Carbon Monoxide Photoproduction: Implications for Photoreactivity of Arctic Permafrost-Derived Soil Dissolved Organic Matter
Carbon Monoxide Photoproduction: Implications for Photoreactivity of Arctic Permafrost-Derived Soil Dissolved Organic Matter
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DOI：
10.1021/es502057n
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发表时间：
2014-08-19
影响因子：
11.4
通讯作者：
Song, Guisheng
中科院分区：
文献类型：
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作者：
Hong, Jun;Xie, Huixiang;Song, Guisheng
测定了育空地区和阿拉斯加沿岸多年冻土区土壤溶解性有机质（SDOM）的一氧化碳（CO）光生量子产率（AQY（CO）），研究了AQY（CO）与温度、离子强度、pH和SDOM浓度的关系。来自不同位置和土壤深度的SDOM都表现出相似的AQY（CO）光谱，无论土壤年龄。AQY（CO）在20 ℃升温时增加68%，从离子强度0到0.7 mol L-1时减少25%，从pH 4到8时减少25-38%。这些影响结合在一起，可以减少AQY（CO）高达72%，当SDOM从陆地的海洋条件下，在夏季在北极过境。米氏动力学的特点是在很低的底物半饱和浓度的影响SDOM稀释AQY（CO）。广义的全球尺度的关系AQY（CO）和盐度和吸光度证明，基于CO的光反应性的古permaforst SDOM是现代河流DOM和物理化学的影响帐户的向海下降的AQY（CO）在不同的河口和沿海水体中观察到。仅在这里揭示的变量就可以
Apparent quantum yields of carbon monoxide (CO) photo-production (AQY(CO)) for permafrost-derived soil dissolved organic matter (SDOM) from the Yukon River Basin and Alaska coast were determined to examine the dependences of AQY(CO) on temperature, ionic strength, pH, and SDOM concentration. SDOM from different locations and soil depths all exhibited similar AQY(CO) spectra irrespective of soil age. AQY(CO) increased by 68% for a 20 degrees C warming, decreased by 25% from ionic strength 0 to 0.7 mol L-1, and dropped by 25-38% from pH 4 to 8. These effects combined together could reduce AQY(CO) by up to 72% when SDOM transits from terrestrial environemnts to open-ocean conditions during summer in the Arctic. A Michaelis-Menten kinetics characterized the influence of SDOM dilution on AQY(CO) with a very low substrate half-saturation concentration. Generalized global-scale relationships between AQY(CO) and salinity and absorbance demostrate that the CO-based photoreactivity of ancient permaforst SDOM is comparable to that of modern riverine DOM and that the effects of the physicochemical account for the seaward decline of AQY(CO) observed in diverse estuarine and coastal water bodies. variables revealed here alone could