Atmo-ecometabolomics: a novel atmospheric particle chemical characterization methodology for ecological research

Albert Rivas-Ubach1, Yina Liu2,1, Allison L. Steiner3, Jordi Sardans4,5, Malak M. Tfaily1, Gourihar Kulkarni6, Young-Mo Kim7, Eric Bourrianne8, Ljiljana Paša-Tolić1, Josep Peñuelas5,4, Alex Guenther9
1Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, USA
2Geochemical and Environmental Research Group, Texas A&M University, College Station, USA
3Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, USA
4Global Ecology Unit CREAF-CSIC, Cerdanyola del Vallès, Spain
5CREAF, Cerdanyola Del Vallès, Spain
6Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, USA
7Biological Sciences Division, Pacific Northwest National Laboratory, Richland, USA
8Faculté des Sicences et d’Ingénierie, Université de Toulouse III Paul Sabatier, Toulouse, France
9Department of Earth System Science, University of California (Irvine), Irvine, USA

Tóm tắt

Aerosol particles play important roles in processes controlling the composition of the atmosphere and function of ecosystems. A better understanding of the composition of aerosol particles is beginning to be recognized as critical for ecological research to further comprehend the link between aerosols and ecosystems. While chemical characterization of aerosols has been practiced in the atmospheric science community, detailed methodology tailored to the needs of ecological research does not exist yet. In this study, we describe an efficient methodology (atmo-ecometabolomics), in step-by-step details, from the sampling to the data analyses, to characterize the chemical composition of aerosol particles, namely atmo-metabolome. This method employs mass spectrometry platforms such as liquid and gas chromatography mass spectrometries (MS) and Fourier transform ion cyclotron resonance MS (FT-ICR-MS). For methodology evaluation, we analyzed aerosol particles collected during two different seasons (spring and summer) in a low-biological-activity ecosystem. Additionally, to further validate our methodology, we analyzed aerosol particles collected in a more biologically active ecosystem during the pollination peaks of three different representative tree species. Our statistical results showed that our sampling and extraction methods are suitable for characterizing the atmo-ecometabolomes in these two distinct ecosystems with any of the analytical platforms. Datasets obtained from each mass spectrometry instrument showed overall significant differences of the atmo-ecometabolomes between spring and summer as well as between the three pollination peak periods. Furthermore, we have identified several metabolites that can be attributed to pollen and other plant-related aerosol particles. We additionally provide a basic guide of the potential use ecometabolomic techniques on different mass spectrometry platforms to accurately analyze the atmo-ecometabolomes for ecological studies. Our method represents an advanced novel approach for future studies in the impact of aerosol particle chemical compositions on ecosystem structure and function and biogeochemistry.

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