@article{fdi:010085343,
  title = {{M}echanisms and kinetics of (de-)protection of soil organic carbon in earthworm casts in a tropical environment},
  author = {{P}uche, {N}icolas and {R}umpel, {C}. and {L}e {M}er, {G}. and {J}ouquet, {P}ascal and {M}azurier, {A}. and {C}aner, {L}. and {G}arnier, {P}. and {T}ran, {T}. {M}. and {B}ottinelli, {N}icolas},
  editor = {},
  language = {{ENG}},
  abstract = {{E}arthworms have potential to stabilize soil organic carbon ({SOC}), but the biophysical controls on {SOC} dynamics in earthworm casts and the {SOC} residence time in casts is poorly known. {T}o this end, we aimed to investigate (1) the kinetics of {SOC} (de-) protection in earthworm casts deposited in a tropical environment and (2) changes in the spatial relationships between fresh particulate organic matter ({POM}) and pore architecture within casts. {O}ur experimental approach was to espose casts produced by the anecic earthworm {A}mynthas adexilis to tropical temperature and rainfall by placing them in a woodland in northern {V}ietnam. {F}or 400 d, we monitored the dynamics of cast microstructures using {X}-ray micro-computed tomography and compared them to those of the surrounding soil aggregates (control). {W}e also measured potential {CO}2 emissions of the same samples in a laboratory incubation. {A}s expected, recently egested casts had higher {SOC} (1.9-fold) and {POM} volumes (7-fold) than aggregates, whereas their total imaged porosity was 4 times less. {T}he {SOC} of casts was more labile than {SOC} of aggregates, as casts had 3 times more potentially mineralizable {SOC}. {B}y 72 d of exposure to field conditions, the casts and aggregates had similar potential {SOC} mineralization, indicating that they had developed a similar level of {SOC} protection. {T}emporal changes in {SOC} mineralization rates were related to variations in {POM} volume, particularly those connected to the outside of the cast. {A}fter 400 d of exposure, casts had still greater {POM} volumes (2.5-fold) and higher {SOC} contents (1.6-fold) but similar total imaged porosity and {SOC} stability as aggregates. {I}n conclusion, these results clearly indicated the direct involvement of earthworms in {SOC} stabilization through their impact on {POM} and pore spatial arrangements, which may have led to prolonged {SOC} sequestration for > 400 d.},
  keywords = {{ZONE} {TROPICALE} ; {B}ioturbation ; {P}hysical protection ; {M}acrofauna},
  booktitle = {},
  journal = {{S}oil {B}iology and {B}iochemistry},
  volume = {170},
  numero = {},
  pages = {108686 [11 ]},
  ISSN = {0038-0717},
  year = {2022},
  DOI = {10.1016/j.soilbio.2022.108686},
  URL = {https://www.documentation.ird.fr/hor/fdi:010085343},
}