PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY;
NOV 1 2015.
Citações Web of Science:
Studies dealing with the reconstruction of Holocene climate change of tropical areas are scarce. Of these, multi-proxy investigations using peatlands are still absent. In this paper, we present the Holocene record of environmental changes in central-eastern Brazil reconstructed from a core sampled in Pau de Fruta mire (Serra do Espinhaco Meridional, Brazil). We combined palynological and geochemical analyses, supported by core stratigraphy,C-14 dating and multivariate statistics. The location of the mire is ideal because it is in an area which is directly associated with the South Atlantic Convergence Zone (SACZ). Six main phases of change suggested by vegetation and local and regional landscape dynamics were described. In phase I (similar to 10,000-7360 cal. yr BP) the climate was very wet and cold and was accompanied by soil instability in the mire catchment (severe local erosion) and the 8.2 ka event was easily recognizable by a large increase in the deposition of regional dust. Phase II (similar to 7360-4200 cal. yr BP) was characterized by wet and warm conditions, catchment soil stability and enhanced deposition of regional dust. In phase III (similar to 4200-2200 cal. yr BP), climate was dry and warm and soil erosion in the catchment increased again. In phase IV (similar to 2200-1160 cal. yr BP) dry and punctuated cooling was reconstructed, together with enhanced deposition of regional dust. Phase V (similar to 1160-400 cal. yr BP) reflects sub-humid climatic conditions (like the current climate), the lowest inputs of local and regional dust and the largest accumulation of peat in the mire. While in phase VI (<similar to 400 cal. yr BP) sub-humid conditions continued but both local and regional erosion significantly increased. Our results demonstrate that the tropical peatlands of Serra do Espinhaco Meridional contain relevant records of Holocene climate changes, and that a multi-proxy approach offers good opportunities for a detailed reconstruction of palaeoenvironments. (C) 2015 Elsevier B.V. All rights reserved. (AU)