Erosão hídrica em um Cambissolo Háplico após aplicação de dejeto líquido de suínos

Water (WL), soil (SL), phosphorus (P) and potassium (K) losses by water erosion and subsurface flow are influenced by soil management and by soil fertilization with swine slurry (SS). The study was conducted between 09/2014 and 11/2015, in a Haplic Dystrudept, to evaluate the 0 (zero), 50, 100 and 200 m³ ha-1 SS doses applied to millet (Pennisetum americanum), black oats (Avena strigosa) and crotalaria (Crotalaria ochroleuca), compared with a soil without cultivation and without SS. The soil total porosity (Tp) and macroporosity (Ma), the P and K concentration in the soil, in the runoff, and in the subsurface flow, the dry mass of the aerial part (DM) of crops, and the WL and SL were determined. The main results show the application of SS in the soil results in an increase in Tp and Ma, as well as in the concentration of P and K in the soil and the DM of the plants, in relation to the absence of SS. Water erosion decreases with an increased dose of SS applied to the soil in the interval between 50 and 200 m3 ha-1. The increase in the dose of SS increases the concentration and total losses of P and K in the runoff and decreases the concentration of these nutrients in the subsurface flow in the interval between 50 and 200 m3 ha-1. The increase of DM of the plants, in the interval between 13.75 and 22.82 t ha-1, decreases SL at an average rate of 2.90 t ha-1. The concentration of K in the subsurface flow water was negatively related to the concentration of the element in the subsurface flow.As perdas de água, solo, fósforo (P) e potássio (K) por erosão hídrica e escoamento subsuperficial são influenciadas pelo manejo e fertilização do solo com dejeto líquido de suínos (DLS). A pesquisa foi conduzida em 09/2014 e 11/2015, em um Cambissolo Háplico, para avaliar as doses 0 (zero), 50, 100 e 200 m³ ha-1 de DLS aplicado no milheto (Pennisetum americanum), aveia preta (Avena strigosa) e crotalária (Crotalaria ochroleuca), em comparação ao solo sem cultivo e sem DLS. A porosidade total (PT) e macroporosidade (Ma) do solo, as concentrações de P e K no solo, na enxurrada e no escoamento subsuperficial, a massa seca da parte aérea das culturas (MS), e as PA e PS pela foram determinadas. Os principais resultados mostram que a aplicação de DLS no solo resulta em aumento da PT e Ma e da concentração de P e K no solo, além da MS das plantas, em relação à ausência de dejeto. A erosão hídrica diminui com o aumento da dose de DLS, no intervalo entre 50 e 200 m3 ha-1 do dejeto aplicado no solo em relação à dose de 50. O aumento da dose de DLS faz aumentar a concentração e as perdas totais de P e K no escoamento superficial e diminuir a concentração desses nutrientes no fluxo subsuperficial, no intervalo entre 50 e 200 m3 ha-1 de dejeto. O aumento de MS das plantas, no intervalo entre 13,75 e 22,82 t ha-1, faz diminuir as PS a uma taxa média de 2,90 t ha-1. A concentração de K na água do fluxo subsuperficial se relaciona negativamente com a concentração do elemento no escoamento superficial

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

Impacto da antropização na qualidade da água e no solo de áreas ciliares avaliado em uma bacia hidrográfica na região Sul do Brasil

