Istituto Nazionale di Geofisica e Vulcanologia, sezione di Pisa, via della Faggiola, 32-56126 Pisa, Italy.
Istituto Nazionale di Geofisica e Vulcanologia, sezione di Palermo, via U. La Malfa, 153-90146 Palermo, Italy.
Environ Pollut. 2017 Dec;231(Pt 1):219-228. doi: 10.1016/j.envpol.2017.07.101. Epub 2017 Aug 10.
Sulfur dioxide (SO) is a major component of magmatic gas discharges. Once emitted in the atmosphere it can affect the air and land environment at different spatial and temporal scales, with harmful effects on human health and plant communities. We used a dense dataset of continuous SO flux and meteorological measurements collected at Vulcano over an 8-year period spanning from May 2008 to February 2016 to model air SO concentrations over the island. To this end, we adopted the DISGAS (DISpersion of GAS) numerical code coupled with the Diagnostic Wind Model (DWM). SO concentrations in air were determined for three different SO emission rates: a reference SO flux of ∼18 t/d (the median of more than 800 measurements), an enhanced SO flux of 40 t/d (average of all measurements plus 1 σ), and a maximum SO flux of 106 t/d (maximum value measured in the investigated period). Maximum SO concentrations in air were estimated at the crater, near the high-T fumarole field that is the source of the gas, and ranged from 2000 ppb to ∼24,000 ppb for the reference flux, from 2000 ppb to 51,000 ppb for the enhanced flux and from 5000 ppb to 136,000 ppb for the maximum flux, with peak values in limited areas at the bottom of the crater. These concentrations pose a hazard for people visiting the crater, for sensitive individuals in particular. Based on estimated SO concentrations in air, we also consider the phytotoxic effects of SO on local vegetation.
二氧化硫（SO）是岩浆气体排放的主要成分。一旦排放到大气中，它可以在不同的时空尺度上影响空气和陆地环境，对人类健康和植物群落产生有害影响。我们使用了一个密集的连续 SO 通量和气象测量数据集，该数据集是在 2008 年 5 月至 2016 年 2 月期间在 Vulcano 收集的，跨越了 8 年，用于模拟该岛上的空气 SO 浓度。为此，我们采用了 DISGAS（气体扩散）数值代码，该代码与诊断风模型（DWM）耦合。根据三种不同的 SO 排放率确定了空气中的 SO 浓度：约 18 t/d 的参考 SO 通量（800 多次测量的中位数）、40 t/d 的增强 SO 通量（所有测量值的平均值加 1 σ）和 106 t/d 的最大 SO 通量（研究期间测量的最大值）。在火山口，在气体源附近的高 T 喷气孔场附近，空气中的最大 SO 浓度估计值范围为 2000 ppb 至约 24,000 ppb，对于参考通量，从 2000 ppb 到 51,000 ppb，对于增强通量，从 5000 ppb 到 136,000 ppb，峰值值在火山口底部的有限区域。这些浓度对参观火山口的人，特别是对敏感个体构成了危害。基于空气中的 SO 浓度估计，我们还考虑了 SO 对当地植被的植物毒性影响。
