TECO: Carbon Monoxide Consumption by Forest and Agroecosystem Soils

9728363 King一氧化碳是比甲烷更动态的大气成分，以较低的浓度但显著较高的通量出现。CO和羟基自由基迅速相互作用，影响一些大气参数：对流层的氧化状态;甲烷、非甲烷有机物和无机物的命运和停留时间;对流层臭氧;以及热力强迫的程度。土壤消耗大气中的一氧化碳，根据来源估计，占全球碳预算的10-25%。土壤CO吸收和产生的一些控制措施已得到普遍描述，但仍有许多未知之处。农业生态系统中的CO吸收的细节是特别粗略的，尽管事实上，他们占据了约10%的陆地表面积，并有一些重要的微量气体的不成比例的影响。有限的现场结果表明，CO吸收在农业生态系统中可能相当于或大于在不受干扰的系统中的吸收。刺激农业生态系统中的CO消耗可以部分改善甲烷吸收的抑制，伴随着农业通过提高对流层OH的可用性。由于CO的吸收是高达10倍以上的甲烷吸收在全球范围内，土壤CO动态的微小变化（积极或消极）可以有一个显着的影响甲烷的命运。 这项研究将具体确定农业实践对土壤消耗大气CO的影响程度。将使用缅因州和格鲁吉亚的研究中心，在质地梯度上将农业土壤与类似的非农业土壤进行比较。这项研究将集中在气体交换，水制度，温度和各种农业干扰（施肥，农药的使用，耕作，免耕），作为控制CO通量。在何种程度上，几个微生物组的CO氧化剂不同的功能，土地利用也将被确定。这项研究的结果将建立两个速率和土壤CO动态的主要控制，以及CO吸收对气候变化和其他人为扰动的敏感性。

9728363 King Carbon monoxide is a more dynamic component of the atmosphere than methane, occurring at a lower concentration but substantially higher flux. CO and hydroxyl radical interact rapidly, affecting a number of atmospheric parameters: the oxidative state of the troposphere; the fate and residence times of methane, non-methane organics and inorganics; tropospheric ozone; and the extent of thermal forcing. Soils consume atmospheric CO, accounting for 10-25% of the global carbon budget, depending on the source estimate. Some of the controls of soil CO uptake and production have been described generally, but much remains unknown. Details of CO uptake in agroecosystems are particularly sketchy, in spite of the fact that they occupy about 10% of terrestrial surface area, and have a disproportionate impact on a number of important trace gases. Limited field results have suggested that CO uptake in agroecosystems may be equivalent to or greater than uptake in undisturbed systems. Stimulation of CO consumption in agroecosystems could partially ameliorate the inhibition of methane uptake that accompanies agriculture by enhancing the availability of tropospheric OH. Since CO uptake is as much as 10-fold greater than methane uptake on a global basis, small changes in soil CO dynamics (positive or negative) can have a significant impact on the fate of methane. This study will determine specifically the extent to which agricultural practices affect atmospheric CO consumption by soils. Agricultural soils will be compared with similar non-agricultural soils across a gradient of texture using sites in Maine and Georgia. This study will focus on gas exchange, water regimes, temperature, and various agricultural disturbances (fertilization, pesticide use, tilling, no-till), as controls of CO fluxes. The extent to which several microbial groups of CO oxidizers vary as a function of land use will also be determined. The results of this study will establish both rates and the major controls of soil CO dyn amics, as well as the sensitivity of CO uptake to climate change and other anthropogenic perturbations.