Drought-induced release of metals from peatlands in watersheds recovering from historical metal and sulphur deposition
Drought-induced release of metals from peatlands in watersheds recovering from historical metal and sulphur deposition
复制标题
从历史金属和硫沉积中恢复的流域泥炭地中干旱引起的金属释放
作者：
E. Szkokan;B. Kielstra;S. Watmough;J. Gunn
据预测，气候变化将导致北方生态区干旱的频率和严重程度增加，这可能导致地下水位下降，随后从湿地释放出酸性、金属污染的沃茨。我们认为，在历史上金属和硫沉积严重的地区，这些间歇性的金属脉冲可能达到足够高的浓度，严重影响接收沃茨的水生群落，并导致生物恢复的延迟。本研究的目的是评估干旱对两个萨德伯里泥炭地排水化学的影响，泥炭有机质含量相差悬殊，以确定该地区泥炭地类型的河流水化学对干旱的响应。2011年6月至11月，使用ISCO™自动水收集器收集了河流样品。经过一段时间的干旱，有一个下降的pH值和硫酸盐和金属离子（铝，钴，铜，铁，锰，镍，锌）的浓度大幅增加排水两个泥炭地，极端浓度发生在一段时间内约两个星期。在该网站具有较高的泥炭有机质含量有增加的金属，具有高亲和力结合DOC（铝，铜，铁）在干旱的发病。这项研究表明，在两个网站，不同的金属和养分池的大小，水文和地形，干旱的显着反应，这表明该地区的大部分泥炭地的潜力，以体验这种反应。恢复水生生态系统和保护淡水资源的努力必须考虑到这些过程，因为在不断变化的气候中，生物地球化学循环的中断可能会变得更加普遍。
Climate change is predicted to cause an increase in frequency and severity of droughts in the boreal ecozone, which can result in the lowering of water tables and subsequent release of acidic, metal-contaminated waters from wetlands. We believe that in areas where historical deposition of metals and sulphur was severe, these episodic pulses of metals could reach concentrations sufficiently high to severely affect aquatic communities in receiving waters and cause a delay in biological recovery. The objective of this study is to evaluate the impact of drought on the chemistry of water draining from two Sudbury peatlands with widely contrasting peat organic matter content to determine the response of stream water chemistry to drought from peatland types in the region. Stream samples were collected using ISCO™ automated water collectors from June to November 2011. Following a period of drought, there was a decline in pH and a large increase in concentrations of sulphate and metal ions (Al, Co, Cu, Fe, Mn, Ni, and Zn) in water draining both peatlands, with extreme concentrations occurring over a period of about two weeks. At the site with the higher peat organic matter content there was an increase in metals that have a high affinity to bind to DOC (Al, Cu, and Fe) during the onset of drought. This study demonstrates a dramatic response to drought at two sites that differ in metal and nutrient pool sizes, hydrology, and topography, suggesting the potential for a majority of peatlands in the region to experience this response. Efforts to restore aquatic ecosystems and protect freshwater resources must take into account these processes, as disruptions to biogeochemical cycles are likely to become more prevalent in a changing climate.
影响因子：
11.6
作者：
Evans, Christopher D.;Chapman, Pippa J.;Cresser, Malcolm S.
通讯作者：
Cresser, Malcolm S.