Acúmulo de formas de fósforo em um argissolo com histórico de aplicações de dejetos suínos

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Agroecossistemas, Florianópolis, 2011As sucessivas aplicações de dejetos de suínos ao longo dos anos podem provocar o acúmulo de fósforo (P) no solo e alterar as suas formas. O objetivo do presente trabalho foi avaliar o potencial contaminante do P em um Argissolo Vermelho Amarelo submetido a aplicações sucessivas de dejetos líquidos e cama sobreposta de suínos sob sistema de plantio direto. Em janeiro de 2003 foi estabelecido um experimento no município de Braço do Norte (SC), onde os tratamentos foram testemunha, dejetos líquidos de suínos, equivalente à recomendação de N ha-1 ano-1 e ao dobro da recomendação (DLS1 e DLS2), cama sobreposta de suínos, equivalente à recomendação de N ha-1 ano-1 e ao dobro da recomendação (CS1 e CS2) para a sucessão milho e aveia. Em março de 2010 foi aberta uma trincheira no centro de cada parcela onde se coletou solo nas camadas de 0-2,5; 2,5-5; 5-10; 10-15; 15-20 e 20-30 cm, que foi submetido ao fracionamento químico de P proposto por Hedley. No solo das camadas de 0-2,5 e 20-30 cm dos tratamentos testemunha, DLS1 e CS1 foi determinada a capacidade máxima de adsorção de P (CMAP). Aplicações sucessivas de dejetos líquidos de suínos e cama sobreposta, na superfície do solo manejado sob SPD, incrementaram os teores de P inorgânico e orgânico no perfil do solo, especialmente nas formas inorgânicas lábeis. A aplicação de CS1 na superfície do solo provocou diminuição dos valores de CMAP no solo da camada mais profunda, 20-30 cm, indicando a saturação de parte dos sítios de adsorção das partículas. As sucessivas aplicações de dejetos de suínos no solo ao longo de 88 meses propiciaram o acúmulo de fósforo em formas predominantemente lábeis no solo, representando risco de contaminação ambiental de águas superficiais e subsuperficiais.Successive applications of pig slurry and deep litter over the years can cause the accumulation of various forms of phosphorus (P) in the soil. The aim of this study was to evaluate the accumulation of soil P in an Hapludalf subjected to successive applications of slurry and deep litter under no-tillage system. In January 2003 an experiment was established in the city of Braço do Norte (SC) where treatments were control, pig slurry at the recommended nitrogen rate (DLS1), pig slurry at twice the recommended rate (DLS2) deep litter, equivalent to the recommended nitrogen rate (CS1) and deep litter, equivalent to twice the recommended rate (CS2) for the cultivation of maize and oats. From 2003 to 2010 Zea mays and Avena strigosa, were grown in succession, under no-tillage. In March 2010, after 88 months a trench was opened in the center of each plot to sample soil layers of 0-2.5, 2.5-5; 50-10, 10-15, 15-20 and 20-30 cm. The P forms were determined by chemical fractionation of Hedley. The control treatment, DLS1 and CS1 were tested for maximum P adsorption (CMAP). The results showed that successive applications of liquid manure and deep litter increased the levels of phosphorus to 30 cm depth, especially in labile inorganic forms extracted by anion exchange resin, NaHCO3 0.5 mol L-1, NaOH 0,1 mol L-1. The application of CS1 on the soil surface caused the lowest values of CMAP in the deeper layer of soil, 20-30 cm, indicating the saturation of the adsorption sites of the particles. Successive applications of pig slurry and pig litter in the soil over 8 years increased the accumulation of predominantly labile phosphorus forms in the soil, representing a risk of environmental contamination of surface and subsurface

Phosphorus fractions in sandy soils of vineyards in southern Brazil

Phosphorus (P) applications to vineyards can cause P accumulation in the soil and maximize pollution risks. This study was carried out to quantify the accumulation of P fractions in sandy soils of vineyards in southern Brazil. Soil samples (layers 0-5, 6-10 and 11-20 cm) were collected from a native grassland area and two vineyards, after 14 years (vineyard 1) and 30 years (vineyard 2) of cultivation, in Santana do Livramento, southern Brazil, and subjected to chemical fractionation of P. Phosphorus application, especially to the 30-year-old vineyard 2, increased the inorganic P content down to a depth of 20 cm, mainly in the labile fractions extracted by anion-exchange resin and NaHCO3, in the moderately labile fraction extracted by 0.1 and 0.5 mol L-1 NaOH, and in the non-labile fraction extracted by 1 mol L-1 HCl, indicating the possibility of water eutrophication. Phosphorus application and grapevine cultivation time increased the P content in the organic fraction extracted by NaHCO3 from the 0-5 cm layer, and especially in the moderately labile fraction extracted by 0.1 mol L-1 NaOH, down to a depth of 20 cm

Phosphorus fractions in sandy soils of vineyards in southern Brazil Frações de fósforo em solos arenosos cultivados com videira na região sul do Brasil

