Studies on Spodosols in tropical coastal tablelands are still scarce. This paper studied such soils on coastal tablelands and a marine sandbank, in the States of Paraiba and Pernambuco, in Northeastern Brazil. Physical, chemical and mineralogical analyses were performed in 14 soil profiles on mostly plain surfaces under sugarcane cultivation. With regard to drainage, most of the profiles were defined as moderate to poorly drained and groundwater was detected at a depth of 182, 85 and 74 cm in three […]

Brachiaria species, particularly B. humidicola, can synthesize and release compounds from their roots that inhibit nitrification, which can lead to changes in soil nitrogen (N) dynamics, mainly in N-poor soils. This may be important in crop-livestock integration systems, where brachiarias are grown together with or in rotation with grain crops. The objective of the present study was to determine whether this holds true in N-rich environments and if other Brachiaria species have the same effect. The soil N dynamics were […]

There are several interpretation methods for foliar nutrient analysis, and the critical level or nutrient sufficient range described in the literature are the most commonly used. However, an inclusion of methods that determine the normal nutrient ranges for specific regions (sites) can increase the efficiency of interpretation. The objective of this study was to compare normal nutrient ranges for sugarcane cultivation, determined by the methods ChM (Mathematical Chance), DRIS (Integrated System of Diagnosis and Recommendation) and CND (Compositional Nutrient Diagnosis), […]

In Brazil, Pinus species are grown on approximately 1.87 million hectares, usually on chemically poor soils. The present study investigated the mineralogy of sand, silt and clay fractions and estimated the mineral reserve of K by different chemical extraction methods in naturally K-poor soil under Pinus taeda L., in the State of Paraná, Brazil. In a 500 m2 area, five trees with large diameter (dominant trees) were selected, and trenches opened (depth 1.6 m) under the canopy of each tree. […]

In a no-tillage system, cover crops must be used that combine shoot dry matter production and nutrient recycling. The aim of this study was to evaluate shoot dry matter production, decomposition rate and macronutrient and silicon release from pigeonpea and pearl millet in monoculture and intercropping systems. A randomized block design was used with a 3 x 6 factorial arrangement, with four replications. The first factor consisted of three cover crops (pigeonpea, pearl millet and intercropping of these cover crops) […]

The use of cover crops has been suggested as an effective method to maintain and/or increase the organic matter content, while maintaining and/or enhancing the soil physical, chemical and biological properties. The fertility of Cerrado soils is low and, consequently, phosphorus levels as well. Phosphorus is required at every metabolic stage of the plant, as it plays a role in the processes of protein and energy synthesis and influences the photosynthetic process. This study evaluated the influence of cover crops […]

Most studies related to soil aggregation associate the effect of managements or land use types with the organic matter content. However, a direct evaluation of microorganisms and their processes in undisturbed soil allows a better understanding of the real effect of different managements. The objective of this study was to evaluate the changes induced by different types of land use (pasture, eucalyptus forest, araucaria forest, conventional tillage with carrot, and conventional tillage with pumpkin) on soil chemical properties (pH, Ca, […]

The grain yield of upland rice under no-tillage has been unsatisfactory and one reason could be the nitrate/ammonium balance in the soil. Cover crops and nitrogen fertilization can be used to change the nitrate/ammonium relation in the soil and improve conditions for the development of upland rice in the no-tillage (NT) system. The aim was to study the effect of cover crops and nitrogen sources on grain yield of upland rice under no tillage. The study was carried out on […]

The intercropping of Eucalyptus with legumes can promote an improvement of soil biological quality in degraded areas and also be advantageous for the species of the consortium. The aim of this study was to evaluate the influence of planting systems (monoculture and consortium) of Acacia mangium (AM), Sesbania virgata (SV) and Eucalyptus camaldulensis (EC) on the biological characteristics of the plants (dendrometric attributes) and specifically on the fauna in the litter and the surface soil layer (0-0.05 m). An experiment […]

In agriculture, the search for higher crop yields based on sustainable soil management has led to a gradual pursuit of knowledge of the variables related to production systems. The identification of the causes of variability of these properties has become a part of strategic planning in the sugar and ethanol industry. This study investigated the spatial variability of iron oxides in the clay fraction and its relationship to soil physical and chemical properties in different sugarcane cultivation systems in the […]