Hilsenhoff Biotic Index

quantiles

not measured
lo

med
hi

9-level aggregated ecoregion ^ x "



	 NPL ,"' 'V



SPL '' lr



	 TPL '' _/r



-- WMT / J



xer ry



¦ ' ii -/r



' H 1 P-_



2	4	6	8

Hilsenhoff Biotic Index

Source: www.epa.gov/bioiweb1/statprimer/

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