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| Registros recuperados: 67 | |
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| Bortolon,Leandro; Ernani,Paulo Roberto; Bortolon,Elisandra Solange Oliveira; Gianello,Clesio; Almeida,Rodrigo Gabriel Oliveira de; Welter,Samuel; Rogeri,Douglas Antônio. |
| Abstract The objective of this work was to assess the risk of phosphorus losses by runoff through an index based on the degree of P saturation (DPS), in cropland soils of Southern Brazil. Sixty-five highly representative cropland soils from the region were evaluated. Three labile P forms were measured (Mehlich-1, Mehlich-3, and ammonium oxalate), and four P sorption indexes were tested (phosphorus single sorption point and Fe+Al determined with the three extractors). Water-extractable P (WEP) was used as an index of P susceptibility to losses by surface runoff. The DPS was determined from the ratio between labile P and each sorption index. DPS values obtained from the ratio between Mehlich-1 P and the single P sorption point ranged from 1 to 25%, whereas... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eutrophication; Runoff; Single P sorption point; Water quality. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901088 |
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| Matos,A.T.; Pinho,A.P.; Costa,L.M.; Morris,L.A.. |
| Plot-scale overland flow experiments were conducted to evaluate the efficiency of streamside management zones (SMZs) in retaining herbicides in runoff generated from silvicultural activities. Herbicide retention was evaluated for five different slopes (2, 5, 10, 15, and 20%), two cover conditions (undisturbed O horizon and raked surface), and two periods under contrasting soil moisture conditions (summer dry and winter wet season) and correlated to O horizon and site conditions. Picloram (highly soluble in water) and atrazine (moderately sorbed into soil particles) at concentrations in the range of 55 and 35 µg L-1 and kaolin clay (approximately 5 g L-1) were mixed with 13.000 liters of water and dispersed over the top of 5 x 10 m forested plots. Surface... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pollution control; Silviculture; Pesticides; Runoff. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582008000100014 |
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| Ghazalian, Pascal L.; Larue, Bruno; West, Gale E.. |
| This study investigates the determinants affecting producers’ adoption of some Best Management Practices (BMPs). Priors about the signs of certain variables are explicitly accounted for by testing for inequality restrictions through importance sampling. Education, gender, age, and on-farm residence are found to have significant effects on the adoption of some BMPs. Farms with larger animal production are more apt to implement manure management practices, crop rotation, and riparian buffer strips. Also, farms with larger cultivated acres are more inclined to implement herbicide control practices, crop rotation, and riparian buffer strips. Belonging to an agro-environment club has a positive impact for most BMPs. |
| Tipo: Journal Article |
Palavras-chave: Adoption; Bayesian analysis; Best management practices; Priors; Runoff; Water quality; Agribusiness; Agricultural and Food Policy; Crop Production/Industries; Farm Management; Food Consumption/Nutrition/Food Safety; Land Economics/Use; Livestock Production/Industries; Q12; Q25; C11. |
| Ano: 2009 |
URL: http://purl.umn.edu/56655 |
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| Santos,Maria Aparecida do Nascimento dos; Panachuki,Elói; Alves Sobrinho,Teodorico; Oliveira,Paulo Tarso Sanches de; Rodrigues,Dulce Buchala Bicca. |
| Water infiltration in the soil is an important hydrological process that occurs at the interface of the soil-atmosphere system; thus, the soil management practice used has a strong influence on this process. The aim of this study was to evaluate water infiltration in the soil and compare equations for estimating the water infiltration rate in an Ultisol after harvesting common bean (Phaseolus vulgaris L.) under simulated rainfall. Field tests with a rainfall simulator were carried out in three soil management systems: minimum tillage (MT), conventional tillage (CT), and no tillage (NT). In NT, four levels of plant residue on the soil surface were evaluated: 0, 3, 6, and 9 t ha-1. The models of Kostiakov-Lewis, Horton, and Philip were used to estimate the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Runoff; Soil management; Rainfall simulator. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000500026 |
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| Beniaich,Adnane; Silva,Marx Leandro Naves; Guimarães,Danielle Vieira; Bispo,Diêgo Faustolo Alves; Avanzi,Junior Cesar; Curi,Nilton; Pio,Rafael; Dondeyne,Stefaan. |
| ABSTRACT In the tropics, water erosion is one of the most important factors leading to the degradation and deterioration of agricultural land. Olive orchards have a low canopy coverage, especially during the first years after planting, due to the low density of olive trees. Given the fast expansion of olive orchards in Brazil, this study aimed to evaluate the effect of cover vegetation on soil and water losses under natural rainfall. In addition, it was assessed the crop performance and the vegetation cover index in different management systems in olive orchards. The study was carried out in soil erosion plots, where water and sediment were sampled and measured over two crops season, under the following treatments: in the first season, bare soil with olive... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil conservation; Soil loss; Land degradation; Runoff; Olive cultivation. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832020000100503 |
