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48 results

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 […]

Cover plants and mineral nitrogen: effects on organic matter fractions in an oxisol under no-tillage in the cerrado

Isis Lima dos Santos, Carla Ferreira Caixeta, Alex Antônio Torres Cortês de Sousa, Cícero Célio de Figueiredo, Maria Lucrécia Gerosa Ramos, Arminda Moreira de Carvalho

01/Dec/2014

Cover plants are essential for the sustainability of no-tillage systems in tropical regions. However, information on the effects of these plants and N fertilization on soil organic matter fractions is still scarce. This study evaluated the effect of cover crops with different chemical composition and of N topdressing on the labile and humified organic matter fractions of an Oxisol of the Cerrado (savanna-like vegetation). The study in a randomized complete block design was arranged in split-plots with three replications. Four […]

Humic Haplustox under different land uses in a high altitude environment in the Agreste region of Pernambuco, Brazil

Jane Kelly Silva Araujo, Mateus Rosas Ribeiro, Marcelo Metri Corrêa, Izabel Cristina de Luna Galindo, Valdomiro Severino de Souza Júnior

01/Aug/2014

The Garanhuns Plateau in the Agreste region of the State of Pernambuco, Brazil is characterized by humid climatic conditions due to orographic rains, unlike the surrounding semiarid region. These soils are subjected to intense agricultural use and are extremely important for the regional economy. This study was carried out in the municipality of Brejão in the Agreste region with the aim of assessing changes in humic Haplustox soils subjected to different land uses. Four plots with different vegetation covers (native […]

Quality of soil organic matter under coffee intercropped with green manure

Marino Salgarello Coelho, Eduardo de Sá Mendonça, Paulo César de Lima, Gabriel Pinto Guimarães, Irene Maria Cardoso

01/Dec/2013

The input of organic residues associated with the humification process promotes improvement of soil properties and enables the sustainability of the production system. Aside from supplying the coffee with nutrients, pulse crops can improve the quality of soil organic matter by forming humic substances. The purpose of this study was to evaluate the effect of green manures legumes on the quality of humic substances in soils under coffee under two environmental conditions in the region of Zona da Mata, in […]

Organic matter quality and dynamics in tropical soils amended with sugar industry residue

Jader Galba Busato, Tairone Paiva Leão, Marihus Altoé Baldotto, Luciano Pasqualoto Canellas

01/Aug/2012

Soil organic matter depletion caused by agricultural management systems have been identified as a critical problem in most tropical soils. The application of organic residues from agro-industrial activities can ameliorate this problem by increasing soil organic matter quality and quantity. Humic substances play an important role in soil conservation but the dynamics of their transformations is still poorly understood. This study evaluated the effect of compost application to two contrasting tropical soils (Inceptisol and Oxisol) for two years. Soil samples […]

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