Abstract

Water and soil samples were collected from 40 lake basins in the Teton and Gros Ventre Wilderness areas of western Wyoming, USA in the summers of 2005 and 2006, respectively. Analysis of water samples led to a baseline for further sampling to determine levels of atmospheric NOx deposition. Acid Neutralization Capacity (ANC) of these lakes was used as an indicator of susceptibility to acidification from atmospheric deposition. Also examined was the contention that water quality is a function not only of air quality but also of abiotic and biotic characteristics of lake catchment basins. Interviews with 6 permitted outfitters were conducted in March 2008. These interviews generated a baseline of observed phenomena relating to Air Quality Related Values (AQRV’s) and the feasibility of using local, long-term resource users as a monitoring tool. Five lakes in each the Teton and Gros Ventre Wildernesses had less than 200μeq/L ANC. These ten lakes are at risk of acidification according to EPA guidelines. When integrated with the 1984 EPA Western Lakes Survey data, basic trends of air quality emerged. Increases in NH₄ ⁺ and decreases in SO₄^2- were shown. Parent material was found to have a significant correlation with ANC (p=0.007). The interview process showed that outfitters are a source for historic resource conditions and can prove to be a valuable part of the monitoring process by noticing visible changes in the resource.

Additional Key Words: nitrogen, wilderness, acid neutralization capacity, parent material, mixed methods. Subject Category: Air quality