3290 results

Capture Time of Soil Mesofauna and Its Reflections on Interpretation of Indices for Characterizing the Soil Community

Luiz Rodrigues Freire, Ednaldo da Silva Araújo, Ricardo Luís Louro Berbara

01/Sep/2015

ABSTRACT Soil mesofauna consists of organisms that measure from 0.100 μm to 2 mm, being important to evaluate methods employed for its characterization. The objectives of this study were to define how long the soil material must remain in the Berlese-Tüllgren extraction device to capture organisms of the mesofauna and determine the minimum extraction time for correct use of the Shannon, Simpson, Pielou, and Margalef indices used to evaluate the diversity, dominance, and richness of the mesofauna communities. The study […]

Liming in Agricultural Production Models with and Without the Adoption of Crop-Livestock Integration

Francisco Carlos Mainardes da Silva, Luís Guilherme Sachs, Inês Cristina Batista Fonseca and, João Tavares

01/Sep/2015

ABSTRACT Perennial forage crops used in crop-livestock integration (CLI) are able to accumulate large amounts of straw on the soil surface in no-tillage system (NTS). In addition, they can potentially produce large amounts of soluble organic compounds that help improving the efficiency of liming in the subsurface, which favors root growth, thus reducing the risks of loss in yield during dry spells and the harmful effects of “overliming”. The aim of this study was to test the effects of liming […]

Occurrence and Structure of Arbuscular Mycorrhizal Fungal Communities in Cassava after Cultivation of Cover Crops as Observed by the “PCR-DGGE” Technique

Elaine dos Santos Heberle, Rafael Dutra de Armas, Daniel Alexandre Heberle, Sidney Luiz Stürmer, Luiz Augusto Martins Peruch, Paulo Emílio Lovato, [...]

01/Sep/2015

ABSTRACT Cassava (Manihot esculenta Crantz) is a highly mycotrophic crop, and prior soil cover may affect the density of arbuscular mycorrhizal fungi (AMFs), as well as the composition of the AMFs community in the soil. The aim of this study was to evaluate the occurrence and the structure of AMFs communities in cassava grown after different cover crops, and the effect of the cover crop on mineral nutrition and cassava yield under an organic farming system. The occurrence and structure […]

Physical Quality of Soils in Agricultural Use in the Semiarid Region of the State of Bahia

Sálvio Napoleão Soares Arcoverde, Alessandra Monteiro Salviano, Nelci Olszevski, Stefeson Bezerra de Melo, Tony Jarbas Ferreira Cunha, Vanderlise Giongo, [...]

01/Sep/2015

ABSTRACT Conversion of a natural condition to agricultural use can impose changes in soil properties and processes and bring environmental consequences to the region this agricultural use encompasses. The aim of this study was to evaluate the physical quality of the soil in agricultural areas of municipalities around Sobradinho Lake, a semiarid region in the State of Bahia, using multivariate analysis statistical techniques as a tool. Initially, descriptive statistical analysis and correlation analysis techniques and the normality test were applied, […]

Chemical and Biochemical Properties of Oxisols after Sewage Sludge Application for 16 Years

Marcela Midori Yada, Wanderley José de Melo, Fábio Luiz Checchio Mingotte, Valéria Peruca de Melo, Gabriel Maurício Peruca de Melo

01/Sep/2015

ABSTRACT The large production of sewage sludge (SS), especially in large urban centers, has led to the suggestion of using this waste as fertilizer in agriculture. The economic viability of this action is great and contributes to improve the environment by cycling the nutrients present in this waste, including high contents of organic matter and plant nutrients. This study evaluated the chemical and biochemical properties of Dystrophic and Eutroferric Latossolos Vermelhos (Oxisols) under corn and after SS application at different […]

Occasional Soil Turnover and Liming in a Clayey Oxisol Under a Consolidated No-tillage System

Jonez Fidalski, Renato Yagi, Cássio Antonio Tormena

01/Sep/2015

ABSTRACT Accumulation of nutrients and surface compaction have been reported after a long time under a no-tillage system. The aim of this study was to evaluate soil chemical properties, bulk density, and crop yield following a single mechanical intervention associated with liming in a clayey Oxisol under a NT system for 17 consecutive years in Pato Branco, southwestern Paraná, Brazil. A randomized block experimental design was used in a split-plot arrangement, with plowing and harrowing of the soil in the […]

Quantitative Assessment of Soil Physical Quality in Northern China Based on S-theory

Dejun Yang, Zhengfu Bian, Kefeng Zhang, Jibing Xiong, Shaogang Lei

01/Sep/2015

ABSTRACT Quantitative assessment of soil physical quality is of great importance for eco-environmental pollution and soil quality studies. In this paper, based on the S-theory, data from 16 collection sites in the Haihe River Basin in northern China were used, and the effects of soil particle size distribution and bulk density on three important indices of the S-theory were investigated on a regional scale. The relationships between unsaturated hydraulic conductivity Ki at the inflection point and S values (S/hi) were […]

Soil Compaction Curve of an Oxisol Under Sugarcane Planted After In-row Deep Tillage

Indiamara Marasca, Stella Vannucci Lemos, Reginaldo Barbosa Silva, Saulo Philipe Sebastião Guerra, Kleber Pereira Lanças

01/Sep/2015

ABSTRACT Soil tillage that maintains the productivity of sugarcane plantations, providing an area for the root development and without traffic on crop rows, has given rise to new technologies in rural areas. The purpose of this study was to evaluate the soil physical properties in two sugarcane plantations, one of which was prepared with deep tilling and the other with conventional tillage. The experiment was conducted in Lençóis Paulista, São Paulo State. Soil penetration resistance and relative density were analyzed. […]

Water Balance Components in Covered and Uncovered Soil Growing Irrigated Muskmelon

Paulo Leonel Libardi, Jaedson Cláudio Anunciato Mota, Raimundo Nonato de Assis, Alexsandro dos Santos Brito, Joaquim Amaro

01/Sep/2015

ABSTRACT Knowledge of the terms (or processes) of the soil water balance equation or simply the components of the soil water balance over the cycle of an agricultural crop is essential for soil and water management. Thus, the aim of this study was to analyze these components in a Cambissolo Háplico (Haplocambids) growing muskmelon (Cucumis melo L.) under drip irrigation, with covered and uncovered soil, in the municipality of Baraúna, State of Rio Grande do Norte, Brazil (05º 04’ 48” […]

Sheep Excreta as Source of Nitrous Oxide in Ryegrass Pasture in Southern Brazil

Michely Tomazi, Emanuelle Cavazini Magiero, Joice Mari Assmann, Tatiane Bagatini, Jeferson Dieckow, Paulo Cesar de Faccio Carvalho, [...]

01/Sep/2015

ABSTRACT Livestock urine and dung are important components of the N cycle in pastures, but little information on its effect on soil nitrous oxide (N2O) emissions is available. We conducted a short-term (39-day) trial to quantify the direct N2O-N emissions from sheep excreta on an experimental area of ryegrass pasture growing on a Typic Paleudult in southern Brazil. Four rates of urine-N (161, 242, 323, and 403 kg ha-1 N) and one of dung-N (13 kg ha-1 N) were applied, […]

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