Diego Bortolini

Altura de manejo de papuã e propriedades de solo em sistema de integração lavoura-pecuária

No sul do Brasil, ha ocorrencia espontânea de papua (Urochloa plantaginea (Link) R.D. Webster), nas lavouras, no periodo de verao, sendo que essa planta possui grande potencial forrageiro. Neste trabalho, objetivou-se avaliar as alteracoes ocorridas nas caracteristicas fisicas e na materia orgânica do solo, em pasto de papua, com diferentes alturas de manejo, na presenca e na ausencia de pisoteio animal. O trabalho foi realizado na Estacao Experimental do IAPAR, no municipio de Pato Branco, Parana. O delineamento experimental utilizado foi o de blocos casualizados com tres repeticoes. Os tratamentos foram arranjados em esquema bifatorial, com parcelas subdivididas, durante o periodo de pastejo. As parcelas receberam os niveis do fator altura de manejo de pasto de papua (0,1; 0,2; 0,3 e 0,4 m), enquanto as subparcelas foram constituidas de areas com (pastejadas por cabras) e sem pisoteio animal (corte manual). Foram avaliados, apos o periodo de pastejo, os teores de materia orgânica, a densidade, a porosidade total, a macro e a microporosidades do solo. De maneira geral, a altura de manejo do papua, na presenca, ou nao, de pisoteio animal, nao alterou significativamente as caracteristicas fisicas e a materia orgânica do solo, avaliadas apos o primeiro ciclo de aplicacao dos tratamentos. O pisoteio animal nao causou compactacao adicional e, mesmo com pastejo animal, os teores de materia orgânica no solo mantiveram-se altos.

Semeadura direta com diferentes mecanismos sulcadores: alterações em propriedades de um Latossolo Bruno e produtividade das culturas

The mechanisms of seeding machines to cut the mulch, mobilize the topsoil and deposit the seeds in the furrows modify soil properties and interfere in crop growth. This study sought to evaluate the effects of furrow openers and scarification on the attributes of a South Brazilian latosol (Bruno – oxisol) and crop yields. The treatments were: double disc furrow opener (DD); shovel type furrow opener (S); shoe type furrow opener (SH); and scarification followed by double disc furrow opener (SC+DD). Samples were collected at 0-10, 10-20 and 20-40 cm and evaluated for soil physical (bulk density, total porosity, macro and microporosity), chemical (pH, Ca, Mg, K and P) and organic carbon content. The normality of data was tested, and the analysis of the variance was performed (F test, p<0.05), and the means was compared by Tukey’s test (p=0.05). Soil attributes were analyzed for each layer separately. After four years it was observed that the bulk density is still affected by scarification, which reduces it. The successive use of DD in the winter for the implantation of the crops caused the homogenization of the soil, although with no differences on the other physical and chemical properties. In general, grain yield and dry mass were higher in the treatment that used scarification and the double disc during the summer, and the shoe type when compared to shovel type.

Propriedades físicas do solo em sistema de integração lavoura-pecuária em Cambissolo Húmico

In integrated crop-livestock systems under a no-tillage system, the action of animal trampling can influence the physical properties of the soil, depending on the intensity of grazing and stocking rate. This study aimed to evaluate the physical properties of a Humic Cambisol, under an integrated crop-livestock system submitted to different grazing intensities of lactating cows in the city of Lages, SC. The treatments constituted three forage masses of winter pasture (low, medium and high), and a control area, with no grazing (no grazing), oat and ryegrass consortium was used, then the density, hydraulic properties of the soil, organic matter content, aggregation and soil penetration resistance were evaluated. Generally the animal trampling had no significant influence on physical properties, the dynamics of water and the contents of soil organic matter. The macroporosity conditions, as well as high resistance to penetration, principally in conditions of low moisture, prove that the Humic Cambisol of the franc silty clay texture provides a constraint physical problem.