Evaluation of tropical forests sensitivity to past climate changes (FORSENS)

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Forests are often described as the 'lungs of the Earth' because of the critical role they play within the planet's natural systems. However, concern for global forest ecosystems has been growing over recent decades because of the uncertainty related to how they will respond to the anticipated changes in climate. Tropical forests are critical to the functioning of planet Earth in terms of biodiversity, resource management and carbon storage. The complexity of tropical ecosystems means that their likely response to predicted future climate change is highly uncertain. The FORSENS project is aimed to improve the understanding of tropical forest dynamics. The research project is based on a comparison of forests dynamics through time (Last Glacial Maximum [c. 21,500 years ago] to the present) across an elevation and latitudinal gradient. The FORSENS project will examine biological remains contained within sediments cores from lakes to reconstruct past environmental change. The FORSENS project will develop two entirely new records of past environmental change (one from the Andean highlands and one from lower elevation on the eastern Andean flank) within the equatorial tropics. The two new sites are: 1) Lake Baños (Ecuador, 00o19.320'N-78o9.184'W, 3816 m asl) and, 2) A new record to be collected from W Amazonia lowlands (Colombia, Ecuador). In addition, two published records of past environmental change from the southern hemisphere tropics will be enhanced to create a network of four comparable sites across which past environmental changes can be assessed. The two enhanced sites are: 1) Lake Khomer Kotcha (Bolivia, 17o16.154'S-65o43.945'W, 4153 m asl[1] and, 2) Lake Consuelo (Peru, 13o57'S-68o59'W, 1360 m asl [2]).The examination of multiple proxies will allow different drivers of environmental change to be revealed. Key techniques applied will be fossil pollen (vegetation change), charcoal (fire history), non-biting midges (temperature and/or water quality), non-pollen palynomorphs (NPP; human impact) and biomarkers (plant community change). In addition, the non-biological composition will also be considered to provide insight into the depositional environment (loss-on-ignition, magnetic susceptibility, colour). Key indicators for human (crop pollen, charcoal or dung fungus) or climate (non-biting midges) drivers of change will be examined at each study site.The knowledge of past interactions between climate-vegetation-human will provide new insight into how future global climatic change could affect to tropical forests. To allow a comparable data set to be generated from all the records specific time intervals of known past climate change will be targeted: 1) the last deglaciation (21,500-11,700 years ago) and, 2) the Holocene Dry event (8,000-4,000 years ago). These time intervals have been characterised by the occurrence of rapid climatic shifts (e.g., an average warming around 4oC/century during the end of deglaciation) equivalent to those proposed for the near future. The analyses of the different biological proxies will allow possible future vegetation responses to predicted climatic changes to be anticipated. The research will be carried out by Dr Montoya assisted by expertise and facilities within the Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR) at The Open University (OU). Specifically the project will be hosted within the Palaeoenvironmental Change Research Laboratory (PCR) lead by Dr Gosling. Montoya will bring new skills related to NPP to The OU and will undertake training in the areas of non-biting midges and biomarkers. The FORSENS project will bring together the two currently unconnected professional networks of Montoya and Gosling to create a truly global network of specialists References1 Williams, JJ et al. 2011. Palaeogeography, Palaeoclimatology, Palaeoecology. doi:10.1016/j.palaeo.2011.10.0012 Bush, MB et al. 2004. Science 303, 827-829.