Stable isotope chronology and climate signal calibration in neotropical montane cloud forest trees

LDEO Publication: 
Publication Type  Journal Article
Year of Publication  2008
Authors  Anchukaitis, K. J.; Evans, M. N.; Wheelwright, N. T.; Schrag, D. P.
Journal Title  Journal of Geophysical Research-Biogeosciences
Volume  113
Issue  G3
Pages  -
Journal Date  Aug 30
ISBN Number  0148-0227
Accession Number  ISI:000258823000001
LDEO Publication Number  7160
Key Words  tree-rings; intraannual growth dynamics; point-reyes peninsula; oxygen-isotope; costa-rica; lowland deforestation; rainfall interception; tropical forest; water; cellulose; ratios

Tropical montane cloud forests are ecosystems intrinsically linked to a narrow range of geographic and meteorological conditions, making them potentially sensitive to small changes in precipitation or temperature. We investigate the potential application of stable isotope analysis to cloud forest dendroclimatology at Monteverde in Costa Rica in order to be able to extract both chronological and paleoclimate information from trees without annual growth rings. High-resolution delta O-18 measurements are used to identify regular cycles in wood of up to 9 parts per thousand, which are associated with seasonal changes in precipitation and moisture sources. The calculated annual growth rates derived from the isotope time series match those observed from long-term basal growth measurements. Interannual variability in the oxygen isotope ratio of lower forest trees is primarily related to interannual changes in wet season precipitation. Forward modeling independently supports our detection of both annual chronology and a climate signal. The confirmation of annual chronology and sensitivity to interannual climate anomalies suggests that tropical cloud forest dendroclimatology can be used to investigate local and regional hydroclimatic variability and change.


342ZVTimes Cited:0Cited References Count:74

URL  <Go to ISI>://000258823000001
DOI  Doi 10.1029/2007jg000613