Correlation between physical and chemical characteristics of soils and their natural mercury content is important for identifying the parameters that most influence Hg retention in these soils and its distribution in different environmental compartments. The aim of this study was to quantify the Hg content of tropical soils without anthropogenic influence and correlate it with physical and chemical soil characteristics. The present study is relevant because most research focuses on contaminated soils and, in the case of tropical soils, research […]

Although the State of Parana, Brazil, has adopted crop rotation and no-till (NT) systems, fertilizer application is still based on recommendations developed more than 30 years ago for monocropping under conventional tillage because fertilizer recommendations developed specifically for crop rotation under NT are lacking. The objective of our study was to consolidate P calibration and evaluate crop responses to P fertilization so as to propose a system of technical recommendations for P fertilization for soybean, maize, wheat, and barley grown […]

Eucalyptus requires large amounts of nitrogen (N); however, it responds in diverse manners to the application of this nutrient. The aim of this study was to evaluate the differential performance in growth, mineral nutrition, and gas exchanges of N-fertilized Eucalyptus clones. The treatments consisted of two Eucalyptus clones (VM-01 and I-144) and six N application rates (0, 0.74, 2.93, 4.39, 5.85, and 8 mmol L-1 NH4NO3) arranged in a randomized complete block design with five replications. VM-01 had greater plant […]

The Brazilian savanna is a mosaic of phytophysiognomies influenced by edaphic and topographic factors that range from the occurrence of fires to anthropic disturbance. The goal of this study was a comparative analysis between two cerrado areas in southeastern Goiás, relating the floristic composition and structure of the vegetation to soil properties to better understand the physiognomic characteristics of the region. Twenty-five 20 × 20 m plots were used. All plants with circumference at breast height of more than 15 […]

Quantification of soil physical quality (SPQ) and pore size distribution (PSD) can assist understanding of how changes in land management practices influence dynamics of soil structure, and this understanding could greatly improve the predictability of soil physical behavior and crop yield. The objectives of this study were to measure the SPQ index under two different land management practices (the continuous arable cropping system and natural bush fallow system), and contrast the effects of these practices on the structure of PSD […]

Air permeability may be used as a soil physical quality indicator. The objective of this study was to determine the air permeability and pore continuity index for the seedbed of an Oxisol cultivated under a no-tillage system that underwent mechanical chiseling and biological promotion of pore formation using the forage radish crop. The study was carried out in an experimental area of the Universidade Estadual de Ponta Grossa (Ponta Grossa State University), Parana, Brazil. The treatments were 18 consecutive years […]

In production systems such as the integrated crop-livestock system (ICL) under no-tillage, improvements have been observed in chemical, physical, and biological soil properties. Therefore, we aimed to evaluate the changes in chemical and physical soil properties, as well as carbon (C) accumulation, in an Oxisol under irrigated conditions in the Cerrado (Brazilian tropical savanna) in an ICL system under no-tillage. The experiment was carried during the growing of 2010/2011, 2011/2012, and 2012/2013. A randomized block experimental design with four replications […]

Management of forage grazing height by cattle may compromise soil physical properties. The objective of this study was to evaluate the influence of grazing height of brachiaria (Urochloa ruziziensis) and the average stocking rate, after three years into an integrated soybean crop-livestock system, in the physical attributes of a Haplorthox (Rhodic Ferralsol). A randomized complete block experimental design with three replications was used. Five treatments were evaluated in 1 ha experimental plots: grazing heights of 10, 20, 30, and 40 […]

Alternative copper (Cu) sources could be used in fertilizer production, although the bioavailability of copper in these materials is unknown. The objective of this study was to evaluate the extractants neutral ammonium citrate (NAC), 2 % citric acid, 1 % acetic acid, 10 % HCl, 10 % H2SO4, buffer solution pH 6.0, DTPA, EDTA, water, and hot water in the quantification of available Cu content in several sources, relating them to the relative agronomic efficiency (RAE) of wheat grown in […]

Melon is one of the most demanding cucurbits regarding fertilization, requiring knowledge of soils, crop nutritional requirements, time of application, and nutrient use efficiency for proper fertilization. Developing support systems for decision-making for fertilization that considers these variables in nutrient requirement and supply is necessary. The objective of this study was parameterization of a fertilizer recommendation system for melon (Ferticalc-melon) based on nutritional balance. To estimate fertilizer recommendation, the system considers the requirement subsystem (REQ), which includes the demand for […]