relatório final

A educação pré-escolar é a primeira etapa da educação básica no processo de formação ao longo da vida, prolongando-se com carácter obrigatório no 1.º ciclo do ensino básico. Estas etapas assumem grande importância para o sucesso educativo da criança e para o seu projeto de vida futuro. Cabe aos profissionais da educação, o desafio de implementar dinâmicas pedagógicas que permitam a aquisição de competências e a formação do indivíduo enquanto cidadão. O propósito deste trabalho é apresentar o percurso das aprendizagens realizadas no âmbito destas realidades, pelo que se tentou compreender a perspetiva das crianças, assim como as especificidades inerentes à profissão. O presente relatório é constituído por duas partes, sendo que a primeira diz respeito à contextualização do itinerário formativo nos dois contextos e a segunda, relativa às experiências-chave que resultaram das vivências dos estágios. Como reflexão deste percurso de aprendizagem verifica-se a importância do estágio para o trabalho profissional futuro, o qual deve ser norteado pelos interesses e dificuldades das crianças, promovendo a sua autonomia e gosto pela aprendizagem

Efeitos da salinidade e fertilização azotada nos parâmetros hídricos e fotossintéticos na fase inicial de desenvolvimento de Sorgo sacarino (Sorghum bicolor L. Moench)

Utilizando plantas de Sorgo Sacarino, investigou-se a possibilidade de atenuação do efeito inibitório da salinidade pela aplicação de fertilização azotada. As plantas foram crescidas em solo, numa estufa, e regadas com três níveis de solução de cloreto de sódio (0, 5 e 15 g L-1 NaCl) e três níveis de solução de nitrato de amónio (0, 0,4 e 0,6 g L-1 NH4NO3), num desenho experimental 3 × 3, com 4 repetições, num total de 36 vasos. De um modo geral, as plantas toleraram bem a irrigação com 5 g L-1 de NaCl mas mostraram sintomas severos com a irrigação de 15 g L-1. Assim, no final do ensaio, enquanto a biomassa seca das plantas irrigadas com 5 g L-1 era apenas ligeiramente inferior às regadas com água corrente, as plantas regadas com 15 g L-1 tinham menos 80% de peso seco. Os parâmetros fisiológicos medidos mostraram um padrão semelhante ao da biomassa, ou seja, pouco afectados pela menor salinidade mas muito inibidos pela maior (15 g L-1). A fertilização com azoto melhorou o crescimento das plantas e alguns outros parâmetros. Conclui-se assim que, na fase inicial de desenvolvimento das plantas de sorgo (25 dias), objecto deste ensaio, o azoto beneficia o crescimento das plantas expostas ao sal, embora, com base nos valores de fotossíntese, a concentração de 0,4 g L-1 seja mais benéfica que a de 0,6 g L-1

Previsão da salinização e sodicização em solos regados com águas salinas com uso de indicadores de qualidade do solo

Mestrado em Gestão e Conservação de Recursos Naturais - Instituto Superior de Agronomia / Universidade de ÉvoraThis work aims to predict the salinization and sodification in two soils when irrigated with saline waters combined with different fertigation levels. In a three years period, two experimental fields were set up with maize irrigated with a Triple emitter source (TES) irrigation system. The impact in the two soils (Hortic Antrosol and Eutric Fluvisol) was assessed through soil solution and soil samples collected at the end of each irrigation cycle and after the fall/winter rainfall washout of the soil. Electrical conductivity (EC) was used as a salinity indicator, and the exchangeable sodium percentage (ESP) and sodium adsorption ratio (SAR) were used to characterize soil sodicity. In order to predict soil quality, the relationship between such indicators were studied with a stepwise multiple regression analysis scheme in a total of 1500 observations. An exchangeable Na+ mass balance was established for each treatment to 60 cm depth, as the difference between the final and initial total masses. The results confirm that t the Fluvisol shows a tendency towards salinization, since insufficient Na+ lixiviation occurred throughout the soil profile even after the fall/winter rainy season. The Antrosol however showed favourable to salts lixiviation after the irrigation cycles and more so after the rainfall season

