@article{fdi:010040989,
  title = {{L}ong-term sunspot forcing of savanna structure inferred from carbon and oxygen isotopes},
  author = {{W}oodborne, {S}. and {M}{\'e}lice, {J}ean-{L}uc and {S}choles, {R}.{J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e used the delta(18) {O} and delta(13) {C} isotopes from a speleothem and {D}elta {C}-14 values from known age tree rings as proxies for vegetation structure, rainfall and sunspot activity over the last 10,000 years. {T}he delta {O}-18 and delta {C}-13 signals are significantly correlated and wavelet coherence analysis shows that a phase locked responses is only found to occur over periods less than 150 years. {T}he delta {C}-13 and {D}elta {C}-14 signals are also significantly correlated but the wavelet coherence analysis shows phase locked responses at periods in the order of 320 and 1100 years at various times in the past. {W}e conclude that savanna vegetation structure responds to rainfall over periods of decades to about 150 years, and to solar forcing over periods greater than 150 years. {W}e propose that elevated {UV}-{B} radiation at the earth surface during periods of low sunspot activity favours the productivity of {C}-4 plants over {C}-3 plants possibly because of the metabolic cost of structural adaptive responses and of producing {UV}-{B} absorbing compounds in the latter.},
  keywords = {},
  booktitle = {},
  journal = {{G}eophysical {R}esearch {L}etters},
  volume = {35},
  numero = {2},
  pages = {{NIL}_7--{NIL}_10},
  ISSN = {0094-8276},
  year = {2008},
  DOI = {10.1029/2007{GL}032019},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040989},
}