Characterization of properties and main processes related to the genesis and evolution of tropical mountain mires from Serra do Espinhaço Meridional, Minas Gerais, Brazil

The properties and components of the peat allow peatlands to function as water reservoirs which participate in the hydrological cycle by modulating water discharge. In particular, mountain peatlands from Serra do Espinhaço Meridional (Minas Gerais State, Brazil) provide water of good quality for the nearby cities and also serve as habitats for wildlife and flora, with unique endemic species. In this paper, we present the characterization of four mountain mires (Pau de Fruta, São João da Chapada, Pinheiros and Sempre Viva) based on morphological, physical, chemical, and elemental properties analyzed in five selected peat cores (PdF-I, PdF-II, SJC, PI and SV). Radiocarbon dating indicates that they started to form during the late Pleistocene. Principal components analysis was applied to synthesize their main peat properties and underlying processes. The first principal component, PC1, is related to the relative content in inorganic versus organic matter of the peat, most probably related to the evolution of the soils of the mires' catchments (i.e. soil erosion); PC2 seems to be related to the incorporation of inorganic material by deposition of dust from regional sources; PC3 reflects the content and preservation of plant remains; and PC4 indicates the degree of peat decomposition. Our results suggest that mountain tropical mires from Serra do Espinhaço Meridional are complex peatland ecosytems, with a large potential for the reconstruction of environmental changes (i.e. climate change) occurred since the late Pleistocene, and that they should be fully protected. •The properties are comparable to those of other mountain peatlands.•The properties show variations in depth and in agreement with the stratigraphy.•The analyzed properties have to be conceived as proxies of the processes/drivers.•Four main processes are related to the genesis and evolution these mires.•These late Pleistocene mires should be preserved and protected in full.