High-Resolution Simultaneous Measurements of Dissolved Reactive Phosphorus and Dissolved Sulfide: The First Observation of Their Simultaneous Release in Sediments
High-Resolution Simultaneous Measurements of Dissolved Reactive Phosphorus and Dissolved Sulfide: The First Observation of Their Simultaneous Release in Sediments
复制标题
高分辨率同时测量溶解的活性磷和溶解的硫化物：首次观察到它们在沉积物中同时释放
DOI：
10.1021/es301134h
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发表时间：
2012-08-07
影响因子：
11.4
通讯作者：
Zhang, Chaosheng
中科院分区：
文献类型：
--
作者：
Ding, Shiming;Sun, Qin;Zhang, Chaosheng
沉积物中环境过程的重新评价依赖于在小尺度和同一地点捕获元素的非均质特征。在本研究中，开发了薄膜扩散梯度（DGT）技术，用于高分辨率同时测量溶解活性磷（DRP）和溶解硫化物。DGT技术中使用了一种新的结合凝胶，将AgI颗粒掺入之前用于DRP DGT测量的氧化锆结合凝胶中制备。通过常规程序和计算机成像密度测定（CID）技术分别测定装载到结合凝胶中的DRP和硫化物的浓度。在实验室条件下测试了DGT技术的性能，并将其应用于浅湖沉积物的原位测量。在直径约为3 mm的硫化物微微孔和长度超过1 cm的局部聚集带中，可以观察到DRP和溶解硫化物的同时释放，这是由于沉积物中活性有机质区中Fe（III）和硫酸盐的同时还原以及铁结合P的释放。该技术的良好性能意味着有一个巨大的潜力发展新的DGT技术，能够同时测量更多的分析物。
The reassessments of environmental processes in sediments rely upon capturing the heterogeneous features of elements at a small scale and at the same location. In this study, a diffusive gradients in thin films (DGT) technique was developed for the high-resolution simultaneous measurements of dissolved reactive phosphorus (DRP) and dissolved sulfide. A new binding gel was used in this DGT technique, which was prepared by incorporating AgI particles into the zirconium oxide binding gel previously used in the DGT measurement of DRP. The concentrations of the DRP and sulfide loaded into the binding gel were determined by a routine procedure and a computer-imaging densitometry (CID) technique, respectively. The performance of this DGT technique was tested under laboratory conditions and applied to in situ measurements in sediments of a shallow lake. Simultaneous release of DRP and dissolved sulfide was observed in a sulfide microniche with a diameter of similar to 3 mm and in locally aggregated zones with a length over 1 cm, which was attributed to the simultaneous reductions of Fe(III) and sulfate and the associated release of Fe-bound P in the zones of the reactive organic matter in sediments. The good performance of this technique implies that there is a great potential for the development of new DGT techniques capable of simultaneous measurements of more analytes.