@article{fdi:010042709,
  title = {{D}istribution, shape and clonal growth of the rare endemic tree {O}lea europaea subsp laperrinei ({O}leaceae) in the {S}aharan mountains of {N}iger},
  author = {{A}nthelme, {F}abien and {A}bdoulkader, {A}. and {B}esnard, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he populations of the {L}aperrine's olive ({O}lea europaea subsp. laperrinei) are located in three main areas corresponding to the mountains of northern {N}iger ({A}ir), southern {A}lgeria ({H}oggar), and north-western {S}udan (western {D}arfur). {T}he populations native of {N}iger were found to occur in very fragmented patches from 1550 to 1850 m in five isolated mountains with population sizes not exceeding 100 trees each, except in the {T}amgak. {S}amples in the {T}amgak and the {B}agzane mountains were studied by combining field observations with identification of genets (using highly variable {DNA} marker analyzes). {T}rees were relatively small and multi-stemmed like those in the {H}oggar, and were associated with some tropical species as in the western {D}arfur. {T}hey were found on borders of "wadis", i.e., temporary water courses, in ravines and on hillsides. {T}hey were unable to rely on sexual reproduction, which was found to be ineffective. {I}n contrast, 28% of the genetic profiles found (n (genet) = 98) were represented with two or more trees without aboveground connections. {M}olecular and morphological data both demonstrated that the populations used clonal growth ({CG}) to survive in the current unfavorable period of hyper-aridity, and thus are likely to be remnant populations. {S}igns of human-related disturbances, recorded on 43% of the sampled trees, should be a determining factor of distribution as well. {I}n the {B}agzane mountains especially, where human activities are more intense than in the {T}amgak mountains, trees developed preferentially on hillsides and ravines with low access rather than on wadi borders with better edaphic conditions but easier access for livestock/people. {CG} may be therefore, a survival strategy both against aridity and human-related disturbances. {S}exual reproduction may be triggered during a less arid period, following the model of multiple demographic strategies, widespread in arid environments. {H}owever, survival would be affected by browsing and cuttings. {L}astly, the absence of an efficient sexual strategy coupled with the high fragmentation of very small populations and a narrow altitudinal range of distribution indicates that today the populations of {O}. e. laperrinei in the {A}ir mountain range are more endangered than those from southern {A}lgeria and north-western {S}udan.},
  keywords = {{A}rid ; {I}solation ; {H}abitat fragmentation ; {H}uman activities ; {M}icrosatellite markers ; {M}ultiple demographic strategy ; {R}emnant population},
  booktitle = {},
  journal = {{P}lant {E}cology},
  volume = {198},
  numero = {1},
  pages = {73--87},
  ISSN = {1385-0237},
  year = {2008},
  DOI = {10.1007/s11258-007-9386-6},
  URL = {https://www.documentation.ird.fr/hor/fdi:010042709},
}