The anthropization of terrestrial environments has increased the production and concentration of nutrients and organic compounds in shallow bodies of water and in the soil along river banks, thereby causing changes in both water and soil quality. To examine the impact of anthropization on river environments, the phosphorus, potassium, and carbon content in the water and the phosphorus, potassium, and organic matter in the soil were analyzed at eighteen sites. The experimental area is located in an urbanized drainage basin located in the municipality of Lages, Santa Catarina (southern Brazil). The water samples were collected in two field surveys. The first one occurred between August and December 2016, and the second took place from March to June 2017. The soil samples were collected in one field survey from August 2016 and June 2017. The 18 sites were regularly distributed across forests, native grasslands, and urban areas. The dissolved phosphorus and potassium in the water were obtained by applying the methodology proposed by MURPHY & RILEY (1962), whereas the dissolved carbon in the water was mineralized by combustion using an oven at 800 ºC and calculated with the Analytik Jena Multi N/C 2100 TOC/TN Analyzer. On the other hand, the extractable phosphorus and potassium from the soil and organic matter were determined with the methodology described by TEDESCO et al. (1995). The results demonstrated that the concentration of dissolved phosphorus, potassium, and carbon in the water was greater in the parts of the river that cross through urban areas than in the parts of the river that course through grasslands and forests throughout practically the entire year. The same trend was observed with the phosphorus and potassium content in the soil along the river banks. However, the organic matter content in the soil was lower in the sections located in urban areas. The findings indicate that in urban areas where sewage treatment is either nonexistent or deficient, the release of domestic wastewater containing household detergents and soaps contributes to the increase in the content of phosphorus, potassium, and carbon in the water and phosphorus and potassium in the soil.A antropização de ambientes terrestres tem aumentado a produção de nutrientes e de compostos orgânicos e o aporte dos mesmos nas águas superficiais e no solo localizado nas margens das mesmas, ocasionado alterações na qualidade da água e do solo. Com o objetivo de avaliar o impacto da antropização no ambiente ciliar, foi realizada análise de fósforo, potássio e carbono na água, bem como de fósforo, potássio e matéria orgânica no solo, em 18 locais, respectivamente, na água do Ribeirão Petrópolis e no solo às suas margens, numa bacia hidrográfica na cidade de Lages, SC, Brasil. As coletas de amostras de água foram realizadas em agosto e dezembro de 2016, e em março e junho de 2017. As coletas de amostras de solo ocorreram apenas em agosto de 2016 e junho de 2017. Os locais amostrados situavam-se em áreas de floresta, campo nativo e área urbana. O fósforo e potássio dissolvido na água foram determinados conforme metodologia descrita por MURPHY & RILEY (1962), enquanto o carbono dissolvido em água foi mineralizado por combustão em forno a 800 ºC e determinado em TOC/TN Analytik Jena Multi N/C 2100. Já fósforo e potássio extraível do solo e matéria orgânica foram determinados conforme medologias descritas em TEDESCO et al. (1995). Observou-se que a concentração de fósforo, potássio e carbono dissolvido na água foi maior no trecho do rio que passava pela área urbana do que naquele que passava pelo campo e pela floresta, em praticamente todas as épocas do ano. O mesmo comportamento ocorreu com o fósforo e potássio no solo às margens do rio. Entretanto, o teor de matéria orgânica no solo foi menor no trecho que passava pela área da cidade. Os resultados dessa pesquisa apontaram que na área urbana, onde o tratamento de esgoto não era realizado, ou era deficitário, o lançamento de efluentes domésticos contendo detergentes fosfatados e sabões acarretaram no aumento do fósforo, potássio e carbono na água e de fósforo e potássio no solo

Cobertura do solo, produção de biomassa e acúmulo de nutrientes por plantas de cobertura

