Solos, ambiente e dinâmica climática da camada ativa na Peninsula Potter, Antártica Marítima

• Autor(a) principal: Poelking, Everton Luís
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1617
• topic: Criossolos; Monitoramento climático; Camada ativa; SIG; Criossolos; Climate monitoring; Active layer; SIG; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::CIENCIA DO SOLO

In this paper we report the main physical and chemical properties of criossolos to classify and map soils according WRB; relating the geo-environmental characteristics of the plant communities distribution in the ice-free areas of Potter Peninsula; investigate the climate dynamics in the region and relate with the thermal dynamics of temperature and humidity of criossolos in King George Island, Maritime Antarctic. Surveys of 18 soil profiles in 2008 were analyzed to physical-chemical characterization and classification of soils for the WRB. The geomorphology map of the peninsula was used as a basis for soil classes mapping. The vegetation mapping was obtained by the classification of a Quickbird image. It was also examined intra-seasonal variability of air temperature related rates of change of polar glacier retreat Club, through a series of nine scenes of Landsat satellite imagery and atmospheric temperature data from 1986-2010 from Jubany Weather Station. Based on data points of land, remote sensing techniques and GIS tools, we analyzed the spatial distribution of plant communities of Potter Peninsula, as well as determining factors. Finally the data were related to temperature and soil moisture in the region with climatic data to elucidate the dynamic thermal behavior of the active layer in relation to climate change. In general the soils of Potter have little physical, chemical and morphological characteristics very similar to the source material. The influence of bird activity contributes to ornithogênics soil formation. Although small patches restricted account for the activity of birds, mainly represent higher levels of P, C and N. Potter Peninsula plant communities occupy 23% of ice free area, occupying different landscape positions, indicating a reduction of diversity and biomass from the coastal to inland areas of the peninsula, where the sub-desert conditions prevail. There is a clear dependence between soil and topography on vegetation, soils with higher moisture or poorly drained acid, pH-neutral conditions are favorable for moss subformations; ornithogenics soil rich in organic matter near the penguin colonies have a greater biomass and diversity, with associations of mosses and grasses; felseenmeers stable and flat rock cryoplanations surfaces are the preferred sites for Himantormia lugubris and Usnea. Lichens Subformations and mosses cover the largest area of vegetation in different environments. The results of time series of air temperatures showed a consistent decline over the past 22 years the polar front Glacier Club, resulted in an increase of 120.47 ha of ice free area in Potter. During the 25 years studied, there was an increase in temperature of 1.64 °C in fall temperature, 1.58 °C temperatures in spring, 0.7 ºC in winter and 0.47 °C in summer. The influences of air temperature in glacier retreat demonstrate delay of about one year. Despite evidence of increasing average air temperature in the region in recent decades, the retract in front of the Polar Club glacier only with the range of atmospheric temperatures is not enough to explain the observed variation to the front of the glacier in Potter. The Informative Value method indicates a model's predictive capacity of around 89% for classes of algae and 87% for class of mosses and grasses. Other classes: Mosses, Lichens, Mosses and Lichens and also had satisfactory results with predictive capacity of 79, 78 and 71% respectively. This way one can say that the model has good predictive ability. The four sites studied are located in an altitude range that varies from 45 to 89 m, but the dynamic thermal during the study period showed slight differences due to specific characteristics of each soil influenced this behavior. Despite finding themselves in continuous permafrost zone, only two sites (S1 and S2) showed the presence possibly as early as the first 100 cm depth. The results presented here may contribute to future investigations of dynamic thermal modeling of the active layer and its behavior in the long term.