Aarhus University Centre for Water Technology, Department of Biology, Section for Microbiology, Ny Munkegade 114, 8000 Aarhus C, Denmark; Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Stremayrgasse 9/II, 8010 Graz, Austria.
Aarhus University Centre for Water Technology, Department of Biology, Section for Microbiology, Ny Munkegade 114, 8000 Aarhus C, Denmark.
Environ Int. 2020 Nov;144:106080. doi: 10.1016/j.envint.2020.106080. Epub 2020 Sep 2.
The application of fertilizers and manure on fields is the largest source of ammonia (NH) in the atmosphere.·NH emission from agriculture has negative environmental consequences and is largely controlled by the chemical microenvironment and the respective biological activity of the soil. While gas phase and bulk measurements can describe the emission on a large scale, those measurements fail to unravel the local processes and spatial heterogeneity at the soil air interface. We report a two dimensional (2D) imaging approach capable of visualizing three of the most important chemical parameters associated with NH emission from soil. Besides the released NH itself also O and pH microenvironments are imaged using reversible optodes in real-time with a spatial resolution of <100 µm. This combined optode approach utilizes a specifically developed NH optode with a limit of detection of 2.11 ppm and a large working range (0-1800 ppm) ideally suited for studying NH volatilization from soil. This NH optode will contribute to a better understanding of the driving factors for NH emission on a microscale and has the potential to become a valuable tool in studying NH dynamics.
农田施肥和施用有机肥是大气中氨（NH）的最大来源。农业氨排放对环境有负面影响，主要受土壤化学微环境和各自的生物活性控制。虽然气相和体相测量可以大规模描述排放，但这些测量无法揭示土壤空气界面处的局部过程和空间异质性。我们报告了一种二维（2D）成像方法，能够可视化与土壤中 NH 排放相关的三个最重要的化学参数。除了释放的 NH 本身，还使用可逆光学传感器实时成像 O 和 pH 微环境，空间分辨率<100 µm。这种组合光学传感器方法利用了一种专门开发的 NH 光学传感器，其检测限为 2.11 ppm，工作范围大（0-1800 ppm），非常适合研究土壤中 NH 的挥发。这种 NH 光学传感器将有助于更好地了解微尺度上 NH 排放的驱动因素，并有可能成为研究 NH 动力学的有用工具。
