2 results

Index of soil physical quality of hardsetting soils on the brazilian coast

Herdjania Veras de Lima, Álvaro Pires da Silva, Neyde Fabíola Balarezzo Giarola, Sílvia Imhoff

01/Dec/2014

Many soils have a hard-setting behavior, also known as cohesive or “coesos”. In such soils, the penetration resistance increases markedly when dry and decreases considerably when moist, creating serious limitations for plant emergence and growth. To evaluate the level of structure degradation in hard-setting soils with different texture classes and to create an index for assessing soil hardness levels in hard-setting soils, six soil representative profiles were selected in the field in various regions of Brazil. The following indices were […]

Fragipans and duripans of the low coastal plateau depression in Northeastern Brazil: an evolution proposal

H. F. Filizola, M. Lamotte, E. Fritsch, R. Boulet, J. C. Araujo Filho, F. B. R. Silva, [...]

01/Dec/2001

Fragipans and Duripans are frequently found in soils developed from sediments of the Barreiras Formation, in the low coastal plateaus of northeastern Brazil. Previous studies in arid regions have attributed Duripan cohesion to the amorphous silica. However, the Duripans and Fragipans in northeastern Brazil are located in semi-arid and high annual precipitation level zones (1.500 to 2.000 mm year-1). This study, based on a detailed characterization of soils from four depressions with different sizes, aimed to propose an evolution scheme […]