Comparative assessment of infiltration, runoff and erosion sprinkler irrigated soils

Abstract The impacts of sprinkler irrigation on infiltration, runoff and sediment loss of ten representative soils of Southern Portugal were assessed by laboratory sprinkler irrigation simulation tests. All soils showed very low permeability to applied water. The mechanical impact of water droplets enhanced soil dispersion and further lowered their infiltration capacity, particularly for high clay plus silt content soils that showed the poorest results. As a consequence, high runoff and sediment losses were also measured, primarily with the first irrigation. More moderate losses were observed thereafter. Soils with higher sand particle size fractions better absorbed the energy impact of droplets and showed higher infiltration rates and lower runoff and sediment losses. Polyacrylamide (PAM) applied to the soils through the irrigation water acted as a binding and settling agent to increase soils aggregate stability and infiltration and reduce runoff and sediment losses. Slope increase, from 2·5 to 5%, decreased overall soils infiltration by 7% and increased runoff and sediment losses by 10 and 27%, respectively. Exposed to the same change in slope, PAM application boosted overall infiltration of treated soils to a 24% difference and increased runoff by only 10%. It had a less positive effect on sediment loss, the 5% slope being responsible for a 52% increase. In agreement with this the tests showed that, compared to the control, exposure of PAM-treated soil on 2·5 and 5% slopes enhanced overall infiltration to 457 and 642% respectively, reduced runoff by 25% on both cases and lessened sediment loss by 39 and 27%. The demonstrated ability of PAM to influence surface soil conditions of specific soils can be used to reduce the environmental risks associated with the intensive use of sprinkler irrigation in Southern Portugal. It offers a safe, practical and non-intrusive management alternative to current costly, labour- and energy-intensive practices of increasing the number of machine turns and building storage basins to control runoff and soil erosion

Sap flow scaling and crop coefficient of dry-farmed olive orchards converted to irrigation

Tree water uptake is often estimated based in a crop coefficient kc, a ratio of the tree water uptake and a reference evapotranspiration, ET0. The concept behind estimating tree crop coefficient implies that data should be representative of the population of trees analyzed. Ideally it would require the monitoring of a large number of trees in each treatment population. This paper reports on a scaling method to establish stand-level transpiration estimates and crop coefficients from individual sampled tree sap flow measurements. The scaling technique was implemented for individual tree sap flow measurements on the following irrigation treatments: A, fully-irrigated; B, irrigated to provide for approximately 60% of crop evapotranspiration; C, irrigated to provide for 100% of crop evapotranspiration during three critical phase periods: before-flowering, at beginning of pit-hardening and before crop-harvesting, and dry-farming treatment D. Results show that stand transpiration T depart from individual tree transpiration values. They consequently were used to establish crop, kc and water stress, ks coefficients to account for the cluster’s characteristics and degree of tree’s water uptake. Using the individual tree transpiration rates would be less appropriate

Water use and response of a dry-farmed olive orchard recently converted to irrigation

