@article{fdi:010095902,
  title = {{P}lant-wax n-alkanes from the central {C}ongo {B}asin as palaeo-environmental and -climatic proxies},
  author = {{G}uardiola, {M}. and {B}ouka, {G}. {U}. {D}. and {A}baye, {C}. and {M}enges, {J}. and {R}ostek, {F}. and {L}educ, {G}. and {B}ard, {E}. and {S}chefuss, {E}. and {G}arcin, {Y}annick},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he central {C}ongo {B}asin is home to the world's largest tropical peatland complex and is covered with swamp forest. {I}n the face of climate change and future human activities in the region, it is important to understand the factors that determine the nature and dynamics of the peatland vegetation cover. {O}ne way to gain insight into these factors is to reconstruct the history of the central {C}ongo {B}asin peatlands. {A}nalysing lipid biomarkers extracted from peat cores such as plant wax n-alkanes enables past environmental and climatic conditions to be reconstructed. {H}owever, there is currently no information on how the production of plant waxes by different plant species influences the abundance and isotopic composition of n-alkanes in peat and other archives in the {C}ongo {B}asin. {I}n this study we analysed plant wax n-alkane abundances, delta {C}-13 and delta {D} values according to photosynthetic pathways ({C}-3 vs. {C}-4), angiosperm subclasses (dicotyledons vs. monocotyledons), and source water delta {D} values in the dominant plant types (trees, shrubs, and herbs) in the peatland area of the {C}uvette {D}epartment in the {R}epublic of the {C}ongo. {O}ur dataset enables the definition of a new n-alkane distribution index, named {GRIND}, that distinguishes between {C}-3 (mostly dicotyledons) and {C}-4 (monocotyledons) plants as follows: (n-{C}-27 + n-{C}-33 + n-{C}-35)/(n-{C}-25 + n-{C}-27 + n-{C}-29 + n-{C}-31 + n-{C}-33 + n-{C}-35). {T}his index may therefore be used to analyse {C}entral {A}frican peat deposits and derive the relative abundance of {C}-3 and {C}-4 plant waxes in the past, independently of delta {C}-13 measurements. {F}urthermore, delta {C}-13 values from the central {C}ongo {B}asin and other {A}frican sites suggest that environments with high relative humidity (> 80%) are characterised by very negative delta {C}-13 values (i.e., < -37 parts per thousand) of n-{C}-29 and n-{C}-31 alkanes. {T}his observation highlights the potential of n-alkane delta {C}-13 in deriving climatic information under high relative humidity conditions in {C}entral {A}frican lowlands, and contribute to palaeo-climatic reconstructions. {F}inally, the delta {D} values of n-{C}-29 and n-{C}-31 alkanes demonstrate that, despite contrasting apparent fractionation values associated with photosynthetic pathways and plant functional types - which can be accounted for using delta {C}-13 and pollen data in sedimentary deposits - they reliably reflect the delta {D} of environmental water. {T}his confirms that plant wax n-alkane delta {D} values are effective tools for reconstructing palaeo-climatic changes in equatorial regions.},
  keywords = {{C}entral {C}ongo {B}asin ; {P}eatlands ; {P}lant wax ; n -{A}lkane ; {C}arbon isotopes ; {H}ydrogen isotopes ; {P}alaeo-environment ; {P}alaeo-climate ; {CONGO} {BASSIN}},
  booktitle = {},
  journal = {{O}rganic {G}eochemistry},
  volume = {212},
  numero = {},
  pages = {105092 [17 ]},
  ISSN = {0146-6380},
  year = {2026},
  DOI = {10.1016/j.orggeochem.2025.105092},
  URL = {https://www.documentation.ird.fr/hor/fdi:010095902},
}