Open Access4D Surface Reconstructions to Study Microscale Structures and Functions in Soil Biogeochemistry
Author(s) -
Alexander Øst,
Tianyi Wu,
Carmen Höschen,
Carsten W. Mueller,
Tom Wirtz,
JeanNicolas Audinot
Publication year - 2021
Publication title -
environmental science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.851
H-Index - 397
eISSN - 1520-5851
pISSN - 0013-936X
DOI - 10.1021/acs.est.1c02971
Subject(s) - microscale chemistry , biogeochemical cycle , biogeochemistry , secondary ion mass spectrometry , nanoscopic scale , organic matter , chemical imaging , carbon fibers , chemistry , mineralogy , nanotechnology , ion , geology , materials science , hyperspectral imaging , environmental chemistry , remote sensing , composite material , mathematics , organic chemistry , composite number , mathematics education
The development of high-resolution microscopy and spectroscopy techniques has allowed the analysis of microscopic 3D objects in fields like nanotechnology and life and soil sciences. Soils have the ability to incorporate and store large amounts of organic carbon. To study this organic matter (OM) sequestration, it is essential to analyze its association with soil minerals at the relevant microaggregate scale. This has been previously studied in 2D. However, 3D surface representations would allow a variable angle and magnification analysis, providing detailed insight on their architecture. Here we illustrate a 4D surface reconstruction workflow able to locate preferential sites for OM deposition with respect to microaggregate topography. We used Helium Ion Microscopy to acquire overlapping Secondary Electron (SE) images to reconstruct the soil topography in 3D. Then we used nanoscale Secondary Ion Mass Spectrometry imaging to chemically differentiate between the OM and mineral constituents forming the microaggregates. This image was projected onto the 3D SE model to create a 4D surface reconstruction. Our results show that organo-mineral associations mainly form at medium curvatures while flat and highly curved surfaces are avoided. This method presents an important step forward to survey the 3D physical structure and chemical composition of microscale biogeochemical systems correlatively.