Rusle parameters for modeling the loss of a soil subjected to pig slurry application

O objetivo deste trabalho foi determinar parâmetros de ajuste para a equação universal de perda de solo revisada (Rusle) de um solo submetido à aplicação de dejeto líquido de suínos. Os tratamentos consistiram de 0, 50, 100 e 200 m3 ha-1 de dejeto líquido de suínos (DLS), após o cultivo de aveia-preta (Avena strigosa), além da aplicação de 50 m3 ha-1 de DLS por seis vezes à superfície do solo, em uma sequência temporal, e de um controle com solo sem cultivo e sem dejeto. As avaliações foram feitas quanto à massa de matéria seca da parte aérea da aveia-preta, à massa de raízes e aos resíduos da cultura semi-incorporados ao solo, às perdas de solo por meio de chuva simulada e aos parâmetros para modelagem de erosão hídrica. A aplicação de dejeto líquido de suínos à superfície do solo causou a diminuição dos valores de consolidação do solo (Cf), o aumento da massa de raízes vivas e mortas e dos resíduos culturais incorporados à camada superficial (0.0–0.1 m) do solo (Bu), e a redução dos valores de uso anterior da terra (PLU) na Rusle.The objective of this work was to determine adjustment parameters for the revised universal soil loss equation (Rusle) of a soil subjected to pig slurry application. Treatments consisted of 0, 50, 100, and 200 m3 ha-1 pig slurry (PS), after the cultivation of black oat (Avena strigosa), besides the application of 50 m3 ha-1 PS for six times onto the soil surface in a temporal sequence, and a control treatment of soil without cultivation and without pig slurry application. The evaluations were performed for black oat shoot dry mass, root mass and crop residues semi-incorporated into the soil (RMR), soil losses by means of simulated rain, and the parameters for water erosion modeling. The pig slurry application onto soil surface caused a reduction in the values of the soil consolidation parameter (Cf), an increase in the mass of living and dead roots and cultural residues incorporated in the upper layer (0.0–0.1 m) of the soil (Bu), and a reduction in the subfactor prior land use (PLU) of the Rusle

Transport of sediments, carbon and nutrients in areas of reforestation and grassland based on simulated rainfall

The objective of this study was to evaluate the soil losses, as well as carbon and chemical samples in runoff through areas of pine (Pinus taeda), eucalyptus (Eucalyptus dunni) and a consortium of pasture with oat (Avena stringosa) and ryegrass (Lolium multiflorium) in the Fragosos river basin, in Concordia, SC. For this, rainfall simulations with mean intensities of 94 mm h-1 were conducted in September and November 2011, in plots of 1 m2 established in the three areas. Runoff, loads carried of the sediment, and carbon and chemical concentrations were quantified in the experiment. The results showed that the concentrations of sediment and organic carbon were higher in the eucalyptus area. The largest concentrations of chemicals for all areas were nitrate, calcium, magnesium and potassium. Total carbon, organic carbon, sediment and nitrate were transported in higher loads in the eucalyptus area. With the exception of nitrate and chloride, the chemical loads carried were higher in the pasture area

Concentrações e cargas de nitrato e fosfato na Bacia do Ribeirão Concórdia, Lontras, SC Concentrations and loads of nitrate and phosphate in the Ribeirão Concórdia river basin, Lontras, SC

Neste trabalho foram determinadas as concentrações e as cargas de nitrato e de fosfato inorgânico total, na água de escoamento superficial, de drenagem e subterrânea, na bacia do Ribeirão Concórdia, Lontras, SC. Foram coletadas 102 amostras durante 109 dias, em três seções fluviométricas, três lisímetros e três poços piezométricos, distribuídos no interior da bacia. As concentrações foram comparadas com os padrões estabelecidos nas Resoluções CONAMA no. 357/2005 e no. 420/2009. As concentrações de nitrato e de fosfato no escoamento e drenagem dos lisímetros foram maiores que aquelas das seções fluviométricas e dos poços piezométricas. Nas seções fluviométricas e no escoamento superficial do lisímetro com pastagem as concentrações de nitrato foram inferiores aos padrões estabelecidos para essas águas. As concentrações de fosfato nas seções fluviométricas e nos lisímetros tanto do escoamento superficial quanto da drenagem e nos piezômetros, superaram os padrões das Resoluções CONAMA no. 357/2005 e no. 420/2009. As águas de drenagem nos lisímetros transportaram cargas de nitrato e de fosfato superiores àquelas do escoamento superficial; estas, por sua vez, transportaram cargas similares às dos rios.<br>This study presents concentrations and loads of nitrate and total inorganic phosphate in surface runoff infiltrating water and subsurface flow in the basin of Ribeirao Concordia, Lontras, SC - Brazil . Over a 109-day period, 102 samples were collected from three river sections, three lysimeters and three piezometric wells in the interior of the basin. Concentrations were compared with the standards given in the CONAMA Resolutions 357/2005 and 420/2009. Concentrations of nitrate and phosphate in lysimeter drainage water and flows were greater than those in river sections and piezometric wells. In the river sections and in surface flow from the lysimeter under pasture, nitrate concentrations were lower than the benchmarks set for such waters. Phosphate concentrations in the river sections and in both lysimeter surface runoff and in drainage water, and in the piezometers, all exceeded the standards defined in CONAMA Resolutions 357/2005 and 420/2009. Drainage waters in the lysimeters transported nitrate and phosphate loads greater than those in surface runoff, which in turn transported loads of the same order of magnitude as in river flow

Impacts of Pig Slurry Applied to Two Different Soils on Nutrient Transport by Runoff

ABSTRACT: Runoff in agricultural areas with intensive application of pig slurry can transport significant amounts of nutrients. This study evaluates the effects of different pig slurry (PS) application rates (0, 50, 100, and 200 m3 ha-1) on nutrient loss through runoff during soybean cultivation under no-tillage. It was conducted at two sites in southern Brazil, one on an Alfisol (27° 43' south and 50° 3' west) and one on an Inceptisol (27° 47' south and 50° 18' west). The PS was applied to the soil once at the beginning of the soybean cycle. Each plot was 11 m long in the direction of the slope and 3.5 m wide. To induce runoff, artificial rainfall was applied in four different tests (T1, T2, T3, T4), with an intensity of 65 mm h-1 for 90 minutes. The first test was performed one day after PS application, while the other tests were performed throughout the soybean cycle. During each test, runoff samples were collected at 10-min intervals after the beginning of runoff. The runoff amount and the NO3-, NH4+, P, and K+ concentrations in the runoff were measured. In T1, nutrient transport from the Alfisol and the Inceptisol increased with increasing PS doses. In some cases, this effect was still noticeable in T2 and T3, but not in the last test (T4). The transported amounts of NO3-, NH4+, P, and K+ decreased as the period between PS application and simulated rainfall increased. Regardless of the soil and the treatment, NO3- was transported in the greatest quantities, followed by K+, NH4+, and P