Metodologia de análise das relações entre dinâmica populacional, clima e vetores de mudança no semiárido brasileiro.

Abstract

The semi-arid region of northeastern part of Brazil has low precipitation rates and high natural climate variability. It appears trough extreme events such as prolonged droughts. The Caatinga biome has been under impacts either caused by human actions, as directly or indirectly caused by climate changes. For a better understanding and planning actions about those changes, susceptible areas could be classified and zoned, making possible a visualization of historical and continuous pressures caused by urban growth or other human pressures. This research uses bioclimatic data on a global scale and census data at the regional and local scale in an integrative approach. Geospatial technologies are used to obtain a “pressure for changes indicator” caused by climatic, demographic or socioeconomic variables. Fuzzy overlay techniques are used and a statistical estimator for generate surfaces (Kernel density) for three chosen drivers. One climate driver represented by Temperature, Precipitation and Precipitation Seasonality; One demographic driver represented by Population density and rural population changes; and one socioeconomic driver represented by HDI (Human development index) for each county and agricultural GDP (Gross Domestic Product). This overlay process results in a unique “Change for pressure” index for the Brazilian semi-arid region. The results show the nearest areas from some important middle cities such as “high pressure changes”. In those areas, it is possible to observe the strong correlation between LULCC and high density urban areas and an increasing of GDP (Gross Domestic Product for Livestock and Agriculture) in the last years as well.