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Assessing the dynamics of land use is important in providing quantified estimates of the extent of ecosystem change, and so and structured planning to reduce its environmental and social impacts.

The usage of spatial tools might be helpful in the optimization of decision-making regarding soil management, with technologies that assist in the interpretation of information related to soil fertility. Therefore, the present study evaluated the spatial variability of chemical attributes of the soil under an agroforestry system compared to a native forest in the municipality of Tomé-açu, Eastern Amazon, Brazil. Soil samples were performed at 36 points arranged in a 55 x 55 m grid. The soils were prepared and submitted to analysis in order to determine pH in H2O, exchangeable calcium, magnesium, potassium and aluminium, available phosphorus, potential acidity, organic matter, bases saturation and aluminium saturation. For each soil attribute, the spherical, gaussian and exponential models were adjusted. After the semivariograms fitting, data interpolation for assessment of spatial variability of the variables was performed through ordinary kriging.  The spherical and gaussian models were the most efficient models in estimation of soil attributes spatial variability, in most cases. Most of variables presented a regular spatial variability in their respective kriging maps, with some exceptions. In general, the kriging maps can be used, and we can take them as logistical maps for management and intervention practices in order to improve the soil fertility in the study areas. The results principal components indicate the need for integrated management of soil chemical attributes, with localized application of acidity correctors, fertilizers and other types of incomes, using the spatial variability of these fertility variables.

RESUMO: O presente trabalho teve como objetivo avaliar a dinâmica do uso do solo, entre os anos de 1984 e 2015, por meio do processamento digital de imagens, e aplicação de questionários para avaliar a relação do uso do solo com a qualidade de vida dos moradores da ilha de Caratateua, Belém, Pará. Foram utilizadas imagens do satélite LANDSAT-5, bandas 3, 4 e 5, dos anos 1984, 1999, 2008 e 2015, as quais foram submetidas à classificação supervisionada por máxima verossimilhança. Posteriormente, obteve-se mapas com classes de uso do solo, sendo mais expressivas a Vegetação Densa, Capoeira (Floresta Secundária), Solo Exposto e Área Urbana. Foram aplicados 50 questionários com a pergunta: Quais os principais problemas que interferem na qualidade de vida da população da ilha de Caratateua? O período entre os anos de 1984 a 1989 foi o de maior crescimento urbano na ilha. A falha na gestão ambiental e urbanística, associados ao processo de crescimento desordenado, que, aliado a outros fatores, resultou no aumento desordenado de áreas urbanas e vem gerando impactos sociais, em especial com o aumento da violência e da carência de saneamento básico, e ambientais, por meio do uso indiscriminado dos recursos naturais e do solo.PALAVRAS-CHAVE: Monitoramento ambiental, Processamento de imagens digitais,  Sensoriamento remoto.