The use of cover crops is an important strategy for maintaining the productive capacity of agricultural land. This research aimed to determine the soil coverage, biomass production and accumulation of N, P, K, Ca and Mg in plant tissue of different species of cover crops on the southern plateau of Santa Catarina, Brazil. The experiment was conducted in a Humic Cambisol (Inceptisol) with the following treatments: i) BO - black oat (Avena strigosa); ii) WR - wild radish (Raphanus sativus L.); iii) CV - common vetch (Vicia sativa); iv) IS - intercropping of the three species; and v) WF - winter fallow with spontaneous vegetation. The use of cover crops has potential for high biomass production, canopy cover and nutrient accumulation by plant tissue, higher than winter fallow. In the early stage of plant development the highest growth rates and soil coverage occur in WR and IS, while at the end are higher in CV and IS. The crops of BO, CV and IS produce large amounts of dry shoot mass and BO produces greater dry root mass. In general, the CV and IS treatments and the shoot accumulate greater amounts of nutrients in plant tissue as compared to other treatments and the roots, respectively.A utilização de plantas de cobertura do solo é importante estratégia para manutenção da capacidade produtiva de áreas agrícolas. A pesquisa objetivou determinar a cobertura do solo, a produção de fitomassa e o acúmulo de N, P, K, Ca e Mg no tecido vegetal de diferentes espécies de plantas de cobertura no Planalto Sul Catarinense. O experimento foi conduzido em um Cambissolo Húmico e foram avaliados os tratamentos: i) AP - aveia preta (Avena strigosa); ii) NF - nabo forrageiro (Raphanus sativus L.); iii) EC - ervilhaca comum (Vicia sativa); iv) CE - consórcio das três espécies; e v) PO - pousio com vegetação espontânea. O uso de plantas de cobertura tem potencial para alta produção de biomassa, cobertura pelo dossel e acúmulo de nutrientes pelo tecido vegetal, superior ao pousio de inverno. No início do desenvolvimento vegetal maior taxa de crescimento e cobertura do solo ocorrem em NF e CE, enquanto ao final destacam-se EC e CE. Os cultivos de AP, EC e CE produzem maiores quantidades de massa seca de parte aérea e o de AP produz maior massa de raízes. No geral, os tratamentos EC e CE e a parte aérea das plantas acumulam mais nutrientes no tecido vegetal em comparação aos demais tratamentos e as raízes, respectivamente

Erosion under different slope lengths in bare soil

The water erosion degraded the soil and contaminates the environment, influenced, among other factors, the slope length. This work aimed to quantify the losses of soil (PS) and water (PA) in different slope lengths in Cambissolo Húmico soil, in a field experiment in natural rainfall condition in Lages, SC and estimate losses soil to the conditions of the experiment by USLE and RUSLE model. The treatments with two replications, were constituted in slope length of 11 m, 22 m, 33 m and 44 m, at an average gradient of 8%, in soil cultivated with corn prior to the survey. At the end of the evaluation period, the shoot residue was removed from the surface, leaving the crop roots in bare soil and discovered. We evaluated the erosion between 04/07/2014 and 06/18/2015 in individual events of 41 erosive rainfall. The PS were adjusted to the slope of 0.09 m m-1 (standard for the Universal Soil Loss Equation - USLE), through the factor S. Erosive rainfall totaled 1,349 mm, with Ei30 of 6,066 MJ mm ha-1-h-1. Soil losses increased with increasing slope length and were greater in the summer and spring than in autumn and winter; water losses showed the same trend, with lower among slope lengths and these seasons. Soil and water losses by erosion related to linear and positively with the erosivity and the rain height, respectively. Soil losses were satisfactorily estimated by USLE and RUSLE, with lower than those observed in the field values, keeping a linear and positive relationship between the variables. The RUSLE estimated soil losses better than the USLE, compared to those observed in the field, especially in longer lengths slopes. Soil losses estimated by RUSLE related to linear and positively with these estimated losses USLEA erosão hídrica degrada o solo e contamina o ambiente, influenciada, dentre outros fatores, pelo comprimento de declive. Com este trabalho objetivou-se quantificar as perdas de solo (PS) e de água (PA) em diferentes comprimentos de declive num CAMBISSOLO HÚMICO ALUMÍNICO léptico, em experimento de campo, em condição de chuva natural, em Lages, SC e estimar as perdas de solo para as condições do experimento pelo modelo USLE e RUSLE. Os tratamentos, com duas repetições, constituíram-se nos comprimentos de declive de 11 m, 22 m, 33 m e 44 m, em uma declividade média de 8%, em solo cultivado com milho anteriormente à pesquisa. Ao final do ciclo do milho, o resíduo da parte aérea foi removido da superfície, permanecendo as raízes da cultura em solo sem cultivo e descoberto. Avaliou-se a erosão entre 04/07/2014 e 18/06/2015, em eventos individuais de 41 chuvas erosivas. As PS foram ajustadas para a declividade de 0,09 m m-1 (padrão para a Equação Universal de Perda de Solo - USLE), por meio do fator S. As chuvas erosivas totalizaram 1.349 mm, com EI30 de 6.066 MJ mm ha-1 h-1. As perdas de solo aumentaram com o aumento do comprimento de declive e foram maiores no verão e na primavera do que o no outono e inverno; as perdas de água apresentaram a mesma tendência, com menores variações entre os comprimentos de declive e as referidas estações do ano. As perdas de solo e água por erosão hídrica relacionaram-se linear e positivamente com a erosividade e com a altura de chuva, respectivamente. As perdas de solo foram satisfatoriamente estimadas pela USLE e RUSLE, com valores menores do que os observados em campo, mantendo uma linear e positiva relação entre as variáveis. A RUSLE estimou melhor as perdas de solo do que a USLE, em comparação aos valores observados em campo, especialmente em comprimentos de declives mais longos. As perdas de solo estimadas pela RUSLE relacionaram-se linear e positivamente com as referidas perdas estimadas pela USLECoordenação de Aperfeiçoamento de Pessoal de Nível Superio

