Soil health in temperate agroforestry: influence of tree species and position in the field

ABSTRACT

Alley cropping agroforestry – whereby tree rows are integrated in crop plots – is considered as a lever for the agroecological transition. Its benefit for enhancing soil functioning is rarely studied. We studied soil health in a 25 years temperate agroforestry plot cultivated with barley (Hordeum vulgare) according to two factors: i. the position to the tree row; and ii. the tree species. Soil health was assessed in three positions (in the tree row; in the crop alley next to the tree row and at 6.5 m from the tree row), for three contrasted tree species (Acer monspessulanum, Fraxinus sp., Pyrus communis) using two integrative methods based on soil biological activity (Biofunctool®, MicroResp^TM). The position factor explained soil health differences the best: mean indexes were found 1.6 times higher in the tree row than in both positions in the crop alley, especially the structure maintenance function was impacted (indexes in the tree row = 0.21 to 0.26; indexes in the crop alley = 0.11 to 0.17). Tree species had less impact on soil health and impacted only carbon dynamics and microbial catabolic profiles. Our study invites to consider spatial organization and tree species to optimize soil ecosystem services in agroforestry systems.

KEYWORDS:

• Alley cropping
• soil health
• spatial heterogeneity
• Biofunctool®
• MicroResp^TM

Acknowledgements

This study was carried out within the framework of the Systèmes Agroforestiers et leurs Linéaires Sous-Arborés (SALSA) inter-unit research project. The study benefited from the UMR EMMAH and UMR Eco&Sols technical platforms for soil analyses. The authors would like to thank all of the technicians who helped with the study, especially Lydie Dufour and Jean-François Bourdoncle for providing access to the field and information on the study plot. Moreover, the authors would like to thank the colleagues and trainees of the UMR ABSys for their support during the field measurements, as well as Isabelle Bertrand for the scientific exchanges on the study results. Finally, we would like to thank the two anonymous reviewers and the editor who provided useful comments to improve the quality of the paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplemental data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/03650340.2022.2116013.

Notes

1. CLIMATE-DATA.ORG for Prades-le-Lez consulted in October 2021 available at https://fr.climate-data.org/europe/france/languedoc-roussillon/prades-le-lez-65221/

Additional information

Funding

This study was carried out within the framework of the Systèmes Agroforestiers et leurs Linéaires Sous-Arborés (SALSA) inter-unit research project, financed by the INRAE SALSA Project AgroEcoSystem department. The study benefited from the UMR EMMAH and UMR Eco&Sols technical platforms for soil analyses.