Increasing fish diversity of Chicago's waterways

Descriptions of shifts in biodiversity across time are desired for urban freshwater systems to better study ecosystem change and causal mechanisms. I document changes fish diversity within the Chicago Area Waterways 35 years using a battery metrics calculated on both abundance biomass data. Has Chicago's waterways changed over if so, do different exhibit trends or breakpoints trends? Diversity assemblage increased three decades study. Breakpoint analysis suggested that timeseries were nonlinear. Changes dominant species influenced behavior less traditional metrics, whereas Margalef's Richness, Shannon-Weiner, Gini-Simpson appeared more robust. Increases richness taxonomic combined with decreases dominance suggest an increasing quality. The community Waterway System is diverse as well ( i.e. , energy flows) late 2010's than it was 1980's. Although external factors related wastewater treatment water quality likely led these assemblage-level breakpoint did not allow verification