Headwater Stream Spatial Dataset Field Site Map

Study areas for field data collection were selected to represent several EPA Level IV ecoregions (Griffith et al., 2002) with the number of sites per ecoregion based on the size the ecoregion (below). Since EPA Level IV Ecoregions are intended to represent landscapes with similar geology, topography and vegetation, sites were stratified by ecoregion given the assumption that ecoregions will help with control for landscape variability. Study watershed sizes ranged from 150 to 5500 acres in size and average of 40 stream origins (intermittent and perennial) per site.