@article{fdi:010077382,
  title = {{D}rought-induced regime shift and resilience of a {S}ahelian ecohydrosystem},
  author = {{W}endling, {V}alentin and {P}eugeot, {C}hristophe and {M}ayor, {A}. {G}. and {H}iernaux, {P}. and {M}ougin, {E}. and {G}rippa, {M}. and {K}ergoat, {L}. and {W}alcker, {R}. and {G}alle, {S}ylvie and {L}ebel, {T}hierry},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {S}ahel (a semi-arid fringe south of the {S}ahara) experienced a long and prolonged drought from the 1970s to the mid-1990s, with a few extremely severe episodes that strongly affected ecosystems and societies. {L}ong-term observations showed that surface runoff increased during this period, despite the rainfall deficit. {T}his paradox stems from the soil degradation that was induced by various factors, either directly linked to the drought (impact on vegetation cover), or, in places, to human practices (land clearing and cropping). {S}urface runoff is still increasing throughout the region, suggesting that {S}ahelian ecohydrosystems may have shifted to a new hydrological regime. {I}n order to explore this issue, we have developed a simple system dynamics model incorporating vegetation-hydrology interactions and representing in a lumped way the first order processes occurring at the hillslope scale and the annual timestep. {L}ong term observations on a pilot site in northern {M}ali were used to constrain the model and define an ensemble of plausible simulations. {T}he model successfully reproduced the vegetation collapse and the runoff increase observed over the last 60 years. {O}ur results confirmed that the system presents two alternative states and that during the drought it shifted from a high-vegetation/low-runoff regime to the alternative low-vegetation/high-runoff one, where it has remained trapped until now. {W}e showed that the mean annual rainfall deficit was sufficient to explain the shift. {A}ccording to the model, vegetation recovery and runoff reduction are possible in this system, but the conditions in which they could occur remain uncertain as the model was only constrained by observations over the collapse trajectory. {T}he study shows that the system is also sensitive to the interannual and decadal variability of rainfall, and that larger variability leads to higher runoff. {B}oth mean rainfall and rainfall variability may increase in central {S}ahel under climate change, leading to antagonist effects on the system, which makes its resilience uncertain.},
  keywords = {{S}ahel ; eco-hydrology ; alternative stable states ; regime shifts ; rainfall ; variability ; {MALI} ; {SAHEL}},
  booktitle = {},
  journal = {{E}nvironmental {R}esearch {L}etters},
  volume = {14},
  numero = {10},
  pages = {105005 [12 ]},
  ISSN = {1748-9326},
  year = {2019},
  DOI = {10.1088/1748-9326/ab3dde},
  URL = {https://www.documentation.ird.fr/hor/fdi:010077382},
}