@article{fdi:010068060,
  title = {{D}ynamics of soil organic matter based on new {R}ock-{E}val indices},
  author = {{S}ebag, {D}avid and {V}errecchia, {E}.{P}. and {C}{\'e}cillon, {L}. and {A}datte, {T}. and {A}lbrecht, {R}. and {A}ubert, {M}. and {B}ureau, {F}. and {C}ailleau, {G}. and {C}opard, {Y}. and {D}ecaens, {T}. and {D}isnar, {J}.{R}. and {H}et{\'e}nyi, {M}. and {N}yilas, {T}. and {T}rombino, {L}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his paper aims to develop a new approach to interpret soil organic matter ({SOM}) dynamics from {R}ock-{E}val pyrolysis. {R}ock-{E}val standard parameters ({T}p{S}2, {HI}, {OI}) are limited when applied to {SOM}, as they were defined for tracking the origin of sedimentary organic matter (i.e. terrestrial vs aquatic and lacustrine vs marine). {T}his study proposes new {R}ock {E}val based indices, projected on a new diagram plotting > 1300 samples, including litter and soil horizons, pure compounds and organic material. {T}hese new parameters reflect the thermal stability of {SOM} rather than its bulk chemistry. {T}heir calculations are based on the contribution of four different areas ({A}1 to {A}4) integrated below the {S}2 pyrogram (amounts of released hydrocarbon compounds during the pyrolysis step). {R}esults demonstrate that the relative values of {A}1 to {A}4 parameters can be used to survey the evolution of {SOM} during pedogenesis. {T}hese {R}ock-{E}val parameters revealed a consistent thermal differentiation of {SOM} with depth, from thermally labile biogenic {SOM} in soil organic horizons to thermally stable mineral-associated {SOM} compounds in organo-mineral and mineral soil horizons, indicating a pedogenetic stabilization of {SOM}. {F}inally, newly defined {I}- and {R}-indices integrate the respective parts of {A}1 to {A}4 parameters into {SOM} dynamics, the {I}-index emphasizing the degree of transformation of the immature organic fraction (related to {SOM} stabilization), the {R}-index highlighting the contribution of the most refractory fraction or persistent {SOM} (related to pedogenic and inherited contributions). {A}nalyses of a wide range of soils and reference samples (cellulose, lignin, humic substances, lignite, charcoal, coal, etc.) allow end-members as well as particular trends (humic, spodic, inherited) to be drawn. {S}pecific examples are provided in order to illustrate some applications and uses for this new {R}ock-{E}val based {I}/{R} diagram, from the study of grain size fractions to the evolution of {SOM} in soil chronosequences.},
  keywords = {{FRANCE} ; {HONGRIE} ; {ESPAGNE} ; {ITALIE} ; {TUNISIE} ; {NIGER} ; {BURKINA} {FASO} ; {COTE} {D}'{IVOIRE} ; {CAMEROUN} ; {GABON} ; {CONGO} ; {BOLIVIE}},
  booktitle = {},
  journal = {{G}eoderma},
  volume = {284},
  numero = {},
  pages = {185--203},
  ISSN = {0016-7061},
  year = {2016},
  DOI = {10.1016/j.geoderma.2016.08.025},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068060},
}