干旱区生态环境知识资源中心(Arid): Processes driving soil CO2 temporal variability in Antarctic Dry Valleys

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DOI	10.1016/j.geoderma.2018.09.050
	Processes driving soil CO2 temporal variability in Antarctic Dry Valleys
	MacIntyre, Christopher 1; Risk, David 1; Lee, Charles K.2; Cary, S. Craig 2
通讯作者	MacIntyre, Christopher ; Risk, David
来源期刊	GEODERMA
ISSN	0016-7061
EISSN	1872-6259
出版年	2019
卷号	337 页码:871-879
英文摘要	The polar deserts of the McMurdo Dry Valleys, Victoria Land, Antarctica, are among the most hostile places on Earth, where terrestrial biota is limited to small patches of hospitable land. Carbon dioxide (CO2) soil surface flux has been used to estimate the rates of biological activity in hospitable areas, but researchers have also observed CO2 fluctuations at sites with low biological activity, including strong negative fluxes suggestive of an abiotic sink for CO2. To better characterize the biotic and abiotic controls on soil surface CO2 flux, and their relative contributions to variability, we designed and executed a long-term monitoring experiment in four of the McMurdo Dry Valleys. This experiment used automated temporal monitoring of both CO2 efflux, and soil concentrations, at sub-diel timescales. In general, the fluxes we observed were well under < 0.1 mu mol m(-2) s(-1), which is consistent with other studies in upland Dry Valley soils. Aside from one short-term biological event in which consistent fluxes to atmosphere were observed over a period of some days, time series monitoring showed that soils generally released CO2 during the day, and behaved as a CO2 sink at night - in roughly equal proportion, where the sum of fluxes over each diel period were near zero. This pattern was observed across different sites and valleys, was very repeatable, and was highly coupled with soil temperature. These patterns were well explained by solubility cycling of CO2 into and out of alkaline waters in the soil profile. A laboratory soil simulation experiment confirmed that solubility cycling could generate the magnitude (tens of ppm) of soil CO2 concentration changes observed in these alkaline soils. This study has consequences for measuring biotic activity and Antarctic greening because abiotic and biotic drivers of CO2 can co-exist. Novel tracer techniques (isotopic or other accessory gases) must be developed to better quantify biotic activity and change in these unique McMurdo Dry Valleys environments.
英文关键词	Antarctica CO2 flux Dry Valley Soil respiration Geochemistry Solubility cycling
类型	Article
语种	英语
国家	Canada ; New Zealand
收录类别	SCI-E
WOS记录号	WOS:000456761500086
WOS关键词	CARBON-DIOXIDE ; ORGANIC-CARBON ; FLUX
WOS类目	Soil Science
WOS研究方向	Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/215921
作者单位	1.St Francis Xavier Univ, Dept Earth Sci, Antigonish, NS B2G 2W5, Canada; 2.Univ Waikato, Int Ctr Terr Antarctic Res, Hamilton, New Zealand
推荐引用方式 GB/T 7714	MacIntyre, Christopher,Risk, David,Lee, Charles K.,et al. Processes driving soil CO2 temporal variability in Antarctic Dry Valleys[J],2019,337:871-879.
APA	MacIntyre, Christopher,Risk, David,Lee, Charles K.,&Cary, S. Craig.(2019).Processes driving soil CO2 temporal variability in Antarctic Dry Valleys.GEODERMA,337,871-879.
MLA	MacIntyre, Christopher,et al."Processes driving soil CO2 temporal variability in Antarctic Dry Valleys".GEODERMA 337(2019):871-879.