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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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| Ernani,Paulo Roberto; Rogeri,Douglas Antônio; Proença,Marcelo Machado; Dias,Jaques. |
| The effect of N addition on apple yield and quality may vary according to the tree vigor. Apple trees developed over vigorous rootstocks had shown no response to N application in Brazil. In this study it was evaluated the effect of N addition to the soil on yield and quality of ´Royal Gala´ apples grafted on a dwarf rootstock (M.9). The orchard was planted in 1995 (2,857 trees ha-1) on an Oxisol containing 40 g kg-1 of organic matter and pH 6.0. The experiment was carried out from 1998 up to 2005. Treatments consisted of rates of N (0, 50, 100 and 150 kg ha-1 year-1 from 1998 to 2001, and respectively 0, 100, 200 and 300 kg ha-1 afterwards), all broadcasted within the tree row in two equal splits, at bud break and after harvest, as ammonium sulfate.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Apple yield; M.9 rootstock; Fruit quality; Nitrogen. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452008000400044 |
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