Spatial dependence of soil physical attributes in of Alfissol forest | Variabilidade espacial dos atributos físicos em um Argissolo Vermelho sob floresta

English. This study aim to evaluate the spatial variability of soil physical attributes in of Alfissol forest inManicoré region, AM. The mapping of an agroforestry growing area of 70x70m was made using aregular grid sampling of 10 x 10m. In each grid , soil samples were collected at 0.0 – 0.2 and 0,40 –0,60 m depth, with a total of 128 sample points. Physical analyses were made (texture, soil bulk andparticles density, macro and microporosity, total porosity and aggregates stability in water).Withthe exception of DMG, DMP and class aggregates <1.00 mm had all the physical attributes spatialdependence structure ranging from moderate to weak. Values were above the range establishedin the mesh (12.00 to 45.56 m), enabling to make a basis for future studies in forest area. The physicalattributes presented in kriging maps different spatial behavior, however there are relationshipsbetween these attributes shown by geostatistics proving that this is effective tool for studies in forestarea.

Portuguese. O presente trabalho teve como objetivo avaliar a variabilidade espacial dos atributos físicos em umArgissolo Vermelho sob floresta na região de Manicoré, AM. Foi realizado um mapeamento de umaárea sob floresta nativa delimitando-se dentro da área uma subárea de 70 x 70 m. Nesta subáreaforam coletadas amostras de solos numa grade amostral regular de 10 x 10 metros nas profundidadesde 0,0 – 0,20 e 0,40 – 0,60 m, totalizando 128 pontos amostrais. Foram realizadas análises físicas(textura, densidade do solo e de partículas, macroporosidade, microporosidade, porosidade totale estabilidade dos agregados em água). Com exceção do DMG, DMP e classe de agregados<1,00 mm todos os atributos físicos apresentaram estrutura de dependência espacial variando demoderada a fraca. Os valores de alcance foram superiores ao estabelecido na malha (12,00 a45,56 m), tornando-se base para futuros estudos em área de floresta na Amazônia. Os atributosfísicos apresentaram mapas de krigagem com diferente comportamento espacial, havendo, noentanto relações entre estes atributos, evidenciando assim a eficiência desta ferramenta em áreade floresta. Spatial dependence of soil physical attributes in of Alfissol forest AbstractThis study aim to evaluate the spatial variability of soil physical attributes in of Alfissol forest inManicoré region, AM. The mapping of an agroforestry growing area of 70x70m was made using aregular grid sampling of 10 x 10m. In each grid , soil samples were collected at 0.0 – 0.2 and 0,40 –0,60 m depth, with a total of 128 sample points. Physical analyses were made (texture, soil bulk andparticles density, macro and microporosity, total porosity and aggregates stability in water).Withthe exception of DMG, DMP and class aggregates <1.00 mm had all the physical attributes spatialdependence structure ranging from moderate to weak. Values were above the range establishedin the mesh (12.00 to 45.56 m), enabling to make a basis for future studies in forest area. The physicalattributes presented in kriging maps different spatial behavior, however there are relationshipsbetween these attributes shown by geostatistics proving that this is effective tool for studies in forestarea.