부산대학교 도서관

A promising tracer for partitioning the global balance of CO2 is carbonyl sulfide (COS orOCS), a trace gas with shared leaf-level mechanisms to CO2 and H2O. A number of studieshave used COS to derive insights into photosynthesis and transpiration at ecosystem to globalscales. Though it remains unclear whether COS reflects photosynthesis or stomatalconductance most strongly, as its leaf biochemical and physical processes are not perfectlyanalogous to CO2 and H2O. Recent work to characterize COS soil fluxes (e.g., microbialconsumption1 and coupled biological-abiotic emissions2) has advanced our ability to isolateleaf-level information from other ecosystem components. There is a need to evaluate themodels that encapsulate our current understanding of leaf and soil COS fluxes and predictionsof carbon and water cycling against independent constraints in tractable experimentalsystems. Here, we describe a controlled and constrained experimental mesocosm in which fluxesof COS, CO2, and H2O were measured at ecosystem and soil scales and were compared toindependent constraints on carbon and water cycling (i.e., CO2 and H2O isotopes), vegetationdynamics, and soil biological and abiotic properties. Our study system is the miniature replica(1 m2) of the large Landscape Evolution Observatory (LEO) hillslopes (330 m2)housed in the University of Arizona Biosphere 2 infrastructure and filled with 1-mdeep basaltic soil from a bare soil state to a vegetated ecosystem. I will presentthe results of our aims to determine: 1) whether soil COS fluxes are significantand related to soil physical and microbial factors, including carbonic anhydrasegene diversity, 2) how plants and plant-microbe interactions influence COS fluxes,and 3) how well ecosystem-scale COS fluxes track photosynthesis and stomatalconductance. References cited: 1L. K. Meredith, J. Ogée, K. Boye, E. Singer, L. Wingate,C. von Sperber, A. Sengupta,M. Whelan, E. Pang, M. Keiluweit,N. Brüggemann, J. A. Berry, P. V. Welander, Soilexchange rates of COS and CO18O shift with the diversity of microbial communities andtheir carbonic anhydrase enzymes, under review, The ISME Journal 2L. K. Meredith, K. Boye, C. Youngerman, M. Whelan, J. Ogée, J. Sauze, L. Wingate,Coupled biological and abiotic mechanisms driving carbonyl sulfide production insoils, Soil Systems, 2(3), 37. 2018. https://doi.org/10.3390/soilsystems2030037 [ABSTRACT FROM AUTHOR]