Iowa DNR
BioNet
River & Stream Biological Monitoring
Fish and Benthic Macroinvertebrate Surveys
Physical Habitat Assessments

Iowa's Ecoregions


Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources.

An ecoregion is identified through patterns and composition of both biological and physical characteristics, including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology.

The interactions and relative importance of each of these components varies between ecoregions, creating a unique ecosystem within each region.

Combined with a network of wadeable reference sites, ecoregions provide a framework for stream biological assessment, allowing researchers, watershed coordinators, and others interested in watershed improvement to make certain assumptions and predictions about the relative health of streams within an ecoregion.

There are 10 ecoregions and subecoregions within the state of Iowa:

Wadeable Reference Site FIBI Warm Water Results

Eco Desig Eco Name Min 25th Percentile Mean Median 75th Percentile Max Total Samples
40a Loess Flats and Till Plains 16 33 39.26 40 47 63 34
47a Northwest Iowa Loess Prairies 35 42 46.96 44.5 51 62 24
47b Des Moines Lobe 13 38 50.22 52 61 85 104
47c Iowan Surface 27 60 66.51 69 77 92 105
47d Missouri Alluvial Plain No reference sites 0
47e Steeply Rolling Loess Prairies 12 28.5 36.08 35.5 43.5 65 26
47f Rolling Loess Prairies 3 35 44.91 45 55 80 92
47m Western Loess Hills No reference sites 0
52b Paleozoic Plateau (Driftless Area) 14 49.5 56.78 56 65 87 72
72d Upper Mississippi Alluvial Plain 20 36 39.67 38 48 54 9

Wadeable Reference Site BMIBI Warm Water Results

Eco Desig Eco Name Min 25th Percentile Mean Median 75th Percentile Max Total Samples
40a Loess Flats and Till Plains 14 39.25 48.18 50.5 57.75 77 34
47a Northwest Iowa Loess Prairies 10 46.25 53.19 51.5 59.5 88 26
47b Des Moines Lobe 10 50 59.11 62 69 84 105
47c Iowan Surface 23 56 65.31 68 75 91 107
47d Missouri Alluvial Plain No reference sites 0
47e Steeply Rolling Loess Prairies 34 49 55.67 56 64 72 27
47f Rolling Loess Prairies 19 54 60.25 61 69 86 91
47m Western Loess Hills No reference sites 0
52b Paleozoic Plateau (Driftless Area) 52 63.5 70.5 71 78.25 84 32
72d Upper Mississippi Alluvial Plain 20 38 46.11 42 54 76 9

Wadeable Reference Site BMIBI Cold Water Results

Eco Desig Eco Name Min 25th Percentile Mean Median 75th Percentile Max Total Samples
47c Iowan Surface No reference sites 0
47f Rolling Loess Prairies No reference sites 0
52b Paleozoic Plateau (Driftless Area) 42 60 69.2 71 78 92 71