Center for Air Resources Engineering and Science, Clarkson University, Potsdam 13699, NY, United States.
Department of Civil and Environmental Engineering, Clarkson University, Potsdam 13699, NY, United States.
Sci Total Environ. 2018 Oct 1;637-638:943-953. doi: 10.1016/j.scitotenv.2018.05.047. Epub 2018 May 12.
Measurements of ambient speciated mercury (Hg) concentrations and Hg wet deposition were made at two urban sites (Bronx, NY and Rochester, NY) and one rural site (Potsdam, NY) in New York State in 2013 and 2014 to: 1) determine the factors influencing Hg wet deposition concentrations, 2) identify the contribution of gaseous oxidized Hg (GOM) and particulate bound Hg (PBM) scavenging to Hg wet deposition concentrations, and 3) identify potential source areas associated with high concentration events. The Bronx had the highest mean gaseous elemental Hg (GEM) and GOM concentrations, Rochester had the highest mean PBM and the lowest GOM concentrations, and Potsdam had the lowest mean GEM and PBM concentrations. The annual volume weighted mean (VWM) Hg concentrations and Hg wet deposition fluxes in the Bronx, Rochester, and Potsdam were significantly different with mean values of 10.3 ± 8.16, 10.2 ± 9.06, and 5.07 ± 1.79 ngL and 8.45 ± 0.64, 6.65 ± 0.21, and 5.25 ± 0.49 μg/m year, respectively. Hg wet deposition flux and precipitation depth were positively correlated at all three sites as were Hg concentration in precipitation and weekly GOM concentrations at the Bronx and Potsdam sites. Scavenging coefficients (SC) of 680, 630, 850 for GOM and 410, 320, and 410 for PBM at Bronx, Rochester, and Potsdam, respectively, suggest GOM is responsible for most of the scavenged Hg. Measured GOM and PBM concentrations were relatively constant before precipitation events and Hg concentrations in precipitation did not vary significantly during precipitation events implying the scavenging process mainly occurred in clouds. VWM Hg concentrations, monthly accumulated Hg flux, and SCs for GOM and PBM were higher at the urban sites and significantly different for non-snow and snow events. Local sources appeared more important at the rural site while regional sources affected high urban concentrations.
2013 年和 2014 年，在美国纽约州的两个城市（布朗克斯，纽约和罗彻斯特，纽约）和一个农村（波茨坦，纽约）站点测量了环境形态汞（Hg）浓度和 Hg 湿沉降，以：1）确定影响 Hg 湿沉降浓度的因素，2）确定气态氧化汞（GOM）和颗粒结合汞（PBM）吸收对 Hg 湿沉降浓度的贡献，以及 3）识别与高浓度事件相关的潜在源区。布朗克斯的气态元素汞（GEM）和 GOM 浓度最高，罗彻斯特的 PBM 和 GOM 浓度最高，波茨坦的 GEM 和 PBM 浓度最低。布朗克斯、罗彻斯特和波茨丹的年体积加权平均值（VWM）Hg 浓度和 Hg 湿沉降通量差异显著，平均值分别为 10.3±8.16、10.2±9.06 和 5.07±1.79ngL 和 8.45±0.64、6.65±0.21 和 5.25±0.49μg/m 年。所有三个站点的 Hg 湿沉降通量和降水深度呈正相关，布朗克斯和波茨丹站点的降水 Hg 浓度和每周 GOM 浓度也呈正相关。布朗克斯、罗彻斯特和波茨丹的 GOM 和 PBM 的清除系数（SC）分别为 680、630、850 和 410、320、410，表明 GOM 是吸收 Hg 的主要成分。在降水事件之前，测量的 GOM 和 PBM 浓度相对稳定，降水期间降水 Hg 浓度没有明显变化，这意味着清除过程主要发生在云层中。VWM Hg 浓度、每月累积 Hg 通量和 GOM 和 PBM 的 SC 在城市站点更高，非雪和雪事件之间差异显著。本地来源在农村站点更为重要，而区域来源则影响城市高浓度。
