Does a copper-nitrate synergy drive algal blooms and toxicity in Sierra Nevada Lakes?
August 2020 - July 2024
- USGS Science Support Partnership
Using a recently developed, web-based, mapping tool, collaborators at Sequoia and Kings Canyon National Parks (SEKI) and the University of California, Davis Agricultural GIS Laboratory calculated predicted pesticide deposition, moving from agricultural lands in California’s Central Valley into California national parks (Meyer and DeMars, 2018; UC-Davis 2019).
From this analysis, the mapping tool identified copper-based pesticides among the top three high-impact pollutants that are likely to enter SEKI’s oligotrophic mountain lakes by atmospheric deposition (Fig. 1). In addition to copper, agricultural activities are likely the main source of volatized nitrogen in the atmosphere over SEKI (Fig. 1) (Almaraz et al., 2018). Derived from fertilizers and manure, the atmospheric nitrogen drives algal blooms in SEKI’s lakes (Barron and Nydick 2018), and contributes significantly to smog (Almaraz et al., 2018), despite the park being designated a “Class I” area, intended by the Clean Air Act to receive the highest level of air quality protection.