Effects of forest fire and drought on acidity of a base-poor boreal forest stream: similarities between climatic warming and acidic precipitation

For cations generally, a pattern of general increase occurred across biomes, but not in all cases.

“For cations generally, this pattern of a general increase occurred across biomes (Bayley et al., 1992; Beche et al., 2005; Betts & Jones, 2009; Bitner et al., 2001; Burke et al., 2013; Murphy et al., 2018), but not in all cases.”

In cases where the buffering capacity was low, decreases in pH observed in the literature were attributed to acidity from export of reduced sulfur and subsequent oxidation, increased nitrate, application of phosphorus-based fire retardant, and increased DOC that included organic acids.

“In cases where the buffering capacity was low, decreases in pH observed in the literature were attributed to acidity from export of reduced sulfur and subsequent oxidation (Bayley et al., 1992), increased nitrate (Crilly et al., 2017), application of phosphorus-based fire retardant (Angeler et al., 2004, 2005, 2006) and increased DOC that included organic acids (Bladon et al., 2014).”

Elevated sulfate concentrations were most often associated with responses in boreal/peatland region lakes, but elevated sulfate has also been observed in temperate streams.

“Elevated sulfate concentrations were most often associated with responses in boreal/peatland region lakes (Bayley et al., 1992; Brown et al., 2013; Crilly et al., 2017; Lydersen et al., 2014), but elevated sulfate has also been observed in temperate streams (Beche et al., 2005).”

Alkalinity decreases in boreal regions have been attributed both to peatland release of hydrogen ions as well as oxidation of reduced sulfur.

“and this has been attributed both to peatland release of hydrogen ions as well as oxidation of reduced sulfur (Allen et al., 2003; Bayley et al., 1992; Crilly et al., 2017; Lydersen et al., 2014).”