Seasonal Changes of Escherichia coli Concentrations in Iowa Watersheds
The following six change maps show seasonal variation in the increases and decreases in the levels of E.coli in Iowa watersheds. The first two correspond to the pre-planting season, the second two to the growing season, and the last two to the post-havest season. There is a lot of variation in E.coli concentration changes both spatially throughout the state and temporally throughout the seasons, indicating a complicated process that is not fully captured by one attribute.
Data from iowadnr.gov/aquia, maps by Miah Boyle.
April-May
Average change in E. coli concentration (MPN/100ml) of watershed units from April to May.May-June
Average change in E. coli concentration (MPN/100ml) of watershed units from May to June.
June-July
Average change in E. coli concentration (MPN/100ml) of watershed units from June to July.
July-August
Average change in E. coli concentration (MPN/100ml) of watershed units from July to August.
August-September
Average change in E. coli concentration (MPN/100ml) of watershed units from August to September.September-October
Average change in E. coli concentration (MPN/100ml) of watershed units from September to October.