@article{fdi:010067670,
  title = {{C}ontradictory hydrological impacts of afforestation in the humid tropics evidenced by long-term field monitoring and simulation modelling},
  author = {{L}acombe, {G}. and {R}ibolzi, {O}livier and {D}e {R}ouw, {A}nneke and {P}ierret, {A}lain and {L}atsachak, {K}. and {S}ilvera, {N}orbert and {D}inh, {R}. {P}. and {O}range, {D}idier and {J}aneau, {J}ean-{L}ouis and {S}oulileuth, {B}. and {R}obain, {H}enri and {T}accoen, {A}. and {S}engphaathith, {P}. and {M}ouche, {E}. and {S}engtaheuanghoung, {O}. and {D}uc, {T}. {T}. and {V}alentin, {C}hristian},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he humid tropics are exposed to an unprecedented modernisation of agriculture involving rapid and mixed land-use changes with contrasted environmental impacts. {A}fforestation is often mentioned as an unambiguous solution for restoring ecosystem services and enhancing biodiversity. {O}ne consequence of afforestation is the alteration of streamflow variability which controls habitats, water resources, and flood risks. {W}e demonstrate that afforestation by tree planting or by natural forest regeneration can induce opposite hydrological changes. {A}n observatory including long-term field measurements of fine-scale land-use mosaics and of hydrometeorological variables has been operating in several headwater catchments in tropical southeast {A}sia since 2000. {T}he {GR}2{M} water balance model, repeatedly calibrated over successive 1-year periods and used in simulation mode with the same year of rainfall input, allowed the hydrological effect of land-use change to be isolated from that of rainfall variability in two of these catchments in {L}aos and {V}ietnam. {V}isual inspection of hydrographs, correlation analyses, and trend detection tests allowed causality between land-use changes and changes in seasonal streamflow to be ascertained. {I}n {L}aos, the combination of shifting cultivation system (alternation of rice and fallow) and the gradual increase of teak tree plantations replacing fallow led to intricate streamflow patterns: pluri-annual streamflow cycles induced by the shifting system, on top of a gradual streamflow increase over years caused by the spread of the plantations. {I}n {V}ietnam, the abandonment of continuously cropped areas combined with patches of mix-trees plantations led to the natural re-growth of forest communities followed by a gradual drop in streamflow. {S}oil infiltrability controlled by surface crusting is the predominant process explaining why two modes of afforestation (natural regeneration vs. planting) led to opposite changes in streamflow regime. {G}iven that commercial tree plantations will continue to expand in the humid tropics, careful consideration is needed before attributing to them positive effects on water and soil conservation.},
  keywords = {{VIET} {NAM} ; {LAOS}},
  booktitle = {},
  journal = {{H}ydrology and {E}arth {S}ystem {S}ciences},
  volume = {20},
  numero = {7},
  pages = {2691--2704},
  ISSN = {1027-5606},
  year = {2016},
  DOI = {10.5194/hess-20-2691-2016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010067670},
}