The cycling of greenhouse gases (GHGs) in soils is fundamentally regulated by molecular oxygen, and trees restructure the local O₂ landscape through root macropore networks, rhizosphere oxygen demand, and canopy-mediated moisture redistribution, generating spatially structured redox transitions that govern CO₂, N₂O, and CH₄ fluxes across distances of just a few meters from the stem. Despite this inherent spatial heterogeneity, most studies measuring soil GHG emissions in tree-based systems report fluxes from single locations without documenting distance from trees, effectively assuming spatial homogeneity where none exists. We introduce triproximity, a conceptual framework that considers tree–soil GHG interactions across three spatial dimensions: (i) horizontal distance from tree stems, (ii) vertical soil profile depth, and (iii) structural position relative to tree components, including the stem itself as a gas conduit. Following PRISMA guidelines, we systematically reviewed 107 field-based studies published between 2010 and 2025 spanning shelterbelts, agroforestry, orchards, silvopastoral systems, and riparian buffers across temperate, subtropical, and arid climates. Only 37.4% of studies explicitly reported measurement distance from trees, a proportion that has not improved despite a near four-fold increase in publication volume since 2020. Methane uptake showed the most consistent spatial response, with higher oxidation rates in the near-tree zone across diverse system types, most plausibly reflecting root-mediated improvements in soil aeration and methanotrophic activity. Nitrous oxide responses were context-dependent, governed by competing substrate availability and moisture controls that the triproximity dimensions help disentangle. Carbon dioxide fluxes showed no universal spatial pattern, yet were responsive to specific proximity dimensions once the dominant source term was identified. Stem-level gas transport was virtually unmeasured across the dataset, likely biasing ecosystem GHG budgets toward underestimation. We propose a minimum triproximity-based sampling protocol specifying horizontal distances, vertical depths, structural positions, and replicate requirements for five major tree-based system types, and call for journals to adopt spatial reporting as a minimum submission standard for GHG studies in tree-based agricultural systems.

En pecán, el área de proyección de copa (APC), el diámetro de tronco (DBH) y la altura del árbol (H) son componentes de la arquitectura arbórea que interactúan entre sí y con el suelo. El objetivo de este trabajo fue validar si las relaciones funcionales de la arquitectura arbórea a nivel intraárbol y su interrelación con los recursos edáficos (carbono orgánico del suelo [COS] y zinc [Zn]) observadas en otras plantaciones frutales ocurren también en una plantación de pecán bajo las condiciones edafoclimáticas específicas del sudeste de la provincia de Buenos Aires, Argentina. Para ello se determinaron: el APC mediante fotogrametría utilizando un dron mini, COS, nitratos, amonio y Zn en suelo (0-20 cm de profundidad) e indicadores dasométricos (DBH, altura), medidos con cinta métrica y regla telescópica. Las determinaciones se realizaron durante el mes de abril (coincidiendo con el momento del fin del llenado de la nuez) durante los años 2022, 2023 y 2024 en una plantación multicultivar ubicada en la EEA INTA Balcarce (37,76º S, 58,29º O). Se encontraron correlaciones positivas para APC vs. DBH, DBH vs. H, y APC vs. H (en todos los casos, p<0,001), APC vs. COS (r=0,63, p=0,001) (2022, 2023 y 2024), y para la concentración de Zn vs. APC (r=0,54, p=0,03) (2022 y 2023). Nuestros resultados indican que los parámetros medidos intraplanta (APC, DBH y H) se retroalimentan positivamente, pero la variable más asociada a los recursos disponibles que se encuentren en el suelo es el APC.

We introduce triproximity, a conceptual framework that organizes tree–soil greenhouse gas (GHG) interactions across three spatial dimensions: (i) horizontal distance from tree stems, (ii) vertical soil profile depth, and (iii) structural position relative to tree components including the stem itself as a gas conduit. This addresses a critical and previously unquantified methodological gap in the literature. Despite the inherent spatial heterogeneity of tree-based agricultural systems, where molecular oxygen gradients structured by root macropore networks, rhizosphere demand, and canopy-mediated moisture redistribution govern CO₂, N₂O, and CH₄ fluxes across distances of just a few meters from the stem, most studies report GHG emissions from single locations without documenting distance from trees, effectively assuming spatial homogeneity where none exists. Following PRISMA guidelines, we systematically reviewed 107 field-based studies identified through a Scopus search (December 2025) of tree-based systems published between 2010 and 2025. Only 37.4% of studies explicitly reported measurement distance from trees, a proportion that has not improved despite a nearly four-fold increase in publication volume since 2020. Through narrative synthesis, we show that CH₄ uptake follows the most consistent spatial response, with higher oxidation rates in the near-tree zone across diverse system types; N₂O responses are context-dependent and governed by competing substrate availability and moisture controls; and CO₂ fluxes show no universal spatial pattern yet respond predictably to specific proximity dimensions once the dominant source term is identified. Stem-level gas transport remains virtually unmeasured across the dataset, likely biasing ecosystem GHG budgets systematically. We propose a minimum triproximity-based sampling protocol for five major tree-based system types and call for journals to adopt spatial reporting as a minimum submission standard. This review was not pre-registered and received no external funding.