Abstract The partitioning of carbon dioxide (CO2) released by soils at Vulcano Island (Aeolian Islands, Italy) was performed by combining the CO2 flux and the carbon isotope measurements. Based on this method, the amount of CO2 of volcanic origin was quantified six times during the period 2015–2018. The data analysis allowed us to establish the correlation between CO2 soil degassing and changes in the contribution of volcanic fluids. Carbon isotope determinations were performed in situ to enhance the coverage of data collection in space and time. These data were combined with both the CO2 contents in the ground gases and the soil CO2 flux. The amount of volcanic CO2 was distinguished from that of biogenic origin by implementing a three-component mixing model. The results of this study indicate that the increase in CO2 output in September 2018 reflects the increase in volcanic gas emissions. The measurement method and analysis presented in this work are sufficiently general to be applicable to the monitoring programs of active volcanoes.

中文翻译：

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2015-2018 年 Vulcano（风神群岛）稳定同位素和扩散脱气调查揭示的深层 CO2 释放

摘要 通过结合 CO2 通量和碳同位素测量，对 Vulcano 岛（意大利伊奥利亚群岛）土壤释放的二氧化碳 (CO2) 进行分配。基于这种方法，在 2015-2018 年期间，火山起源的 CO2 量被量化了 6 次。数据分析使我们能够建立 CO2 土壤脱气与火山流体贡献变化之间的相关性。碳同位素测定是在原位进行的，以提高数据收集在空间和时间上的覆盖范围。这些数据与地面气体中的 CO2 含量和土壤 CO2 通量相结合。通过实施三组分混合模型，将火山 CO2 的量与生物源的 CO2 量区分开来。本研究结果表明，2018 年 9 月 CO2 产量的增加反映了火山气体排放量的增加。这项工作中提出的测量方法和分析足够通用，可适用于活火山的监测计划。