Soumaya Belmecheri


I am a broadly trained stable isotope geochemist with research interests in climate and environmental reconstructions from lake sediments and tree-rings. My approach is to develop quantitative proxies in an interdisciplinary collaborative setting. Proxy-derived data are essential to evaluate and calibrate climate and carbon cycle models and to improve their predictive ability. I am also involved with research based in the department of Anthropology at PSU to estimate ages and growth rates of tropical hardwood trees from Central America using calcium concentration in wood (measured with LA-ICPMS) which is a proxy of precipitation seasonality. We have tested this technique on both extant trees and structural wood from a Mayan temple.



  • Estimating Forest Productivity Over Regional and Multi-Decadal Time Scales Using Carbon Isotopes in Tree Rings (NSF-BCS) will test the δ13C relationship between CO2 fluxes and C sequestration. My role as co-PI will be to study the spatial coherence of δ13C from tree-rings collected at 10 forest-sites along a transect that stretches from Harvard Forest to Howland Forest and to develop a long-term δ13C chronology as as proxy for long term carbon sequestration.
  • Paleoclimate, Paleoenvironment and Other Potential Drivers of Extinction of Mammuthus primigenius, St. Paul Island, Pribilof Islands, Alaska (Arctic System Program). My role in this project as a co-PI is to develop a calibration of the δ18O and D/H for chironomids and  lake water (to account for a potential vital offset) and use the isotopes to reconstruct past precipitation and temperature during the Holocene. 
  • Do fuel treatments restore ecosystem function? Water use efficiency before and after fire suppression and fuels treatments in fire-prone pine forests in the western United States (USDA). My role in this project as a co-PI is to use the δ13C from tree-rings to infer water use efficiency and use this proxy as a metric of ecosystem function from 1800 to 2012 at two FFS study sites (AZ, WA). 
  •  Georgian Ancient Transcaucasia: Environments and Societies (CNRS-France) I am currently working on the Javakheti Plateau in the republic of Georgia to characterize the impact of natural climate variations on the evolution of pre- and proto-historic societies in central Transcaucasia using lake sediments, with a special emphasis on the the transition Paleolithic-Neolithic between 15-8 ky B.P.


Research Interests

  • climate and environmental reconstructions from lake sediments and tree-rings


  • Ph.D. 2008 in geochemistry at the University of Paris XI-Orsay and the Laboratoire des Sciences du Climat et de l’Environement (LSCE)