In situ measurement of redox sensitive solutes at high spatial resolution in a riverbed using Diffusive Equilibrium in Thin Films (DET)
In situ measurement of redox sensitive solutes at high spatial resolution in a riverbed using Diffusive Equilibrium in Thin Films (DET)
复制标题
使用薄膜扩散平衡 (DET) 以高空间分辨率原位测量河床中的氧化还原敏感溶质
DOI：
10.1016/j.ecoleng.2012.08.003
复制
发表时间：
2012
影响因子：
3.8
通讯作者：
M. Trimmer
中科院分区：
文献类型：
--
作者：
S. Ullah;Hao Zhang;A. Heathwaite;A. Binley;K. Lansdown;K. Heppell;M. Trimmer
在这里，我们评估了一种在粗河床沉积物中部署薄膜扩散平衡（DET，受不锈钢支架保护）的新现场方法，该方法基于最初为细粒沉积物和土壤开发的方法。 NO3−、NH4+ 和溶解的 Mn 的浓度梯度以厘米分辨率测量。我们观察到河床（0-30cm）中 NO3−、NH4+ 和 Mn 浓度的精细变化，这些变化仅在高分辨率下才明显，并将它们与低分辨率多级渗压计获得的 NO3− 和 NH4+ 剖面进行比较。通过 DET 测量的 NO3− 和 NH4+ 浓度范围大于通过 30 厘米深度的河床多级渗压计孔隙水采样以粗分辨率测量的浓度范围。根据结果，河床中氧化还原敏感化学物质的高分辨率剖面有助于识别和解决生物地球化学活动的热点。使用 DET 测量的 NH4+ 高于从多级采样器收集的孔隙水测量值。需要进一步研究以确定 NH4+ 测量的任一程序是否存在系统偏差。
Here we evaluate a new field methodology for the deployment of Diffusive Equilibrium in Thin Films (DET, protected in stainless steel holders) in coarse riverbed sediments based on that originally developed for fine-grained sediments and soils. Concentration gradients of NO3−, NH4+and dissolved Mn were measured at cm resolution. We observed fine scale changes in NO3−, NH4+, and Mn concentrations in the river bed (0–30cm) that were only evident at high resolution and compared them to profiles of NO3−and NH4+obtained with low resolution multilevel piezometers. The range in concentrations of NO3−and NH4+measured through DET was larger than those measured at coarse resolution through pore water sampling from multilevel piezometer in the riverbed over the 30cm depth. According to the results, high resolution profiles of redox sensitive chemical species in riverbeds could help in identifying and resolving hotspots of biogeochemical activity. Measurements of NH4+using DET were higher than measurements in pore water collected from the multilevel samplers. Further studies are needed to establish whether there is a systematic bias associated with either procedure for the measurement of NH4+.
新兴水生植物直立三棱的生物力学特性：对低能量河流中细泥沙滞留的影响
影响因子：
3.8
作者：
Liffen T
通讯作者：
Liffen T