146 results

Relationships between Agriculture, Riparian Vegetation, and Surface Water Quality in Watersheds

Tiago Broetto, Carlos Gustavo Tornquist, Ben-Hur Costa de Campos, Júlio Cézar Schneider

21/Mar/2017

ABSTRACT Agricultural land use and degradation of natural vegetation in riparian zones can impair water quality. This study was conducted in seven agricultural watersheds in Ibirubá, RS, Brazil, with the following objectives: identify relationships between concentrations of soluble phosphorus (Psol) and nitrate (NO−3) in surface water and agricultural use of soil and current vegetation in riparian zones, and assess the risk of eutrophication. Water samples from the main watercourses in each watershed were collected monthly from 10/2013 to 6/2014. Current […]

Soil Organic Matter Quality in Jatropha spp. Plantations in Different Edaphoclimatic Conditions

Rita de Cássia Alves de Freitas, Gustavo Vicentini Popin, Débora Marcondes Bastos Pereira Milori, Diana Signor, Marcos Antônio Drumond, Carlos Eduardo Pellegrino Cerri

09/Mar/2017

ABSTRACT The substitution of native vegetation by agricultural ecosystems can change the quantity and quality of soil organic matter (SOM), and the intensity of these changes depends on the soil type, climate, and land use. The objective of this study was to evaluate the quality of organic matter in chronosequences of Jatropha cultivation in contrasting soil and climatic conditions. Soil samples were evaluated at depths of 0.00-0.10, 0.20-0.30, and 0.80-1.00 m in chronosequences located in Planaltina, Distrito Federal (Cerrado-Pasture-Jatropha), Dourados, […]

Physical Properties and Crop Management for Corn in an Albaqualf

Robson Giacomeli, Enio Marchesan, Maurício Limberger de Oliveira, Thomas Newton Martin, Gustavo Mack Teló, Gabriel Donato, [...]

09/Mar/2017

ABSTRACT Rice monoculture in lowlands can cause problems for management practices in crop fields, for example, in weed control. For this reason, corn in rotation with irrigated rice in lowlands may be advantageous, despite problems with soil compaction and water excess. The objective of this study was to evaluate soil physical properties and corn performance in soil management systems in an Albaqualf soil (lowlands). Two experiments were conducted in the field, in the 2013/14 and 2014/15 crop seasons. The experimental […]

Water Erosion in Different Slope Lengths on Bare Soil

Bárbara Bagio, Ildegardis Bertol, Neuro Hilton Wolschick, Danieli Schneiders, Maria Aparecida do Nascimento dos Santos

20/Feb/2017

ABSTRACT Water erosion degrades the soil and contaminates the environment, and one influential factor on erosion is slope length. The aim of this study was to quantify losses of soil (SL) and water (WL) in a Humic Cambisol in a field experiment under natural rainfall conditions from July 4, 2014 to June 18, 2015 in individual events of 41 erosive rains in the Southern Plateau of Santa Catarina and to estimate soil losses through the USLE and RUSLE models. The […]

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

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

20/Feb/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/Dec/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/Dec/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/Oct/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/Oct/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/Aug/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 […]

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