ABSTRACT The removal of original vegetation for crops and pasture production and then followed by natural regeneration is a standard practice in the Atlantic Forest, which has produced patches with different degrees of degradation and regeneration across the landscape. The aim of this study was to evaluate the effects of replacement of native forest by pasture and natural regeneration of vegetation on soil and on soil organic matter (SOM) dynamics in the dry and rainy season in an Atlantic Forest […]

ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L.) plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC) and was fractionated in forms related to low (Feo) and high (Fed) crystallinity pedogenic […]

ABSTRACT In no-tillage (NT) systems, there is no plowed layer since the soil is not tilled. Thus, the soil layer for fertility evaluation can be defined as the one in which the fertility indices are affected by the surface application of lime and fertilizers and soil properties have the closest relationship with crop yields. The objective of this study was to determine the most appropriate soil layer under long-term NT for sampling for fertility evaluation in the South-Central region of […]

ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense) of Brazil. The treatments, which included mowed natural rangeland (NR), burned natural rangeland (BR), natural rangeland improved through the introduction of plant species after harrowing (IH), and natural rangeland improved through the introduction of plant […]

ABSTRACT Quantification of ammonia volatilization after addition of animal residues and nitrogen (N) mineral fertilizers to the soil is important for N management in fertilization programs. The objective of this study was to evaluate the effect of adding a urease inhibitor to N fertilizers to minimize ammonia losses following soil application. The experiment was carried out in a laboratory with samples of a Brazilian Oxisol containing 790 g kg-1 clay and 23 g kg-1 organic matter. Treatments consisted of addition […]

ABSTRACT Soil fertility evaluation through soil analysis traditionally does not consider interaction among elements. To include the interaction effect in interpretation of soil analyses, an experiment was conducted to evaluate the effect of nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg N per plant per cycle) with urea (45 % N) and potassium fertilization (0, 0.55, 1.1, and 2.2 kg K2O per plant per cycle) with potassium chloride (60 % K2O) on soil cationic balance. The experiment was carried out […]

ABSTRACT Fertilization programs for annual crops in the state of Paraná, southern Brazil, are based on studies that focused on conventional tillage and were established more than 30 years ago. The primary purpose of this study was to assess potassium (K) fertilization on long-term (>30 years) no-tillage soybean, corn, wheat, and barley crops grown in rotation on Oxisols in the central-southern region of Paraná. A total of 47 experiments were carried out from 2008 to 2013, three of which addressed […]

ABSTRACT Water erosion is the process of disaggregation and transport of sediments, and rainfall erosivity is a numerical value that expresses the erosive capacity of rain. The scarcity of information on rainfall erosivity makes it difficult or impossible to use to estimate losses occasioned by the erosive process. The objective of this study was to develop Artificial Neural Networks (ANNs) for spatial interpolation of the monthly and annual values of rainfall erosivity at any location in the state of Rio […]

ABSTRACT Oxidic soils are phosphorus drains in soil; hence, P availability is a limiting factor in tropical, weathered Oxidic soils. It has been shown that some brachiarias grown as cover crops may increase soil available P to subsequent crops. The objective of this study was to evaluate soil P cycling and availability, as well as the response of soybean to soluble and natural reactive phosphates as affected by ruzi grass (Urochloa ruziziensis, R. Germ. and C.M. Evrard, Crin) grown as […]

ABSTRACT Organic fertilizers derived from poultry litter and pig slurry are alternatives to mineral fertilizers in increasing soil nutrient availability. The aim of this study was to evaluate soil response, through characterization of organic C and available N, P, and K contents, and corn yield response to increasing amounts of poultry litter, pig slurry, and mineral fertilizers in an integrated crop-livestock production system (ICL) from 2011 to 2013. The experimental design consisted of randomized blocks in a 4 × 3 […]