Assessing Acid‐Sensitive Lakes in the Superior National Forest

Abstract

This collaboration between the Superior National Forest unit of the US Forest Service (USFS SNF) and the University of Minnesota Duluth’s Natural Resources Research Institute (NRRI) began in late 2015 and has continued since. Initial discussions, with additional input from MPCA staff, led to four main goals, all intended to increase SNF’s long-term ability to determine the present condition of their lakes and if statistically significant trends exist: (1) Assess the current water quality – in particular, the acid neutralizing capacity (ANC) – of three SNF study lakes in northeastern Minnesota by analyzing a suite of major ions and nutrients in samples collected by FS staff; (2) Compile available historical SNF lake water quality data, assure the quality of these data, and then combine them into a searchable database; (3) Conduct exploratory statistical analyses to identify long-term trends in any of the datasets; and (4) Compare SNF lake summary statistics to those for lakes within the broader Upper Midwest ecoregion determined by the US EPA National Lakes Assessment (NLA) and by the Minnesota Pollution Control Agency (MPCA) for the Laurentian mixed forest (# 212) province.