Identification of environmentally significant halomethanes using stable isotope techniques

虽然最近越来越明显的是，陆地生态系统在生产，消费和挥发性卤化化合物的排放中发挥着重要作用，他们仍然是非常差的特点。研究卤代甲烷生命周期的一个潜在的有力工具是使用稳定同位素比（13 C/12 C，2 H/1 H）。在全球碳循环过程中产生和破坏的化合物的碳同位素组成（δ 13 C值）的变化经常被成功地用于研究地球化学循环和全球源-汇关系以及潜在的机制。作为DFG研究单位HALOPROC的一部分，拟议的研究活动的目标是进一步探索与环境有关的卤代甲烷的形成，如氯甲烷、溴甲烷、碘甲烷、氯仿和溴仿;并利用稳定同位素方法研究其生物地球化学循环。挥发性卤代化合物的稳定同位素值将从俄罗斯南部半干旱地区收集的一系列样品中测量。将对影响卤化碳排放的若干环境参数进行实验室调查。此外，还将进行一系列复杂程度不同的实验室实验，以获得更多关于卤化碳形成的基本机制的信息。

Although it has recently become more evident that terrestrial ecosystems play an important role in production, consumption and emission of volatile halogenated compounds, they are still very poorly characterized. A potentially powerful tool in the investigation of the lifecycle of halomethanes is the use of stable isotope ratios (13C/12C, 2H/1H). Variations in the carbon isotope composition (13C values) of compounds, produced and destroyed in the global carbon cycle, are often used successfully to investigate biogeochemical cycles and global source-sink relationships, as well as the underlying mechanisms. The objective of the proposed research activities as part of the DFG research unit HALOPROC is to further explore the formation of environmentally-relevant halomethanes such as chloromethane, bromomethane, iodomethane, chloroform and bromoform; and to study their biogeochemical cycles utilising a stable isotope approach. Stable isotope values of volatile halogenated compounds will be measured from a series of samples collected in semi -arid areas of South Russia. Laboratory investigations of several environmental parameters influencing the emissions of halocarbons will be conducted. Furthermore, a series of laboratory experiments with varying degrees of complexity will be conducted to gain more information about the underlying mechanisms involved in halocarbon formation.