Probabilistic relations between acid–base chemistry and fish assemblages in streams of the western Adirondack Mountains, New York, USA

Barry P Baldigo,Douglas A Burns,Charles T Driscoll,Timothy J Sullivan,Shuai Shao,Scott D George,Gregory B Lawrence

doi:10.1139/cjfas-2018-0260

Abstract

Surface waters across much of New York’s Adirondack Mountains were acidified in the late 20th century but began to recover following the 1990 amendments to the Clean Air Act. Little data, however, are available to characterize biological impacts and predict recovery of fish assemblages in streams of the region. Quantitative fish and chemistry surveys were completed in 47 headwater streams during summer 2014–2016 to develop logistic (probabilistic) models that characterize the status of contemporary fish assemblages and predict how different nitrogen (N) and sulfur (S) deposition loads may affect future fish assemblages. Models for inorganic monomeric aluminum (Ali) and richness ≥1 species and for acid neutralizing capacity (ANC) and total density >400 fish/0.1 ha, total biomass >1500 g/0.1 ha, brook trout (Salvelinus fontinalis) density >0 or >200 fish/0.1 ha, and brook trout biomass >1000 g/0.1 ha were suitable for evaluating community and population responses to changes in acid–base chemistry. Anticipated changes in national (US) secondary standards for atmospheric emissions of nitrogen oxides (NOx) and sulfur oxides (SOx) to achieve target N and S deposition loads will alter acid–base chemistry and the probabilities for observing various levels of fish metrics in streams across the region and elsewhere.

Highlights

Acid deposition has declined precipitously across eastern North America (McHale et al.2017), subsequent improvements in water chemistry and biology of streams appear to be lagging considerably (Baldigo et al 2018a; Baldigo et al 2007; Lawrence et al 2011)
The curves for acid neutralizing capacity (ANC) (Fig. 1A), pH (Fig. 1D), and Ali (Fig. 1H) and corresponding equations (Table 1) for richness ≥2 species are suitable for predicting the response of fish communities to changes in acid-base chemistry of streams given that streams with
The curves for both ≥1 and ≥2 species (Fig. 1H) covered the full range of Ali concentrations observed during summers in all study streams (0 to 4 μmol L-1) and were not highly imbalanced (Table 1)

Summary

Introduction

Acid deposition has declined precipitously across eastern North America (McHale et al.2017), subsequent improvements in water chemistry and biology of streams appear to be lagging considerably (Baldigo et al 2018a; Baldigo et al 2007; Lawrence et al 2011). With two notable exceptions (Josephson et al 2014; Sutherland et al 2015), anticipated improvements in the health of aquatic species from acidified streams or lakes of the region have not occurred on a broad scale (Baldigo et al 2016; Simonin et al 2005). These observations suggest that limited biological recovery is occurring, but that the process is slow

Methods

Results

Conclusion