Navegando por Assunto "Fertilidade do solo"

Agora exibindo 1 - 4 de 4

Acesso aberto (Open Access)
Assinaturas geoquímicas dos perfis de solo do sítio arqueológico do município Bom Jesus do Tocantins – Pará
(Universidade Federal do Pará, 2010-12-07) SILVA, Any Kelly Terra da; KERN, Dirse Clara; http://lattes.cnpq.br/8351785832221386; LEMOS, Vanda Porpino; http://lattes.cnpq.br/1829861620854008
The integration of morphological, mineralogical and chemical data of a soil with Archeological Black Earth (ABE) and surrounding Argissolos allowed to indentify the main process acting on the ABE formation from Bom Jesus do Tocantins, southeast Pará State. The similarity between these data in the subsurface horizon of ABE and surrounding soils indicate that ABE was probably developed from Argissolos with subsequent pedogenetic transformation through the input of organic and inorganic materials (kitchenware, foods and other materials of animal and vegetable origin) by ancient human settlements that promoted the thickness of the surface horizon and higher concentrations of CaO, P2O5, Zn, available P and Zn, and exchangeable Ca and Mg in relation to surrounding Argissolos. Furthermore, this anthropic influence also resulted in changes of subsurface horizon of Argissolos with ABE, such as high concentrations of P2O5 and available P. The Soil Taxonomy and Brazilian System of Soil Classification (BSSC) are suitable to identify ABE, since they prioritize in the soil orders the main pedogenetic process acting on soil formation and development, related to the subsurface horizon, and subsequent pedogenetic transformations in the surface horizon. Moreover, this study propose the addition of diagnostic properties such as ceramic and lithic artifacts, P2O5 and available P and Zn, organic carbon, Ca2++ Mg2+, CEC and base saturation index in the surface horizon of Soil Taxonomy and BSSC to group and differentiate several types of anthropic soils of Amazon region.
Acesso aberto (Open Access)
Fertilidade e fauna edáfica em solo sob reflorestamento com paricá (Schizolobium amazonicum Huber ex Ducke) no município de Aurora do Pará
(Universidade Federal do Pará, 2011-02-28) PEREIRA JÚNIOR, Antônio; ROCHA, Edson José Paulino da; http://lattes.cnpq.br/2313369423727020; RUIVO, Maria de Lourdes Pinheiro; http://lattes.cnpq.br/9419564604488031
This study aimed to evaluate the variation in soil fertility and soil fauna under reforestation paricá (Schizolobium amazonicum Heber ex. Ducke) in monoculture or agroforestry system compared with secondary forest in the experimental area considering the seasonality of precipitation in the period 2009 and 2010. The experimental farm owned by Tramontina Belem S / A, located in northeastern Pará, in the city of Aurora do Pará Four treatments were analyzed undergoing reforestation: Curaua (Ananas comosus var. Erectifolius L.B.Smith) Parica (Shizolobium var. Amazonicum Huber ex Ducke) in the form of monoculture, Parica + curauá (Ananas comosus var. erectifolius L.B.Smith; Shizolobium var. amazonicum Huber ex Ducke); Parica Mahogany + Freijó Curaua (Shizolobium var. amazonicum Huber ex Ducke, Swietenia macrophylla, King, Cordia goeldiana Huber, Ananas comosus var. erectifolius LB.Smith). Samples were taken in December 2009, April and July 2010, which marked the seasonal transition period (dry to heavy rain), heavy rain and dry seasons respectively, to evaluate the particle size, bulk density, particle density, porosity and moisture content, exchangeable bases, total bases, CEC, acidity, phosphorus, organic carbon, pH, at three different depths (0 - 10 cm. 10 to 20 cm, 20-40 cm) and the occurrence of macrofauna. The results showed the action of the seasons on the bulk density, particle density, total soil porosity. Chemical factors, eg, organic carbon, whose contents varied between 5.85 g / kg and 13.00 g / kg, at high levels in the culture system S2, changed during intense rainfall seasons and drought. As for soil fauna, 9964 invertebrates were captured belonging to 26 different taxa. The most abundant were Hymenoptera – Formicidae (5.805), Coleoptera (1.454), Acari (862) Collembola (649), Diplopoda (307) and Isopoda (110). Of the 26 taxa identified, approximately 40% of them showed only a representative sampling carried out in three or just one. The highest values for relative frequency occurred in the cropping system S2, S3 and S4, respectively. The highest value of absolute frequency occurred during seasonal rainstorms in S1. Areas under reforestation and agroforestry monoculture Parica + curauá showed better performance in the recovery of soil fertility and soil fauna proving the efficacy of paricá in monoculture or agroforestry system in the recovery of soil fertility and soil fauna.
Acesso aberto (Open Access)
Influência da variação sazonal de atributos de fertilidade do solo sobre a biomassa microbiana em uma cronosseqüencia de plantio de palma de óleo (Elaeis oleifera (Kunth) Cortés) no Nordeste Paraense
(Universidade Federal do Pará, 2013-02-19) SILVA JUNIOR, Alberto Cruz da; RUIVO, Maria de Lourdes Pinheiro; http://lattes.cnpq.br/9419564604488031
Brazil has about 32 million hectares of areas with capability to oil palm’s expansion and more than 90% of these are in the Amazon. There is need to understand the interaction of new plantations and its development with the environment. This study was conducted in Dende do Pará SA (DENPASA), commercial plantations company, and aimed to evaluate precipitation’s seasonal variation on the soil fertility and thus on soil biomass in a chronosequence of oil palm plantations with 5, 8 and 12 years and secondary forestry. We measured / estimated and correlated the attributes carbon microbial biomass (CSMB), total carbon (CTOTAL), total nitrogen (NTOTAL), soil basal respiration (SBR), metabolic quotient (qCO2), carbon microbial biomass / total carbon ratio (CBMS: CTOTAL), carbon / nitrogen ratio (C / N), gravimetric moisture (Ug), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum (Al), effective exchange capacity of cations (CTC) and aluminum saturation (m). The CBMS was the attribute most sensitive to differentiate areas of study and dry and rainy seasons. Chemical characteristics of soil fertility and soil microbial biomass were correlated stronger and in greater numbers during the rainy season. Chemical attributes of soil fertility and soil microbial biomass presented correlation more strong and in greater numbers during the rainy season. The microbial indices qCO2 and CBMS:CTOTAL proved that conventional planting areas can be relatively efficient in relation to C dynamics compared to secondary forest area.
Acesso aberto (Open Access)
Passivo ambiental de nutrientes e matéria orgânica na agricultura empresarial de Mato Grosso
(Universidade Federal do Pará, 2017-04-24) GOMES, Vallência Maíra; CAMPOS, Índio; http://lattes.cnpq.br/9134366210754829
The intensive exploitation of soils of Mato Grosso-Brazil savanna, associated with inadequate farming techniques has taken to an increasing and noticeable soil degradation. As a result, grows among the large farmers of Mato Grosso the adoption of the no-tillage system. The environmental chemistry and agronomy allied to ecological economics and environmental management provide the interdisciplinary basis of this study, which aims to estimate the environmental liability of nutrients and organic matter of the soil in the mato-grossense savanna from the perspective of the economic viability of different soil management systems. After the identification of areas in which the environmental costs were or were not incorporated, was made the economic-financial feasibility analysis, considering the different types of management. The results point to a segmented reduction of environmental liabilities in areas where no-till farm system is adopted. However, in the short term, higher profitabilities is still combined with less sustainable traditional management techniques. However, other externalities are still associated of the no-tillage not addressed in this study, such as more intensive use of herbicides and insecticides, which may compromise its environmental results.