Gathered all nutrient data from HUC 07 since 1979. These are all the nutrient parameters available (108). .... several million data points
Used R package packages DataRetrieval and EGRET and dplyr
Follow steps in this USGS report, harmonizing data. General process outlined in image below.
https://pubs.er.usgs.gov/publication/sir20175006
Evaluate Parameters to use in trend analysis
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