Phosphorus (P) applications to vineyards can cause P accumulation in the soil and maximize pollution risks. This study was carried out to quantify the accumulation of P fractions in sandy soils of vineyards in southern Brazil. Soil samples (layers 0-5, 6-10 and 11-20 cm) were collected from a native grassland area and two vineyards, after 14 years (vineyard 1) and 30 years (vineyard 2) of cultivation, in Santana do Livramento, southern Brazil, and subjected to chemical fractionation of P. Phosphorus application, especially to the 30-year-old vineyard 2, increased the inorganic P content down to a depth of 20 cm, mainly in the labile fractions extracted by anion-exchange resin and NaHCO3, in the moderately labile fraction extracted by 0.1 and 0.5 mol L-1 NaOH, and in the non-labile fraction extracted by 1 mol L-1 HCl, indicating the possibility of water eutrophication. Phosphorus application and grapevine cultivation time increased the P content in the organic fraction extracted by NaHCO3 from the 0-5 cm layer, and especially in the moderately labile fraction extracted by 0.1 mol L-1 NaOH, down to a depth of 20 cm.<br>As aplicações de fósforo (P) em vinhedos podem causar o acúmulo desse nutriente no solo e maximizar seu potencial poluente. Este trabalho objetivou quantificar as frações de acumulação de P em solos arenosos cultivados com videiras na região Sul do Brasil. Para isso, amostras de solo foram coletadas nas camadas de 0-5, 6-10 e 11-20 cm em uma área de campo nativo e em dois vinhedos: um com 14 anos de cultivo (vinhedo 1) e outro com 30 anos (vinhedo 2), localizados no município de Santana do Livramento, Rio Grande do Sul (RS), Brasil. As amostras foram secas, moídas e submetidas ao fracionamento químico de P. Os resultados evidenciaram que os teores de P inorgânico aumentaram até 20 cm de profundidade, principalmente no vinhedo 2, em especial nas frações lábeis extraídas por resina de troca aniônica e por NaHCO3, na fração moderadamente lábil, extraída por NaOH 0,1 e 0,5 mol L-1, e na fração não lábil, extraída por HCl 1 mol L-1, representando potencial de eutroficação das águas. As aplicações de fertilizantes fosfatados na adubação de correção e de manutenção nos vinhedos com maior tempo de cultivo aumentaram os teores de P na fração orgânica extraída por NaHCO3 na camada de 0-5 cm, e na fração moderadamente lábil extraída por NaOH 0,1 mol L-1, até 20 cm de profundidade

Phosphorus accumulation and pollution potential in a hapludult fertilized with pig manure

Successive applications of pig litter to the soil surface can increase the phosphorus (P) content and alter its adsorption, promoting P transfer to surface or subsurface waters. The purpose of this study was to evaluate P accumulation and the pollution potential of a soil after application of pig litter. In March 2010, eight years after the installation of an experiment in Braço do Norte, Santa Catarina, SC, Brazil, on a Typic Hapludult, soil was sampled (layers 0-2.5, 2.5-5, 5-10, 10-15, 15-20 and 20-30 cm) after the following fertilization treatments: no pig litter fertilization, pig slurry application and pig manure application. In this period, 694 and 1,890 kg P2O5 ha-1 were applied in the treatments with pig slurry and pig manure, respectively. The P content was determined, based on Mehlich-1, anion exchange resin (AER), 0.01 mol L-1 CaCl2 and total P in the samples. The adsorption isotherm parameters were also determined by the Langmuir and Koski-Vähälä &amp; Hartikainem models in the layers 0-2.5 and 20-30 cm. The application of 1,890 kg P2O5 ha-1 in the form of pig manure led to P accumulation, as evidenced by Mehlich-1, down to a depth of 15 cm, by AER and 0.01 mol L-1 CaCl2 down to 20 cm and by total P to 30 cm. After application of 1,890 kg P2O5 ha-1 in the form of pig manure, the values of maximum P adsorption capacity were lowest in the deepest layer (20-30 cm), indicating the occupation of part of the adsorption sites of the particles. The application of swine manure to the soil over eight years increased the P quantity in the soil solution of the surface layer, indicating environmental contamination risk for surface and subsurface waters

Changes in soil acidity and organic carbon in a sandy typic hapludalf after medium-term pig-slurry and deep-litter application

Successive applications of liquid swine waste to the soil can increase the contents of total organic carbon and nutrients and change acidity-related soil chemical properties. However, little information is available on the effects of swine waste application in solid form, as of swine deep-litter. The objective of this study was to evaluate alterations of organic carbon and acidity-related properties of a soil after eight years of pig slurry and deep-litter application. In the eighth year of a field experiment established in Braço do Norte, Santa Catarina (SC) on a sandy Typic Hapludalf samples were taken (layers 0-2.5; 2.5-5; 5-10; 10-15; 15-20 and 20-30 cm) from unfertilized plots and plots with pig slurry or deep-litter applications, providing the simple or double rate of N requirement of Zea mays and Avena strigosa in rotation. Soil total organic carbon, water pH, exchangeable Al, Ca and Mg, and cation exchange capacity (CECeffective and CECpH7.0), H+Al, base saturation, and aluminum saturation were measured. The application of pig slurry and deep-litter for eight years increased total organic carbon and CEC in all soil layers. The pig slurry and deep-litter applications reduced active acidity and aluminum saturation and increased base saturation down to a depth of 30 cm. Eight years of pig slurry application did not affect soil acidity