Strontium (Sr) is a chemical element that is often used as a tracer in hydrogeochemical studies, and is ubiquitously distributed as a radioactive contaminant in nuclear sites in the form of strontium-90 (Sr-90). At the interface between groundwater and surface water, wetlands possess unique hydrogeochemical properties whose impact on Sr transport has not been investigated thoroughly. In this study, the adsorption and desorption of Sr was investigated on six natural wetland substrates and two mixes of exogenous media and wetland sediment: winter and summer wetland sediments, decayed cattails, wood, leaf litter, moss, bone charcoal, and clinoptilolite. The composition of the organic matter was characterized using carbon-13, solid phase Nuclear Magnetic Resonance analysis. The range of the substrates’ adsorption coefficients obtained could be explained by factors indicative of proteins in the organic matter, which were shown to support strong and poorly reversible Sr adsorption. In contrast, the proportion of carbohydrates and lignin were found to be indicative of lower adsorption coefficients and higher desorption. The implications of these results for Sr pollution remediation in wetlands are discussed.

锶（Sr）是一种化学元素，在水文地球化学研究中经常用作示踪剂，并以放射性锶90（Sr-90）的形式作为放射性污染物普遍存在于核位置。在地下水和地表水之间的界面处，湿地具有独特的水文地球化学特性，其对Sr传输的影响尚未得到充分研究。在这项研究中，研究了Sr在六种天然湿地基质以及两种外源性介质和湿地沉积物混合物上的吸附和解吸：冬季和夏季湿地沉积物，腐朽的香蒲，木材，树叶凋落物，苔藓，骨炭和斜发沸石。使用碳13固相核磁共振分析法表征有机物的组成。所获得的底物吸附系数的范围可以由指示有机物中蛋白质的因素来解释，这些因素表明它们支持强而差的可逆Sr吸附。相反，发现碳水化合物和木质素的比例指示较低的吸附系数和较高的解吸。讨论了这些结果对湿地Sr污染修复的意义。