Advancing Carbonyl Sulfide (OCS) as an Independent Atmospheric Ttracer for Global Photosynthesis through Quantification of Microbial-mediated Sources and Sinks in Soils

这一合作项目旨在通过使用羰基硫化物(OCS)作为示踪剂，增加对植物如何影响大气碳循环的理解。OCS已显示出帮助估计植物吸收的碳量的潜力，然而，由于OCS也被土壤中的微生物消耗这一事实，其使用受到限制。拟议工作的目标是量化和预测这一OCS汇，并将所获得的知识推广到区域范围，以便更好地限制植物和土壤在总体碳收支中的作用。该项目旨在缩小目前对OCS土壤微生物吸收机制的了解差距。土壤微生物基因组学数据将与OCS通量的直接测量联系起来，从而建立一个框架，以改进对OCS从单个微生物分离物到群落并进一步到区域生态系统的吸收的量化和预测。多学科方法涉及(I)在测量OCS摄取的同时培养实验室真菌，(Ii)在阿拉斯加进行田间采样，(Iii)从碳水解酶(CA，OCS特异性摄取酶)获得和处理真菌基因组数据，以及(Iv)建立基于CA基因组学的参数化OCS摄取的迭代特征模型。这项工作的结果可能被其他具有潜在影响的小组用于更大规模的植物和土壤对碳循环影响的模型。一名研究生和一名博士后研究人员将开展实验室和实地工作，该小组将开发教育和宣传材料，纳入生物圈2号，目前生物圈2号没有关于高纬度生态系统的巡回展览。该提议由大气化学和生态系统科学计划共同资助。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This collaborative project seeks to increase understanding of how plants impact the atmospheric carbon cycle by using carbonyl sulfide (OCS) as a tracer. OCS has shown potential to help estimate the amount of carbon taken up by plants, yet, its use has been limited by the fact that OCS also is consumed by microbes in the soil. The objective of the proposed work is to quantify and predict this OCS sink and to extend acquired knowledge to regional scales so that the role of plants and soils on the overall carbon budget is better constrained. The project aims at closing the gap of current understanding of soil microbial uptake mechanisms of OCS. Soil microbial genomics data will be linked to direct measurements of OCS fluxes, thereby building a framework to improve quantification and prediction of OCS uptake from individual microbial isolates to communities and further to regional ecosystems. The multi-disciplinary approach involves (i) growing laboratory fungal cultivations while measuring OCS uptake, (ii) field sampling in Alaska, (iii) obtaining and processing fungal genome data from the enzyme carbonic anhydrase (CA, the OCS specific uptake enzyme), and (iv) building iterative trait models that parametrize OCS uptake based on CA genomics. The outcome of this work may be used by other groups with potential impact in larger scale models of plant and soil impacts on the carbon cycle. One graduate student and one postdoctoral researcher will carry out the laboratory and field work, and the team will develop education and outreach materials to be integrated into Biosphere 2, where currently a tour exhibit on high latitude ecosystems is absent. The proposal is co-funded by the Atmospheric Chemistry and Ecosystems Science Programs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.