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| Thomaz,Edivaldo Lopes. |
| Gully erosion occurs by the combined action of splash, sheetwash and rill-wash (interrill and rill erosion). These erosion processes have a great capacity for both sediment production and sediment transport. The objectives of this experiment were to evaluate hydrological and sediment transport in a degraded area, severely dissected by gullies; to assess the hydraulic flow characteristics and their aggregate transport capacity; and to measure the initial splash erosion rate. In the study area in Guarapuava, State of Paraná, Brazil (lat 25º 24' S; long 51º24' W; 1034 m asl), the soil was classified as Cambissolo Húmico alumínico, with the following particle-size composition: sand 0.116 kg kg-1; silt 0.180 kg kg-1; and clay 0.704 kg kg-1. The approach of this... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Field measurement; Water erosion; Simulated rain; Rainsplash; Runoff. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100025 |
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| Doblinski,André F.; Sampaio,Silvio C.; Silva,Vanderlei R. da; Nóbrega,Lúcia H. P.; Gomes,Simone D.; Dal Bosco,Tatiane C.. |
| In order to verify the environmental impact of the application of swine farming wastewater in bean crop, an experiment was set up in the Experimental Farm of PUCPR - Toledo, PR, Brazil. Runoff and soil samples were collected at the end of the experiment. Four wastewater treatments were utilized during the experiment (50, 100, 150 and 200 m³ ha-1) and the without wastewater as the control. The results demonstrate that (i) the amounts of potassium, phosphorus, and nitrogen in runoff are exponential, (ii) that phosphorus has a seven-fold polluting potential compared to potassium and three-fold compared to nitrogen, and (iii) that the mobility of potassium in the soil profile is the largest, followed by those of nitrogen and phosphorus. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water reuse; Runoff; Environmental pollution. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010000100012 |
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| Sharpley,Andrew. |
| ABSTRACT Eutrophication of surface waters remains a major use-impairment in many countries, which, in fresh waters, is accelerated by phosphorus (P) inputs from both point (e.g., municipal waste water treatment plants) and nonpoint sources (e.g., urban and agricultural runoff). As point sources tend to be easier to identify and control, greater attention has recently focused on reducing nonpoint sources of P. In Brazil, agricultural productivity has increased tremendously over the last decade as a consequence, to a large extent, of increases in the use of fertilizer and improved land management. For instance, adoption of the “4R” approach (i.e., right rate, right time, right source, and right placement of P) to fertilizer management can decrease P runoff.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertilizer management; Conservation practices; Runoff; Erosion; Eutrophication. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000100001 |
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| Mendes,M.E.G.; Villagra,M.M.; Souza,M.D. de; Bacchi,O.O.S.; Reichardt,K.. |
| Em um estudo das relações hídricas de um seringal de 5 anos de idade, implantado na região sudeste do Brasil em 1984 são mostradas variações de umidade do solo, potencial da água no solo, distribuição radicular, interceptação de precipitação pluvial e escoamento superficial. Resultados indicam a estreita faixa de retenção de água da terra roxa estruturada e a alta correlação entre as variações de potencial da água no solo e a distribuição radicular. O seringal apresentou um sistema radicular com raízes superficiais (0-30cm) se estendendo até a projeção das copas e raízes profundas, atingindo mais de 2,5m. O perfil de solo não apresentou escoamento subsuperficial de água ao longo do declive de 10%, mas apresentou significantes perdas superficiais, chegando... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Seringueira; Distribuição radicular; Umidade do solo; Potencial da água no solo; Runoff; Interceptação de chuva. |
| Ano: 1992 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161992000400014 |
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| Bertol,Ildegardis; Guadagnin,Jean Cláudio; González,Antonio Paz; Amaral,André Júlio do; Brignoni,Leonardo Felipe. |
| Soil tillage influences water erosion, and consequently, losses of calcium, magnesium and organic carbon in surface runoff. Nutrients and organic carbon are transported by surface runoff in particulate form, adsorbed to soil colloids or soluble in water, depending on the soil tillage system. This study was carried out on an Inceptisol, representative of the Santa Catarina highlands, southern Brazil, between November 1999 and October 2001, under natural rainfall. The soil tillage treatments (no replications) were: no-tillage (NT), minimum soil tillage with chiseling + disking (MT), and conventional soil tillage with plowing + two diskings (CT). The crop cycles sequence was soybean (Glycine max), oats (Avena sativa), beans (Phaseolus vulgaris) and vetch... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Runoff; Sediment; Nutrient in runoff; Nutrient in sediments; Nutrient losses. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000600011 |
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| Registros recuperados: 67 | |
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