Résumé
In semi-arid steppe regions, it is often difficult to understand the role of climatic change from Holocene pollen-based paleoclimate records alone. These records often contain low amounts of arboreal pollen and shifts in steppe vegetation can be subtitle making an ecological based interpretation difficult. This is further complicated in the Near East and Caucasus, where the long history of agriculture and pastoral have played a key role in shaping this vegetation. It is therefore necessary to utilize an independent proxy separate from vegetation to understand the role of climate in shaping the vegetation of the region. Increasingly, the use of the biomarker glycerol dialkyl glycerol tetraether (GDGT) has become a popular proxy for air temperature reconstruction. However, its usage in peat and small water bodies are still limited. The semi-arid to arid nature of many steppe regions, however, often means that large lake archives are not available. Thus, making cores from smaller mires and peatlands necessary to understand past climate change. For this poster, we will present our first results of our Holocene GDGT based mean annual air temperature (MAAT) reconstruction from the country of Armenia located in the Lesser Caucasus mountains. This record is 12,000 years old and has been taken from two cores extracted from small mires located next to the Mount Aragats, the highest peak in Armenia. Utilizing the well-known isoprenoid-GDGT and branched-GDGT but also newly discovered H-GDGTS we will present our Holocene dataset and evaluate its robustness. To help calibrate our reconstruction we utilize XRF data, published calibrations, and our own data calibrations from 9 core tops. These cores are taken from various peat and lacustrine sediments across Armenia and are combined with modern meteorological datasets. In addition, we will compare these datasets with our 10,000 year pollen record and pollen based climate reconstruction also from a core taken from the same area. Specifically, we will try and understand how possible changes in temperature, precipitation and seasonality recorded at 9000 and 4700 cal BP in our pollen climate reconstruction compares with our MAAT GDGT reconstruction. Together, these data will bring a broader understanding of the role of climate and humans in modifying these steppe ecosystems.