干旱区生态环境知识资源中心(Arid): Solar Photochemical Emission of CO(2)From Leaf Litter: Sources and Significance to C Loss

Arid

DOI	10.1007/s10021-019-00473-8
	Solar Photochemical Emission of CO(2)From Leaf Litter: Sources and Significance to C Loss
	Day, Thomas A.; Bliss, Michael S.
通讯作者	Day, TA (corresponding author), Arizona State Univ, Sch Life Sci, Tempe, AZ 85281 USA.
来源期刊	ECOSYSTEMS
ISSN	1432-9840
EISSN	1435-0629
出版年	2020
卷号	23 期号:7 页码:1344-1361
英文摘要	Although photodegradation can be a significant mechanism of plant litter decay in drylands, the abiotic photochemical emission component of this process is not well characterized. We measured the temperature response of abiotic photochemical emission of CO(2)from 12 litter types under midday sunlight in the Sonoran Desert, assessed what litter traits predicted emission rates, and estimated its significance to litter C loss. Emission rates increased exponentially with temperature (Q(10)= 1.75) and declined as litter decayed. Rates varied substantially among litter types. Microbial respiration rates of litter explained the most variation in emission rates at lower temperature (78% at 45 degrees C), suggesting that compounds amenable to microbial consumption were major precursors of emission. In contrast, wax concentrations explained the most variation at high temperature (76% at 70 degrees C), implying that precursors shifted with temperature. Photochemical emission of initial litter at 55 degrees C was a strong predictor of the mass loss of litter in full sunlight over 34 months in the field, explaining 67% of the variation among litter types. We estimate that photochemical emission of CO(2)was responsible for 10% of all C lost from litter in sunlight over 34 months and accounted for 39% of the greater C lost from litter in sunlight compared to litter that did not receive sunlight in the UV to blue wavelength bands. Hence, abiotic photodegradation via photochemical emission appeared to be a significant pathway for C loss from sunlit litter. The substantial exponential increase in photochemical emission with temperature illustrates that temperature needs to be considered in assessments of abiotic photodegradation and implies this process will be greatest in systems where litter is exposed to high solar irradiance in conjunction with high temperatures.
英文关键词	Carbon dioxide Decay Drylands Litter decomposition Photochemical emission Photodegradation Solar radiation Sonoran Desert UV radiation Waxes
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000575578000001
WOS关键词	PLANT LITTER ; ULTRAVIOLET-RADIATION ; UV-RADIATION ; SEMIARID ECOSYSTEMS ; METHANE EMISSIONS ; DECOMPOSITION ; PHOTODEGRADATION ; CARBON ; LIGNIN ; TEMPERATURE
WOS类目	Ecology
WOS研究方向	Environmental Sciences & Ecology
来源机构	Arizona State University
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/369260
作者单位	[Day, Thomas A.; Bliss, Michael S.] Arizona State Univ, Sch Life Sci, Tempe, AZ 85281 USA
推荐引用方式 GB/T 7714	Day, Thomas A.,Bliss, Michael S.. Solar Photochemical Emission of CO(2)From Leaf Litter: Sources and Significance to C Loss[J]. Arizona State University,2020,23(7):1344-1361.
APA	Day, Thomas A.,&Bliss, Michael S..(2020).Solar Photochemical Emission of CO(2)From Leaf Litter: Sources and Significance to C Loss.ECOSYSTEMS,23(7),1344-1361.
MLA	Day, Thomas A.,et al."Solar Photochemical Emission of CO(2)From Leaf Litter: Sources and Significance to C Loss".ECOSYSTEMS 23.7(2020):1344-1361.