Experimental results obtained in Southern Portugal from a dry-farmed mature olive tree orchard recently converted to drip irrigation are described. Water use and response to two irrigation management practices by olive trees was monitored with sap flow compensation heat pulse sensors, ‘Watermark’ granular matrix block sensors and a capacitance probe. The 80-plus-year-old mature olive tree orchard planted on a 12 m by 12 m spacing layout was converted in 2005 from dry-farming to drip irrigation and subjected to two water treatments: trees irrigated daily to supply for crop water demand and trees irrigated before-flowering, during pit-hardening and before crop-harvesting. Sap flow sensors were implanted in sample trees at three different positions around the trunk and measurements were taken at 30 min intervals during 4 months, from April to mid-August of 2005. Tree transpiration rates were estimated as average of sap flow rates. When trees were fully irrigated, the observed differences in daily sap flow rate amplitude were explained by the natural trees difference in canopy cover, plant height and conductance of water vapour sites. However, when deficit irrigation was prescribed and, when the trees stopped being irrigated, they gradually lost their ability to adequately respond to the evaporative demands of the day, showing smaller variations in amplitudes sap flow. After irrigation ceased in May 15, transpiration rate gradually decreased from its maximum of 7 l h−1, when trees were fully irrigated and soil water content was near to field capacity, to values of less than 3 l h−1 by July 3 as the soil water content gradually acted as the transpiration limiting factor. Transpiration rates recovered after irrigation was re-introduced on July 4. Although low in the non-irrigation period, transpiration rates never dropped to zero and stayed between 37 and 50 l d−1 from May 27 to June 9, as trees were able to extract soil water in the absence of irrigation. Olive trees maintained transpiration to levels as high as 50 l d−1 suggesting that long after irrigation is suppressed, a considerable amount of water held in the soil is made available to the trees. Differences in evapotranspiration and transpiration rates during the same period also indicated that olive trees, making use of the extensive root system developed in the 12 m by 12 m tree spacing, were able to extract soil water and maintain transpiration levels as high as 50 l d−1, while soil water balance indicated tree evapotranspiration rates close to zero. This particular ability of dry-farmed olive trees to remove water held in the soil under adverse conditions of very low soil moisture and uncertainties associated with the real volume of soil effectively explored by the root system, make profile probe sensors, regardless of their accuracy, unsuitable for control of water uptake and management of dry-farmed olive orchards recently converted to irrigation. Likewise, watermark sensors, able to capture the variations of high soil water, failed to provide meaningfully values below 0.28 cm3 cm−1. Both sensors should be used with care in managing irrigation of olive tree orchards and, rather than relying on soil moisture status, monitoring tree water-use and response with the compensation heat-pulse method seems a more appropriate approac

Using polyacrilamide with sprinkler irrigation to improve infiltration

ABSTRACT: Center-pivot irrigation systems often apply water at rates greater than the soil infiltration rate. Applying high molecular weight, water-soluble, anionic polyacrylamide (PAM) to the soil can improve infiltration and reduce soil erosion The objective of this study was to determine whether single and multiple PAM applications with sprinkler irrigation improved infiltration under field conditions. A two-year study conducted near Kimberly, Idaho, used a solid-set sprinkler system, and a one-year study conducted in Monte dos Alhos near Alvalade do Sado, Portugal, used a center pivot. At Kimberly, applying PAM with four irrigations (total applied PAM was 2.1 kg ha−1 in 2000 and 3.0 kg ha−1 in 2001) significantly reduced total measured runoff, from 5.9 mm (2000) and 9.2 mm (2001) for the control to 2.0 and 2.1 mm. Total measured soil erosion was also reduced from 52 and 34 kg ha−1 for the control to 21 and 5 kg ha−1 for the multiple PAM treatment. Applying similar or greater amounts of PAM with a single irrigation reduced erosion, but not runoff, compared with the control. In the Monte dos Alhos study, runoff was reduced by applying a total of 0.3 kg PAM ha−1 with a single irrigation (43 mm runoff) or three irrigations (65 mm runoff) compared with the control (111 mm runoff). Measured soil erosion was not significantly different among treatments. Applying PAM with multiple irrigations extended its effectiveness as long as the application rate was great enough to adequately stabilize the soil surface during the first irrigation

Association between serum levels of C-reactive protein and lipid profile

info:eu-repo/semantics/publishedVersio

Assessing soil salinity dynamics using time-lapse electromagnetic conductivity imaging

