MANEJO DA AVEIA PRETA NA DECOMPOSIÇÃO DA BIOMASSA E NA COBERTURA DO SOLO EM SEMEADURA DIRETA DE MILHO

Com o objetivo de avaliar a decomposição e o índice de cobertura de aveia preta (Avena strigosa Schreb) em sucessão com milho (Zea mays L.) em semeadura direta, foi conduzido um experimento no período de julho de 2006 a abril de 2007, no município de Ponta Grossa, PR. O delineamento experimental utilizado foi de blocos ao acaso com parcelas subdivididas e quatro repetições. Os tratamentos principais foram os métodos mecânicos de manejo: rolo-faca antes do plantio, rolo-faca pós-plantio, roçadora e triturador, enquanto que os tratamentos secundários foram com e sem dessecação. Avaliou-se o índice de cobertura da aveia e a produção de biomassa seca ao longo do ciclo da cultura do milho. As taxas de decomposição da aveia preta e índices de cobertura diferiram estatisticamente apenas na segunda avaliação (22 dias após semeadura do milho). O rendimento de grãos de milho não apresentou diferenças estatísticas para os métodos testados

Characterization of Highly Weathered Soils

Os solos brasileiros são classificados em 13 ordens, com base em suas características definidoras. Os latissolos e os ultissolos predominam, compreendendo mais de 50% de todo o território. Portanto, o objetivo deste trabalho foi estudar os principais atributos físicos do solo e o conteúdo de matéria orgânica para avaliar as atribuições e limitações de dois tipos de solos altamente intemperizados no extremo oeste de São Paulo. O delineamento experimental foi inteiramente casualizado, composto por dois tratamentos diferentes: Latossolo e Ultisol em três faixas de profundidade: 0,00-0,10, 0,10-0,20, 0,20-0,40 m, com 10 repetições. As análises foram realizadas em triplicado. Os seguintes atributos do solo foram avaliados: textura do solo, conteúdo de matéria orgânica, umidade volumétrica e gravimétrica, infiltração de água no solo, densidade do solo, porosidade do solo, distribuição e estabilidade dos agregados, resistência à penetração e umidade do solo. Os dados foram analisados ​​quanto à variância com o teste F, a p ≤ 0,05. Quando significativos, os parâmetros foram submetidos ao teste de Tukey (p <0,05). As propriedades físicas do solo mostram que os solos estudados estão em boas condições e dentro dos limites médios recomendados pela literatura estabelecida. Todos os atributos estudados estão relacionados à granulometria do solo e sua distribuição no perfil do solo

Manejo da aveia preta na decomposição da biomassa e na cobertura do solo em semeadura direta de milho

With the objective of evaluating the decomposition and soil cover of black oat (Avena strigosa Schreb) in succession with maize (Zea mays L.) in no-tillage system, it was installed an experiment in Ponta Grossa - PR, Brazil. The experiment was laid out as random block design with split-plot and four replications. The main treatments were composed by four mechanical management systems of oat ( knife-rolled before and after seeding of maize, shredder and chopper) set up in 14.4 x 6 m plots. The split-plot (7.2 x 6m) treatments were with and without chemical desiccation with glyphosate. It was evaluated the index of cover of the oat and the output of dry biomass throughout the cycle of the culture of the maize. The rates of decomposition of the black oat and index of soil cover had differed statistically only in the second evaluation (22 days after seeding of the maize). Maize grain yield in succession to oat was not influenced by management systems of oat strawCom o objetivo de avaliar a decomposição e o índice de cobertura de aveia preta (Avena strigosa Schreb) em sucessão com milho (Zea mays L.) em semeadura direta, foi conduzido um experimento no período de julho de 2006 a abril de 2007, no município de Ponta Grossa, PR. O delineamento experimental utilizado foi de blocos ao acaso com parcelas subdivididas e quatro repetições. Os tratamentos principais foram os métodos mecânicos de manejo: rolo-faca antes do plantio, rolo-faca pós-plantio, roçadora e triturador, enquanto que os tratamentos secundários foram com e sem dessecação. Avaliou-se o índice de cobertura da aveia e a produção de biomassa seca ao longo do ciclo da cultura do milho. As taxas de decomposição da aveia preta e índices de cobertura diferiram estatisticamente apenas na segunda avaliação (22 dias após semeadura do milho). O rendimento de grãos de milho não apresentou diferenças estatísticas para os métodos testado

