Wildfires in the western United States are mobilizing PM_2.5-associated nutrients and may be contributing to downwind cyanobacteria blooms

Abstract

Wildfire activity is increasing in the continental U.S. and can be linked to climate change effects, including rising temperatures and more frequent drought conditions. Wildfire emissions and large fire frequency...

Effects of Air Pollutants from Wildfires on Downwind Ecosystems: Observations, Knowledge Gaps, and Questions for Assessing Risk

“…In Montana, increases in stream ammonium, nitrate, and phosphorus (P) were observed, associated with downwind wildfire exposure. , The increase was linked to gas diffusion and deposited ash given the lack of runoff, and these pathways were confirmed experimentally. In several lakes in California, downwind nutrient increases were not observed, although increased primary producer responses were noted, potentially masking a measured nutrient response. , Beyond nutrients, other reported effects include declines in dissolved oxygen following exposure to downwind fire emissions, presumably due to lower light and increased oxygen demand from deposited loads, and increases in metals and PAHs in lake sediments downwind of fires. , …”

Wildfires Increase Concentrations of Hazardous Air Pollutants in Downwind Communities

“…We conducted a nonparametric permutation test to test whether concentrations were higher on smoke days compared with nonsmoke days (i.e., testing the null hypothesis that there were no differences) both with all years grouped together and each year individually from 2006 to 2020. This analysis was adapted from previously published methods. , This nonparametric test was selected for multiple reasons, including an unequal number of samples from smoke and nonsmoke days, and skewed concentration distributions. Observations were excluded in cases where the following conditions were not met at an individual monitor in a single year: (1) at least 20 measurements overall and (2) at least four measurements labeled as smoke-impacted.…”

“…This analysis was adapted from previously published methods. 12,37 This nonparametric test was selected for multiple reasons, including an unequal number of samples from smoke and nonsmoke days, and skewed concentration distributions. Observations were excluded in cases where the following conditions were not met at an individual monitor in a single year: (1) at least 20 measurements overall and (2) at least four measurements labeled as smoke-impacted.…”

Chemical Binder-Free and Oven-Dried Lignocellulose/Clay Composite Foams: Flame Resistance, Thermal Insulation, and Recyclability

“…They serve as a physical barrier to inhibit heat transfer, impede the contact of the substrate with air, and mitigate the generation and spread of flammable volatiles, which promotes the composite’s flame resistance . Moreover, the absence of nitrogen and phosphate elements allows clay to be free from eutrophication concerns, making it an environmentally benign option, among others . However, the interaction between clay and lignocellulose is generally weak, making it difficult to robustly integrate a large quantity of clay into the host matrix.…”

“…41 Moreover, the absence of nitrogen and phosphate elements allows clay to be free from eutrophication concerns, making it an environmentally benign option, among others. 42 However, the interaction between clay and lignocellulose is generally weak, making it difficult to robustly integrate a large quantity of clay into the host matrix. Recently developed methods include the use of dissolved cellulose and chemical cross-linker to promote its binding with clay particles, 33 which unfortunately required massive use of the dissolving medium and limited the downstream chemical recycling/regeneration (i.e., separation, purification, and concentration).…”