Sampling locations in this study (circles) and monitoring stations (triangles) in northeastern USA.

<p>The base map shows the sum of dry and wet Hg deposition modeled by Yu et al. (2014).</p

Concentrations of Hg in foliage of dominant species at four sites in the northeastern USA.

<p>Tree species included American beech (BE), yellow birch (YB), red maple (RM), sugar maple (SM), red spruce (RS), white ash (WA), white pine (WP) and balsam fir (BF). Error bars represent the SE of Hg concentrations of three composited samples.</p

Four sites in the northeastern USA were used in this study.

<p>Four sites in the northeastern USA were used in this study.</p

Concentrations of Hg in bole wood of dominant species at four sites in the northeastern USA.

<p>Tree species included American beech (BE), yellow birch (YB), red maple (RM), sugar maple (SM), red spruce (RS), white ash (WA), white pine (WP) and balsam fir (BF). Error bars represent the SE of Hg concentrations of three composited samples.</p

Biomass and Hg content of foliage, bark and bole wood in hardwood and conifer stands in this study and three published studies.

<p>Biomass and Hg content of foliage, bark and bole wood in hardwood and conifer stands in this study and three published studies.</p

Concentrations of Hg in bark of dominant species at four sites in the northeastern USA.

<p>Tree species included American beech (BE), yellow birch (YB), red maple (RM), sugar maple (SM), red spruce (RS), white ash (WA), white pine (WP) and balsam fir (BF). Error bars represents the SE of Hg concentrations of three composited samples.</p

Appendix A. Texts summarizing the quality control and quality assurance (QA/QC) procedures and the method of estimating atmospheric Hg deposition.

Texts summarizing the quality control and quality assurance (QA/QC) procedures and the method of estimating atmospheric Hg deposition