@article{fdi:010096387,
  title = {{S}ubsoil rhizosphere carbon enrichment and depletion : processes and scaling in tree-based systems},
  author = {{P}iton, {G}. and {T}aschen, {E}. and {D}ucrocq, {C}. and {M}artin-{B}langy, {S}. and {A}menc, {L}. and {C}astel, {P}. and {D}ezette, {D}. and {D}ugu{\'e}, {R}{\'e}mi and {F}orest, {M}. and {H}insinger, {P}. and {M}arie, {B}. and {P}ersonne, {A}. and {S}eignon, {M}. and {N}gao, {J}. and {J}ourdan, {C}. and {B}ertrand, {I}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}ree roots have the potential to release carbon into deep soil layers, where this carbon is generally considered to exhibit greater stability. {H}owever, field studies that investigate the drivers of the soil organic carbon ({SOC}) balance in the rhizosphere of trees across soil depths and that upscale this balance to the whole soil profile are lacking. {T}his study presents an innovative approach integrating normalized rhizosphere sampling and root density mapping to a depth of 1.5 m under trees from {M}editerranean agroforestry and a tree plantation. {T}he estimated {SOC} balance in the rhizosphere of the {R}obinia pseudoacacia trees varied from-38 kg {C} ha-1 to +53 kg {C} ha-1 at the different soil horizons, with a neutral balance at 0-0.3 m, a negative balance at 0.3-0.5 m and a positive balance at 0.5-1.0 m and 1.0-1.5 m of soil depth. {W}hen scaled up to the whole profile, the value was +50.6 kg {C} ha-1 for the tree plantation and +72.4 kg {C} ha-1 for the tree row for the agroforestry system, with no significant difference between these two estimates. {T}he balance between hydrolytic and oxidative enzyme activities and between fungal guilds indicated increasing nutritional constraints for microbial saprotrophs at depth. {I}n the subsoil, these nutritional constraints were locally attenuated in the rhizosphere, inducing a substantial increase in microbial abundance and triggering a pronounced shift from oligotrophic to copiotrophic communities, which in turn supported {SOC} enrichment. {I}n the topsoil, the lower chemical complexity of substrates available to microorganisms increases susceptibility to saprotrophic activity, which likely underlies the observed neutral or negative {SOC} balances in the rhizosphere. {T}his field study presents a scalable approach for quantifying the rhizosphere {SOC} balance in deep soil horizons and disentangling its biogeochemical drivers.},
  keywords = {{A}groforestry ; {D}eep soil horizons ; {D}eep-rooted plants ; {M}icrobial ; hotspots ; {F}ungal guilds ; {E}nzyme activities ; {FRANCE} ; {ZONE} {MEDITERRANEENNE}},
  booktitle = {},
  journal = {{S}oil {B}iology & {B}iochemistry},
  volume = {216},
  numero = {},
  pages = {110103 [14 ]},
  ISSN = {0038-0717},
  year = {2026},
  DOI = {10.1016/j.soilbio.2026.110103},
  URL = {https://www.documentation.ird.fr/hor/fdi:010096387},
}