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Carbon and Nitrogen Stocks and Humic Fractions in Brazilian Organosols

Gustavo Souza Valladares, Marcos Gervasio Pereira, Vinícius de Melo Benites, Lúcia Helena Cunha dos Anjos, Adierson Gilvani Ebeling, Roni Fernandes Guareschi

17/Oct/2016

ABSTRACT Despite limited geographic expression of Organosols in Brazil, their high carbon storage capacity and natural environmental vulnerability justifies further studies on C and N stocks in these soils and their relationship to the nature of organic matter. Evaluation of physical and chemical properties of organic soils and their ability to store C is important so as to develop sustainable management practices for their preservation. The objectives of the study were to measure the total organic carbon stock (OCst), total […]

Characterization of Organic Matter under Different Pedoenvironments in the Viruá National Park, in Northern Amazon

José Frutuoso do Vale, Steven Nicodem, Valdinar Ferreira Melo, Sandra Catia Pereira Uchôa, Diego Lima de Sousa Cruz

12/May/2016

ABSTRACT Soil organic matter (SOM) fractions result from a variety of environmental processes, which affect incorporation and production rates, decomposition, alteration, and/or mineralization of organic matter. The aim of this study was to characterize SOM under the environments of rain forest, wooded campinarana (grasslands), arboreal-shrubby campinarana, grassy-woody campinarana, and pioneer plants of the Viruá National Park, in the north of the Brazilian Amazon. After chemical and physical characterization and soil classification, total organic carbon (TOC), total N, microbial activity, organic […]

Thermodynamic Characterization of Humic Acid-surfactant Interaction: New Insights into the Characteristics and Structure of Humic Acids

Leonardus Vergütz, Luis Henrique Mendes da Silva, Roberto Ferreira Novais, Maria do Carmo Hespanhol da Silva, Aparecida Barbosa Mageste, Ivo Ribeiro Silva

01/Dec/2015

ABSTRACT Humic acids (HA) are a component of humic substances (HS), which are found in nearly all soils, sediments, and waters. They play a key role in many, if not most, chemical and physical properties in their environment. Despite the importance of HA, their high complexity makes them a poorly understood system. Therefore, understanding the physicochemical properties and interactions of HA is crucial for determining their fundamental role and obtaining structural details. Cationic surfactants are known to interact electrostatically and […]

ORGANIC MATTER FRACTIONS IN A QUARTZIPSAMMENT UNDER CULTIVATION OF IRRIGATED MANGO IN THE LOWER SÃO FRANCISCO VALLEY REGION, BRAZIL

José Alberto Ferreira Cardoso, Augusto Miguel Nascimento Lima, Tony Jarbas Ferreira Cunha, Marcos Sales Rodrigues, Luis Carlos Hernani, Andre Julio do Amaral, [...]

01/Jul/2015

Improper land use has lead to deterioration and depletion of natural resources, as well as a significant decline in agricultural production, due to decreased soil quality. Removal of native vegetation to make way for agricultural crops, often managed inadequately, results in soil disruption, decreased nutrient availability, and decomposition of soil organic matter, making sustainable agricultural production unviable. Thus, the aim of the present study was to evaluate the impact of growing irrigated mango (over a 20 year period) on the […]

SOIL ORGANIC MATTER FRACTIONS IN PRESERVED AND DISTURBED WETLANDS OF THE CERRADO BIOME

Ricardo Fernandes de Sousa, Eliana Paula Fernandes Brasil, Cícero Célio de Figueiredo, Wilson Mozena Leandro

01/Jan/2015

Veredas are humid tropical ecosystems, generally associated to hydromorphic soils and a shallow water table. The soils of these ecosystems are affected by the use of the areas around these veredas. The objective of this study was to determine soil organic matter (SOM) fractions in veredas adjacent to preserved (native savanna) and disturbed environments (agricultural areas and pastures) in the Cerrado biome. Soil samples were collected from the 0-10 and 10-20 cm layers along reference lines drawn along the relief […]

CHROMIUM IN SOIL ORGANIC MATTER AND COWPEA AFTER FOUR CONSECUTIVE ANNUAL APPLICATIONS OF COMPOSTED TANNERY SLUDGE

Mara Lucia Jacinto Oliveira, Ademir Sérgio Ferreira de Araujo, Wanderley José de Melo

01/Jan/2015

Tannery sludge contains high concentrations of inorganic elements, such as chromium (Cr), which may lead to environmental pollution and affect human health The behavior of Cr in organic matter fractions and in the growth of cowpea (Vigna unguiculata L.) was studied in a sandy soil after four consecutive annual applications of composted tannery sludge (CTS). Over a four-year period, CTS was applied on permanent plots (2 × 5 m) and incorporated in the soil (0-20 cm) at the rates of […]