Posteruptive impacts of pyroclastic deposits from basaltic andesite stratovolcanoes on surface water composition
Posteruptive impacts of pyroclastic deposits from basaltic andesite stratovolcanoes on surface water composition
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玄武质安山岩成层火山火山碎屑沉积物对地表水成分的影响
DOI：
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
R. Donahoe
中科院分区：
文献类型：
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作者：
K. Genareau;S. Cronin;C. Stewart;S. Bhattacharyya;R. Donahoe
爆炸性喷发后的火山灰沉积可能对水质、人类健康、农业和基础设施功能造成重大危害。许多研究都研究了新鲜的火山灰沉积如何降低暴露的地表水的 pH 值，并向暴露的地表水引入一系列潜在有毒元素。然而，尚未有研究确定机械火山碎屑分解以及新的新鲜颗粒表面和越来越细粒颗粒的产生对水成分的影响。这种分解可能是由于自然后过程（例如碎片雪崩、火山泥流或河流/风成运输）以及人类活动（例如清理工作或火山碎屑矿床的开采）造成的。火山碎屑分解的喷发后时间尺度可能有所不同，从潮湿的热带或温带环境中的几个月到干旱环境中的几年或几十年。在这里，我们在实验研究中首次表明，火山碎屑的机械研磨会将一系列元素引入暴露的水中，包括铝（在高浓度下可能有毒）和钠（会增加溶液的电导率）。浸出液的 pH 值也增加了几个 log 单位。实验规模上的这种巨大变化可能会对火山喷发后环境中的地表水组成产生影响，需要对生态系统健康进行长期风险评估，并考虑火山碎屑沉积物在火山活动区域元素循环中的作用。
Volcanic ash deposition following explosive eruptions can pose significant hazards for water quality, human health, agriculture, and infrastructure functionality. Many studies have examined how fresh ash deposition may lower the pH of, and introduce a range of potentially toxic elements into, exposed surface waters. However, no study has yet determined the effects on water composition as a result of mechanical pyroclast disaggregation and production of new fresh particle surfaces and increasingly fine grained particles. Such disaggregation could result from natural posteruptive processes such as debris avalanches, lahars, or fluvial/aeolian transport and human activities such as cleanup efforts or mining of pyroclastic deposits. The posteruption time scales of pyroclast disaggregation may vary from months in moist tropical or temperate environments to years or decades in arid settings. Here we show, for the first time in experimental studies, that mechanical milling of pyroclasts will introduce a range of elements into exposed waters, including Al, which can be toxic at elevated levels, and Na, which increases the electrical conductivity of solutions. The pH of leaching solutions also increases by several log units. Such dramatic changes on the experimental scale may have implications for surface water composition in posteruptive settings, necessitating longer‐term risk assessments for ecosystem health and consideration of the role of pyroclastic deposits in element cycling in volcanically active regions.
2010 年默拉皮火山百年喷发产生的火山灰对呼吸道健康的危害及其对矿床职业开采的影响
影响因子：
2.9
作者：
Damby D
通讯作者：
Damby D