LezíriaGrandedeVilaFrancadeXira,locatedinPortugal,isanimportantagriculturalsystemwhere soil faces the risk of salinization due to climate change, as the level and salinity of groundwater are likely to increase as a result of the rise of the sea water level and consequently of the estuary. These changes can also affect the salinity of the irrigation water which is collected upstream of the estuary. Soil salinity can be assessed over large areas by the following rationale: (1) use of electromagnetic induction (EMI) to measure the soil appar- ent electrical conductivity (ECa, mS m−1); (2) inversion of ECa to obtain electromagnetic conductivity imaging (EMCI) which provides the spatial distribution of the soil electrical conductivity (σ,mSm−1); (3) calibration process consisting of a regression between σ and the electrical conductivity of the saturated soil paste extract (ECe, dS m−1), used as a proxy for soil salinity; and (4) conversion of EMCI into salinity cross sections using the obtained calibration equation. In this study, EMI surveys and soil sampling were carried out between May 2017 and October 2018 at four locations with different salinity levels across the study area of Lezíria de Vila Franca. A previously developed regional calibration was used for predicting ECe from EMCI. Using time-lapse EMCI data, this study aims (1) to evaluate the ability of the regional calibration to predict soil salinity and (2) to perform a preliminary qualitative analysis of soil salinity dynamics in the study area. The validation analysis showed that ECe was predicted with a root mean square error (RMSE) of 3.14 dS m−1 in a range of 52.35 dS m−1, slightly overesti- mated (−1.23 dS m−1), with a strong Lin’s concordance correlation coefficient (CCC) of 0.94 and high linearity between measured and predicted data (R2 = 0.88). It was also observed that the prediction ability of the regional calibration is more influenced by spatial variability of data than temporal variability of data. Soil salinity cross sections were generated for each date and location of data collection, revealing qualitative salinity fluctuations related to the input of salts and water either through irrigation, precipitation, or level and salinity of groundwater. Time-lapse EMCI is developing into a valid methodology for evaluating the risk of soil salinization, so it can further support the evaluation and adoption of proper agricultural management strategies, especially in irrigated areas, where continuous monitoring of soil salinity dynamics is required.info:eu-repo/semantics/publishedVersio

QUALITY OF BLACK PEPPER PRODUCED IN NORTHEASTERN PARÁ

Black pepper (Piper nigrum L.) is the most widely used spice in the world. This crop has great economic importance in Brazil, especially in the North and Southeast regions. However, the variability in quality between cultivars is high. The objective of this study was to characterize black pepper from northeastern Pará available on the market and obtain an overview of its quality parameters. A total of 23 samples from black pepper cultivars/clones were evaluated for impurities and foreign matter, empty grains, density, moisture and ether extract, as established by Brazilian legislation. Additionally, the contents of total ash, protein, crude fiber and piperine were determined. Among the samples, one was outside the standard for density. The moisture contents were below the maximum limit required by the legislation, demonstrating that the drying and storage of the grains were adequate. Regarding the ether extract, 52% of the samples did not meet the commercialization standards. Concerning piperine, the Equador and Panny clones had levels greater than 5%. It was found that the nutritional composition of black pepper is influenced by the technological level of the production system. In summary, black pepper produced in northeastern Pará has variable quality.A pimenta-do-reino (Piper nigrum L.) é a especiaria mais utilizada no mundo. No Brasil, essa cultura tem grande importância econômica, em especial às regiões Norte e Sudeste. Entretanto, a variabilidade na qualidade entre as cultivares é alta. O objetivo deste trabalho foi caracterizar a pimenta preta do nordeste do Pará disponibilizada no mercado, obtendo-se um panorama quanto aos parâmetros de qualidade. Foram avaliadas 23 amostras de pimenta preta de cultivares/clones quanto às impurezas e matérias estranhas, grãos chochos, densidade, umidade e extrato etéreo, conforme estabelecido pela a legislação nacional. Também, foram determinados os teores de cinzas totais, proteínas, fibra bruta e piperina. Dentre as amostras, uma estava fora do padrão para densidade. Os teores de umidade encontravam-se abaixo do limite máximo exigido pela legislação, demonstrando que a secagem e o armazenamento dos grãos foram adequados. Em relação ao extrato etéreo, 52% das amostras não atenderam aos padrões de comercialização. Quanto à piperina, os clones Equador e Panny destacaram-se com teores superiores a 5%. Verificou-se que a composição nutricional da pimenta preta sofre influência do nível tecnológico do sistema de produção. Portanto, a pimenta preta produzida no nordeste do Pará tem qualidade variável