@article{PAR00030806,
  title = {{H}ow to mitigate the effect of observer error when unraveling species-environment associations ? {A} case study with tropical tree communities from {W}estern {C}entral {A}frica},
  author = {{K}lein, {J}. {L}. and {S}t{\'e}vart, {T}. and {T}exier, {N}. and {B}oupoya, {A}. and {A}kouangou, {E}. and {D}arar, {R}. {K}. and {D}auby, {G}illes and {I}kabanga, {D}. {U}. and {B}ikoukou, {L}. {C}. {M}. and {N}guema, {D}. and {D}rouet, {T}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A}ims {U}nraveling species-environment associations proves challenging in species-rich tropical rainforests due to erroneous species identifications (observer error, {OE}), which negatively affect multivariate analyses. {OE} occurs more frequently at species level-confusing one species with another-than at broader taxonomic depth (genus or family) and disproportionately affects rare species. {T}herefore, many studies broaden the taxonomic resolution (using genus or family as surrogates for species) or remove rare species prior to analysis. {H}owever, it remains unclear which approach best mitigates the effect of {OE}.{L}ocation {G}abon.{M}ethods {W}e used a dataset comprising 19,287 trees in 99 forest plots across {G}abon and introduced increasing proportions of {OE} at species, genus and family depth. {W}e used redundancy analysis to quantify the overall strength of species-environment associations as adjusted {R}2 and quantified the relative importance of predictors as ratios between partial {R}2 for soil, climate, human activity and spatial predictors, at species, morphospecies, genus and family resolution. {W}e modelled {R}2 decline through exponential decay functions and tested for differences across depth and resolution using two-way {ANOVA}. {W}e compared {R}2 decay after independently introducing {OE} among rare and common species.{R}esults {R}2 declined consistently under {OE}. {M}odels remained significant to 30%-60% error rate, depending on depth or taxonomic resolution. {R}elative predictor importance was altered only when error proportions exceeded 75%. {A}nalysis at genus or family resolution caused {R}2 decay to steepen. {W}hen introduced among rare species, {R}2 decay was less pronounced. {P}aradoxically, rare species contributed little to {R}2 despite having stronger associations with the environment.{C}onclusion {M}oderate to high instances of observer error jeopardise our ability to detect significant species-environment associations. {B}roadening taxonomic resolution and removing rare species inflates {R}2 due to dimensionality reduction. {T}o mitigate the effect of {OE}, we recommend analysing floristic datasets at fine taxonomic resolutions (species or morphospecies) and retaining rare species.},
  keywords = {{C}entral {A}frica ; niche breadth ; observer error ; rare species ; species-environment associations ; taxonomic resolution ; tropical forest ; {AFRIQUE} {CENTRALE}},
  booktitle = {},
  journal = {{J}ournal of {V}egetation {S}cience},
  volume = {37},
  numero = {1},
  pages = {e70106 [ 15 ]},
  ISSN = {1100-9233},
  year = {2026},
  DOI = {10.1111/jvs.70106},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00030806},
}