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

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 in soil runoff, and to calculate the enrichment rates and the cost of these losses. The treatments evaluated were: a) soil with a crop, consisting of conventional tillage with one plowing + two harrowings (CT), minimum tillage with one chisel plowing + one harrowing (MT), and no tillage (NT); and b) bare soil: one plowing + two harrowings (BS). In CT, MT, and NT, black oat, soybean, vetch, corn, turnip, and black beans were cultivated. Over the 15 years, 15.5 Mg ha-1 of limestone, 525 kg ha-1 of N (urea), 1,302 kg ha-1 of P2O5 (triple superphosphate), and 1,075 kg ha-1 of K2O (potassium chloride) were used in the soil. The P, K, Ca, Mg, and organic C contents in the soil were determined and also the P, K, Ca, and Mg sediments in the runoff water. From these contents, the total losses, the enrichment rates (ER), and financial losses were calculated. The NT increased the P, K, and organic C contents in the topsoil. The nutrients and organic C content in the runoff from NT was greater than from CT, showing that NT was not a fully conservationist practice for soil. The linear model y = a + bx fit the data within the level of significance (p≤0.01) when the values of P, K, and organic C in the sediments from erosion were related to those values in the soil surface layer. The nutrient and organic C contents were higher in the sediments from erosion than in the soil where the erosion originated, generating values of ER>1 for P, K, and organic C. The value of the total losses of nutrients in the form of triple superphosphate fertilizer, potassium chloride, and urea and limestone by water erosion was higher in CT than in NT. For triple superphosphate, the cost of erosion losses was 29 % higher in NT than in CT, while in urea and limestone, the effectiveness of NT in reducing costs was 65 and 50 %, respectively

WATER EROSION UNDER THREE TILLAGE METHODS IN A CULTIVATION OF Eucalyptus benthamii

ABSTRACT Soil tillage influences the development of forests planted in the initial phase, which affects some hydrological processes and water erosion. The objective of this study was to quantify the water losses (WL) and soil losses (SL) by water erosion, between the second and third years of eucalyptus (Eucalyptus benthamii) crop, in an experiment located in southern Brazil, on a Humic Dystrudept. Was study three soil tillage treatments: i) subsoiling in downslope direction (SD); ii) subsoiling in contour on the slope (SC); iii) manual holes (MH). The plots had a dimension of 12 x 24 m, being the slope-wise length the greatest, monitored by tanks placed at the lower end for runoff collection. Runoff volume measurement and sampling for subsequent calculation of WL and SL was carried out weekly, corresponding to the rains accumulated during the week. The crop of eucalyptus in SD treatment, weakened the soil as to the water erosion in relation to the crop made in SC and in MH; the difference was 25% for the WL and 53% for the SL. Eucalyptus reforestation played an important role in the control of water erosion, regardless of the type of soil tillage. The SL due to water erosion were more influenced than the WL, regardless of the type of soil crop used. WL and SL are related to each other and to rainfall height in positive linear relationship, regardless of the type of soil preparation used for eucalyptus planting