Do lakes feel the burn? Ecological consequences of increasing exposure of lakes to fire in the continental United States

Nitrogen and phosphorus increases have also been reported for lakes in post-fire watersheds.

“Nitrogen and phosphorus increases have also been reported for lakes in post-fire watersheds (McCullough et al., 2019).”

Lakes also experience elevated inorganic chemical concentrations, including metals, following fires, but there was comparatively less information on elevated metals in lakes than in streams.

“Lakes also experience elevated inorganic chemical concentrations, including metals, following fires (McCullough et al., 2019; Smith et al., 2011), but there was comparatively less information on elevated metals in lakes than in streams.”

At least some organic carbon increases in aquatic ecosystems below burned watersheds, especially lakes, are likely attributable to algae.

“At least some organic carbon increases in aquatic ecosystems below burned watersheds, especially lakes, are likely attributable to algae.”

Wildfire-mediated nutrient enrichment can increase algal biomass and shift composition.

“Wildfire-mediated nutrient enrichment also can increase algal biomass and shift composition (Kelly et al., 2006; McCullough et al., 2019).”

Algal responses in lakes post-fire were variable, with some lakes experiencing increases and others not.

“Algal responses in lakes post-fire were variable as well, with some lakes experiencing increases and others not (Lewis et al., 2014; McCullough et al., 2019).”

Shifts in thermal regimes have also been observed in wetlands and lakes in burned watersheds, but both waterbody types have been understudied.

“Shifts in thermal regimes have also been observed in wetlands (Gu et al., 2008) and lakes in burned watersheds, but both of these waterbody types have been understudied (McCullough et al., 2019).”

Studies from lakes were similarly diverse in pH response.

“Studies from lakes were similarly diverse in pH response (McCullough et al., 2019).”

Lentic waterbodies would be expected to exhibit even greater effects given their higher residence time and slower reaeration.

“Lentic waterbodies would be expected to exhibit even greater effects given their higher residence time and slower reaeration (McCullough et al., 2019).”

Algal biomass in downstream lakes, especially oligotrophic lakes, often increased in response to dissolved nutrient export from burned watersheds and contributed organic carbon through exudation or lysis.

“Algal biomass in these downstream lakes, especially oligotrophic lakes, often increased in response to dissolved nutrient export from burned watersheds and contributed organic carbon through exudation or lysis (Allen et al., 2003, 2005; McCullough et al., 2019).”

Algal assemblages can be impacted by wildfire, both through changes in biomass and composition, depending on waterbody type, context, and timing.

“Algal assemblages can be impacted by wildfire, both through changes in biomass and composition, depending on waterbody type, context, and timing (Bixby et al., 2015; McCullough et al., 2019).”