Collaborative Research: Characterization of the Wetlands Source of Tropospheric Methyl Bromide (CH3Br) and Methyl Chloride (CH3Cl)

这个项目是新汉普郡大学和阿拉斯加大学的合作项目。它被提交给环境地球化学和生物地球化学方案(EGB)，并得到大气科学司的大气化学方案、地球科学司的岩石学和地球化学方案以及水文科学方案的支持，以及数学和物理科学局的多学科活动办公室和化学司的支持。甲基溴和甲基氯是受人类活动影响的痕量气体，在平流层臭氧平衡中起着重要作用。尽管它们的生物地球化学机制还不是很清楚，但众所周知，这些气体有重要的自然来源。这些气体的大气收支失衡，因为已确定的这两种气体的汇超过了已知的来源。最近，人们发现被洪水淹没的泥炭地是这些气体的陆地来源，这可能会影响它们的全球收支。关于这种新污染源的区域分布和大小，以及洪水淹没的土壤可能如何影响其周围混合比，信息仍然匮乏。在这个项目中，将在各种泥炭地直接测量甲基溴和甲基氯的通量，并进行实验，以确定控制这些通量的化学、物理和生物参数。

This project is a collaboration between the University of New Hampshire and the University of Alaska. It was submitted to the Environmental Geochemistry and Biogeochemistry Program (EGB) and is supported by the Atmospheric Chemistry Program of the Division of Atmospheric Sciences; the Petrology and Geochemistry Program, and the Hydrologic Sciences Program of the Division of Earth Sciences; and the Office of Multidisciplinary Activities and the Division of Chemistry of the Directorate for Mathematical and Physical Sciences. Methyl bromide and methyl chloride are anthropogenically influenced trace gases that play an important role in the stratospheric ozone balance. Although their biogeochemisty is not well understood, it is known that these gases have significant natural sources. The atmospheric budgets of these gases are out of balance because the identified sinks for both gases outweigh known sources. Recently, it has been discovered that flooded peatlands are a terrestrial source for these gases which could impact their global budget. Information is still lacking about the regional distribution and magnitude of this new source and how the flooded soils might affect their ambient mixing ratios. In this project direct flux measurements of methyl bromide and methyl chloride will be made in a variety of peatlands and experiments will be carried out to determine the chemical, physical, and biological parameters controlling these fluxes.