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Sirvi Autor "Pedro, N." järgi

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  • Pisipilt
    Kirje
    Analysis of the relationship between the weather index of fire danger and occurrences of rural fires. Case study: centro region of Portugal
    (Estonian University of Life Sciences, 2024) Fernandez, P.; Bugalho, L.; Pedro, N.
    The aim of this study was to design an approach for establishing a plausible relationship between FWI and the monthly average burned area (ABA) and the average number of ignitions (ANI) supported by geographic information systems (GIS). The application of these results will allow the projection of burned areas in forest fires in the future, making mitigation actions possible. This approach was applied to the region of Central Portugal, and to achieve the aims of the study, the following steps were completed: (1) geoprocessing the spatial data of the daily FWI indices, burned area and number of fire ignitions and (2) developing statistical regression models capable of reproducing the variability in burned area and ignition occurrence series from FWI data during the 2001–2017 period. The predicted equations for the burned area as a function of the FWI presented high coefficients of determination for most of the considered periods, thus allowing the projection, with a high degree of confidence, of the monthly burned area values according to the various future climate scenarios. The prediction of the average number of ignitions from the FWI values class proved to be effective for establishing highly adjusted forecast models for July and August. In the spatial analysis at the district level, the ABA and ANI estimation equations were obtained from the FWI values with determination coefficients above 0.90 for most of the districts. Significant differences were observed between the districts in the number of ignitions analysed.
  • Pisipilt
    Kirje
    GIS-based analytic hierarchy process model for a forest residuals biorefinery site selection
    (Estonian University of Life Sciences, 2024) Pedro, N.; Quinta-Nova, L.
    In general terms, renewable energy sources are characterized by their decentralized availability, ability to quickly self-regenerate, and the reduced environmental impacts resulting from their use. The conversion of forest biomass into energy will make it possible to transform waste into raw material for the energy industry while promoting forest management. Reducing the forest's fuel load will be responsible for reducing the intensity of forest fires. In this context, biorefineries significantly prevent rural fire risks by addressing two important aspects: fuel management and renewable energy generation. based on these premises, this study aims to assess the potential for implementing a biorefinery in the Centro Interior region. The amounts of available residual biomass were calculated based on data from the national forest inventory, carried out in 2015.For the municipalities with higher residual biomass production, a decision support system based on GIS and Multicriteria Decision-making was used to select sites suitable for locating a forest biorefinery and provides a valuable reference for decision-makers. The combination of MCDM and GIS methods can, therefore, be seen as a powerful tool for solving power planning problems. The most relevant areas, in terms of land occupation of the three forest species considered, are mainly found in the south of the region under study. The area under study has the potential to generate an annual flow of residual biomass of 269,024 tons per year, with maritime pine harvesting accounting for 80% of this flow. However, around 88,193 tons of the annual flow of residual biomass (33%) are found in regions that are difficult to access, and the costs may make exploration unviable in economic terms. According to the study carried out, we consider that the implementation of the biorefinery will be located in the industrial area of the municipality of Oleiros.
  • Pisipilt
    Kirje
    Production of simple sugars from olive grove pruning using acid pretreatment and enzymatic hydrolysis
    (Estonian University of Life Sciences, 2024) Pedro, N.; Bezerra, R.; Fraga, I.; Duarte, A.P.
    The purpose of this paper was to optimize the production of simple sugars from olive grove pruning (OGP) using acid pretreatment and enzymatic hydrolysis. This study was based on a model composition corresponding to a 34 orthogonal factorial design and employed the response surface methodology (RSM) to optimize the pretreatment and hydrolysis conditions, aiming to attain maximum glucose, xylose and arabinose extraction from cellulose and hemicellulose of biomass. The pretreatment operating conditions considered for optimization, were temperature (60–180 °C), residence time (30–120 min) and sulphuric acid concentration (0.5–5% w w-1). Enzymatic hydrolysis experiments on solid fraction pretreated with diluted acid were performed at a solid concentration of 5% (w v-1, based on dry weight), using 50 mM citrate buffer pH 4.8 with BSA at a concentration of 60 mg g-1 dry biomass. The reaction mixture was incubated at 50 °C for 174 h on an orbital shaker at 150 rpm. Three commercial enzyme preparations (cellulase complex, b-glucosidase and xylanase) were used in enzymatic saccharification. Total carbohydrate content of the initial biomass was 51.25% (in dry mass), of which glucose was the major constituent with 33.59%. Contents of lignin and extractable found in biomass were 24.96% and 15.84%, respectively. In this work, it was possible to extract 93.1% of the sugars present in the olive grove pruning, with pretreatments carried out for 102 min at 156 °C with a sulfuric acid load of 4.09% (w w-1), followed by enzymatic hydrolysis performed for 174 h, with an enzyme loading of 18 PFU, 36 p-NPGU and 36 IU per gram of substrate.