflect formative tectonic, geologic, hydrologic, biologic, or other processes at relevant temporal and spatial scales. Classification levels 1 and 2 derive from existing ecological mapping. Levels 3–6 are from new mapping and analysis. The Classification is intended to facilitate conservation planning, research, and monitoring.
For additional information, please see the USGS Open-File Report 2011-1228: Columbia River Estuary Ecosystem Classification – Concept and Application. link to pdf
The geodatabase and geospatial methodology are available through the USGS Water Resources NSDI Node. link to data