132 results

Nutrient and Organic Carbon Losses, Enrichment Rate, and Cost of Water Erosion

Ildegardis Bertol, Rodrigo Vieira Luciano, Camilo Bertol, Bárbara Bagio

20/fev/2017

ABSTRACT Soil erosion from water causes loss of nutrients and organic carbon, enriches the environment outside the erosion site, and results in costs. The no-tillage system generates increased nutrient and C content in the topsoil and, although it controls erosion, it can produce a more enriched runoff than in the conventional tillage system. This study was conducted in a Humic Cambisol in natural rainfall from 1997 to 2012 to quantify the contents and total losses of nutrients and organic C […]

Diagnosis of the Accelerated Soil Erosion in São Paulo State (Brazil) by the Soil Lifetime Index Methodology

Grasiela de Oliveira Rodrigues Medeiros, Angelica Giarolla, Gilvan Sampaio, Mara de Andrade Marinho

12/dez/2016

ABSTRACT: The soil is a key component of the Earth System, and is currently under high pressure, due to the increasing global demands for food, energy and fiber. Moreover, the management of agricultural systems is often inadequate and ignores the agricultural suitability of lands, and particularly the vulnerability of soils. This paper demonstrates the application of the concept of the Soil Lifetime Index (SLtI) for the entire state of São Paulo, at a spatial resolution of 30 m. The SLtI […]

Estimates of Annual Soil Loss Rates in the State of São Paulo, Brazil

Grasiela de Oliveira Rodrigues Medeiros, Angelica Giarolla, Gilvan Sampaio, Mara de Andrade Marinho

12/dez/2016

ABSTRACT: Soil is a natural resource that has been affected by human pressures beyond its renewal capacity. For this reason, large agricultural areas that were productive have been abandoned due to soil degradation, mainly caused by the erosion process. The objective of this study was to apply the Universal Soil Loss Equation to generate more recent estimates of soil loss rates for the state of São Paulo using a database with information from medium resolution (30 m). The results showed […]

Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems

Romeu de Souza Werner, Fabrício Tondello Barbosa, Ildegardis Bertol, Neuro Hilton Wolshick, Kristiana Fiorentin dos Santos, Josie Moraes Mota

05/out/2016

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 […]

Soybean Tillage Systems and Physical Changes in Surface Layers of Two Albaqualf Soils

Gerson Meneghetti Sarzi Sartori, Enio Marchesan, Ricardo De David, Reimar Carlesso, Mirta Teresinha Petry, Núbia Pentiado Aires, [...]

05/out/2016

ABSTRACT A compacted subsurface soil layer can be a limiting factor for soybean growing, reducing soybean yield. The aim of this study was to evaluate the effect of different tillage systems on the physical properties of two Albaqualf soils of the Central Plains region in the state of Rio Grande do Sul in southern Brazil. Two experiments were conducted: one in Santa Maria, RS, during the 2013/14 and 2014/15 crop seasons, and another in Formigueiro, RS, during the 2013/14 crop […]

Successive Cultivation of Soybean/Corn Intercropped with Urochloa brizantha topdressed with Nitrogen

Danilo Gomes Fortes, Edgard Jardim Rosa, Yara Brito Chaim Jardim Rosa, Fábio Régis de Souza, Evandro Gelain

23/ago/2016

ABSTRACT Corn intercropped with Urochloa brizantha (Syn, Brachiaria brizantha) has been indicated as a suitable alternative management practice for rational land use in crop-livestock production systems in the Cerrado region of Brazil. An experiment was carried out in Maracaju, MS, Brazil to evaluate the effect of sequences of soybean/second-crop corn systems intercropped with Urochloa brizantha and the effects of forms of nitrogen on soil chemical and physical properties. A randomized block experimental design was used with four replications; treatments were […]

Hydrophysical Quality of an Oxisol and Sugarcane Yield in Chisel Plow-Based Sugarcane Ratoon Management

Marcos Vinicius Garbiate, Antonio Carlos Tadeu Vitorino, Eber Augusto Ferreira do Prado, Munir Mauadand, Douglas Martins Pereira Pellin

28/jun/2016

ABSTRACT Mechanical harvesting has increasingly been used in sugarcane production units, and it has often resulted in reduced structural quality of the soil due to soil compaction caused by machine traffic. Thus, sugarcane ratoon crops have often been chiseled to overcome such a problem. The aim of the current study is to assess some physical properties of a Latossolo Vermelho Distroférrico (Rhodic Hapludox) that was chiseled after the third harvest in a sugarcane ratoon crop. The study was conducted in […]

Spatial and Temporal Variability of Soil CO2 Flux in Sugarcane Green Harvest Systems

Rose Luiza Moraes Tavares, Zigomar Menezes de Souza, Newton La Scala, Guilherme Adalberto Ferreira Castioni, Gustavo Soares de Souza, José Luiz Rodrigues Torres

06/jun/2016

ABSTRACT The sugarcane green harvest system, characterized by mechanized harvesting and the absence of crop burning, affects soil quality by increasing crop residue on the soil surface after harvest; thus, it contributes to improving the physical, chemical, and microbiological properties and influences the soil carbon content and CO2 flux (FCO2). This study aimed to evaluate the spatial and temporal variability of soil FCO2 in sugarcane green harvest systems. The experiment was conducted in two areas of sugarcane in São Paulo, […]

Changes in Soil Organic Carbon and Nitrogen Stocks in Long-Term Experiments in Southern Brazil Simulated with Century 4.5

Mirla Andrade Weber, João Mielniczukand, Carlos Gustavo Tornquist

12/maio/2016

ABSTRACT The Century model has successfully simulated soil organic matter dynamics in many agroecosystems. However, initial applications in southern Brazil produced mixed results. The objective of this study was to calibrate and validate Century 4.5 to simulate soil carbon (C) and nitrogen (N) dynamics under diverse soil management practices in subtropical Brazil. Soil C and N data from two long-term experiments established on a degraded Acrisol in the early 1980s were used. Treatments were conventional or no-tillage; grass or grass/legume […]

Autumn Maize Intercropped with Tropical Forages: Crop Residues, Nutrient Cycling, Subsequent Soybean and Soil Quality

Francisco Cézar Belchor Lages Pereira, Luiz Malcolm Mano de Mello, Cristiano Magalhães Pariz, Veridiana Zocoler de Mendonça, Élcio Hiroyoshi Yano, Elka Elice Vasco de Miranda, [...]

12/maio/2016

ABSTRACT Autumn maize intercropped with tropical forages can raise the amount of crop residues and improve nutrient cycling, favoring subsequent soybean crop. The objective of this study was to evaluate the effect of forms of implementation of intercropping of irrigated autumn maize with tropical forages on yield, decomposition, nutrient accumulation and release, and on the ratio of lignin/total N of forage residues, yield components, and grain yield of subsequent soybean, and on soil physical and chemical properties, under no-tillage in […]

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