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Resumo Este artigo investiga as mudanças no uso do solo e analisa seus impactos na temperatura da superfície em João Pessoa(PB entre os anos de 1991 e 2010. Neste estudo foram utilizadas imagens do TM/Landsat 5 para quantificar as mudanças no uso do solo e a variabilidade da temperatura da superfície em 1991, 2006 e 2010. As imagens foram pré-processadas usando técnicas de calibração e correções geométricas e atmosféricas. Para a classificação do uso do solo foi utilizado o método de classificação supervisionada, pela Máxima Verossimilhança. Cinco usos e ocupação do solo foram identificados (vegetação herbácea, urbano, vegetação arbórea/arbustiva, solo exposto e água). A integração de técnicas de Sensoriamento Remoto e Sistemas de Informações Geográficas foram ainda aplicados para examinar os impactos das mudanças do uso do solo nas temperaturas de superfície. Os resultados revelam uma mudança no uso do solo na área de estudo. As principais mudanças no uso do solo ocorreram nas classes área urbana e vegetação herbácea. Os maiores valores de temperatura da superfície foram estimados sobre as classes área urbana e solo exposto. Os resultados mostraram também uma maior variação da temperatura no período entre 2006(2010, devido ao fato do aumento da classe área urbana em praticamente todas as porções de João Pessoa.

RESUMO:A dengue é uma doença viral cujo número de casos aumentou consideravelmente nas últimas décadas em várias regiões do Brasil. ABSTRACT: Dengue is a viral disease whose incidence has increased considerably in recent decades. This study aimed to investigate the climatic factors associated with the incidence of dengue fever in the city of João Pessoa, Paraíba State, in the period between 2007 and 2011. The analysis has included thermo-rainfall collected in INMET, and the cases of dengue obtained in the Health Department of the municipality. In total were reported 9,467 confirmed cases of dengue, as follows: 33.2% in 2007, 8.8% in 2008, 2.6% in 2009, 12.4% in 2010, and 42.9% in 2011. The highest incidences of dengue cases occur in the south part of the city. It was found by correlating time-lag that rainfall and relative humidity are the climatic variables that favor the occurrence of dengue in João Pessoa.

Eco-environmental change prediction models are important decision tools for policy makers as they help to quantify environmental sensitivity and understand the relationship between human activities and environmental quality. Thus, this paper aims to analyze eco-environmental changes in Monteiro County, a semi-arid zone within northeastern Brazil. This study used means of satellite images, geographic information system and global position system techniques, topographic map, climatic data and soil maps, as well as field survey data. The result outputs were evaluated on their ability to accurately predict the most sensitive and least sensitive areas. The results showed that land cover changes have modified the environment in general, and two prominent environmental degradation processes were identified: land degradation, and low soil loss. The mean soil loss increased from 0.09 t ha−¹ yr−¹ in 1987 to 0.18 t ha−¹ yr−¹ in 2010, as an effect of vegetation gain and particularly the conversion of thousands of square kilometers of Tropophile forest middle slope and barren land into Tropophile forest plain and Tropophile forest high strand. Thus, this study provides insight on territorial ordering and management of environmental services with a regional perspective.

The EPM is a model for qualifying the erosion severity and estimating the total annual sediment yield. The EPM uses empirical coefficients (erodibility coefficient, protection coefficient and erosion coefficient) and a matrix of the basin physical characteristics. The EPM gives a quantitative estimation of erosion intensity as well as the estimation of sediment yield and transportation. To analyze the suitability of the Gavrilovic method for use with GIS techniques, we prepared cartographic data on geology, pedology, slope, temperature and land use in digital form. A raster-based Geographic Information System (GIS) was applied to generate the erosion-severity and sediment yield maps. In order to validate the EPM estimated erosion, data annual sediment yield were collected between 1999 and 2007. The results showed a mean sediment delivery ratio (SDR) of around 8% and a calculated mean sediment yield of 0.108 t/ha/year, which is close to the observed one, 0.169 t/ha/year. The obtained soil loss map could be considered as a useful tool for environmental monitoring and water resources management.

The main goals of this study are to better understand the spatial and temporal variabilities in rainfall and to identify rainfall trends and erosivity for the period from 1963 to 1991 in the Epitácio Pessoa reservoir catchment, which is located in Paraíba, northeastern Brazil. This study analyzes annual rainfall trends on a regional scale by using monthly data from 13 rainfall stations. For this purpose, the nonparametric Mann–Kendall and Sen methods were used in the analysis. Descriptive statistics methods and interpolation techniques were also used for spatial–temporal analysis of the annual rainfall. A detailed statistical analysis applied to the time series of all the stations indicates that the rainfall presents substantial annual spatial–temporal variability and a negative trend (decrease) in the mean rainfall at most of the rainfall stations in the catchment during the study period. The results only showed a positive trend for the Soledade and Pocinhos stations. The distribution of positive and negative trends in the Epitácio Pessoa reservoir catchment is extremely irregular, and the changes in the study area are more significant compared to those identified in other studies. Graphic abstract

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