Long-Term Integrated Crop–Livestock–Forestry Systems Recover the Structural Quality of Ultisol Soil

Integrated Crop–Livestock–Forestry Systems (ICLFS) offer stakeholders sustainable options to produce goods and services. Those additionally manifest as enablers of environmental conservation of soil functioning. We, therefore, analyzed the quality of Ultisol for physical and chemical properties under restorative or regenerative models of long-term (nine years) ICLFS. The arrangements comprised integrated Crop–Livestock; integrated Crop-Livestock-Forestry, integrated Crop–Livestock–Forestry with a single or triplicate rows of Eucalyptus; and Eucalyptus plantation, natural vegetation, and bare soil with resurgence of grasses (reference). We collected samples of soil at 0.05, 0.05–0.1, and 0.1–0.2 m depths throughout the areas to quantify standard properties, including water infiltration, hydraulic conductivity, degree of flocculation, mechanical resistance to penetration, stability of aggregates, physical fractioning of organic matter, and fertility. We applied principal component analysis to analytical data to calculate accurate discriminant variables to distinguish systems by structural quality. We obtained evidence for the crop–livestock framework improving physical and chemical properties; hence, this intervention outperformed others in developing environmental restoration. Additionally, as the reference consisted of comparable properties to those in integrative systems and native vegetation, it supported the ability of the soil to gradually recover itself over time. Therefore, our study provides knowledge to advance the field’s prominence in implementing ICLFS for the environmental reclamation of the condition or process degrading the soil and its functions for sustainable agricultural production

The relationship between the level of vitamin D and ruptured intracranial aneurysms among patients with high sun exposure

Abstract Non-traumatic subarachnoid hemorrhage (SAH) accounts for 3–5% of acute strokes. Intracranial aneurysm is the most common cause of non-traumatic SAH. Vitamin D influences the cardiovascular system, including the formation and rupture of cerebral aneurysms. To evaluate the serum vitamin D level in patients living in the tropical zone who suffered aneurysmal subarachnoid hemorrhage and its correlation with demographic and neurological characteristics. This is an analytical cross-sectional study to assess the serum level of vitamin D in a study population of 99 patients treated and diagnosed with aSAH in a public hospital in Recife-PE over a period of 12 months. In the study sample, composed of individuals with high sun exposure due to the lifestyle they lead in a tropical region, we observed hypovitaminosis D (85.9%), with a median of 19.9 ng/ml, although the majority of individuals are skin with high concentration of melanin (Fitzpatrick skin type IV and V). In addition, rates of sun exposure are high to all patients (Solar Index 9.03 P50). Most individuals were female (79.8%); there was no statistical difference in solar exposure/solar index between genders. As for the neurological repercussions, there was no statistical relevance in the clinical prognostic scales evaluated. As the sample was composed mainly of individuals whose economic activity is agriculture, the values of solar index found are vastly higher than those of other studies conducted in high latitude regions. In line with the literature review, some aspects were raised with the objective of justifying such findings that go from the base of the poor diet of these individuals, the increase of melanin in the skin and genetic alterations that directs us to possible mechanisms of natural photoprotection to high sun exposure. Thus, we had a vast majority (85%) of hypovitaminosis D, which in fact makes us wonder if there is any influence of calcitriol on vitamin D receptors in vascular walls and in the cardiovascular system as a whole, which influence bleeding events of this nature. As for the neurological repercussions, measured using assessment scales (Glasgow coma scale, WFNS scale, Hunt–Hess and Fisher's tomographic scale) there was no significant difference in the results. As it is only a descriptive study, the causal relationship of the facts cannot be established. However, in a population exposed to high sun exposure and affected by aneurysmal SAH, there is a significant rate of hypovitaminosis D, which supports the hypothesis that vitamin D plays a role in vascular pathologies, such as cerebral aneurysms and SAH