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- Effect of Biochar on Emission of Greenhouse Gases and Productivity of Cardoon Crop (Cynara cardunculus L.)Publication . Barracosa, Paulo; Cardoso, Isabel; Marques, Francisco; Pinto, António; Oliveira, Jorge; Trindade, Henrique; Rodrigues, P.; Pereira, José L.S.Cardoon could be cropped for agro-environmental, industrial, and pharmaceutical purposes. The aim of this study was to assess the effects of biochar on emissions of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4), and productivity of cardoon crop. A pot experiment was run outdoors from April to August 2018, with a cardoon plant per pot. The following four treatments, with four replicates each, were applied: control, soil only; mineral, soil amended with mineral fertilizer (2.5 g N m−2); biochar, soil amended with biochar (1 kg m−2); and mineral+biochar, soil amended with mineral fertilizer (2.5 g N m−2) and biochar (1 kg m−2). The morphological characteristics and biomass production of cardoon plants were evaluated, and the fluxes of N2O, CO2 and CH4 were measured by using the closed chamber technique. The application of biochar combined with mineral reduced N2O emissions by 36% and global warming potential (GWP) by 26% relative to mineral. However, the cumulative CO2 and CH4 emissions as well as yield-scaled GWP were not significantly different among amended soil treatments. Furthermore, the biomass production was increased by 50% by the application of biochar combined with mineral fertilizer relative to mineral. It was concluded that biochar combined with mineral fertilizer is recommended as a pathway mitigation for agro-environmental purposes, because it reduces the global warming potential and could increase the biomass production of cardoon plants.
- Influence of Nitrogen Application and Drip Irrigation on Greenhouse Gas Emissions and Yield of Cardoon Crop (Cynara cardunculus L.)Publication . Barracosa, Paulo; Antunes, Manuela; Marques, Francisco; Pinto, António; Oliveira, Jorge; Trindade, Henrique; Pereira, José L.S.Background: Cardoon is a multi-purpose crop with a wide spectrum of potential applications. Objective: The aim of this study was to assess the effects of nitrogen (N) application and drip irrigation practices on emissions of nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4) and morphological characterization and biomass production of cardoon crop. Methods: The experiment was run under field conditions from April to August 2018. The field experiment was a randomized complete block design with three replications and four treatments: (i) non-amended soil as control (CONTR); (ii) mineral N fertilizer and non-irrigated (NITRO); (iii) non-fertilized and drip irrigation (IRRIG); and (iv) mineral N fertilizer and drip irrigation by fertigation (FERTI). The fluxes of N2O, CO2 and CH4 were measured by the closed chamber technique and the morphological characteristics and yield of cardoon plants were evaluated per treatment. Results: Results showed that the N2O emissions and global warming potential were not significantly different among the application of mineral N fertilizer itself or by drip fertigation with an emission rate of 0.5% of N applied and -6,8 t CO2-eq. ha-1. The characteristics related to biomass production did not differ significantly (p>0.05) between amended treatments although numerically higher in IRRIG treatment. Conclusion: It was concluded that the application of mineral N fertilizer itself or drip fertigation had no significant effect on N2O emissions and global warming potential. Additionally, the plant growth, including biomass production, increased due to drip irrigation, but not significantly.
- Instrumental methods as strategic supporting tools for systematic biochemical analysis of serra da estrela sheep milk.Publication . Oliveira, Jorge; Lemos, Carlota; Brito, Manuel; Pinto, António; Coutinho, Rui Coutinho; Barracosa, Paulo; Coelho, Catarina; Dinis, RuiSerra da Estrela sheep crude milk is mandatory for the PDO Serra da Estrela (SE) cheese production. The production system implies the need for systematic knowledge of the values of useful matter (fat and protein) to produce cheese. The knowledge of somatic cell count (SCC) allows to predict the mammary health status of ewes as well as make decisions on the use of crude milk for human consumption, through its transformation into cheese. The need for simple, fast and reliable methodologies for the determination of this parameters is fundamental for the sustainability of this productive sector through milk recording procedure for animal genetic evaluation, as well for the previous analysis of the bulk milk, before the process of elaboration of the PDO SE cheese. Two sets of milk samples were collected: 50 individual samples of Serra da Estrela ewes’ milk from 2 farms for analysis of SCC and 53 samples of Serra da Estrela ewes’ milk (16 individual samples and 37 samples of bulk milk) for analysis of fat and protein contents (Fat% and Prot%). Duplicates of samples were simultaneously analyzed by reference and instrumental methodologies (DCC De Laval optical reader and FT-NIR MasterTM from Büchi) as reliable alternatives for parameters evaluation for the SE sheep milk. The results showed a significant agreement between the pairs of values (type of methodologies) for all parameters, with correlations between 0.925 (Prot%) and 0.960 (SCC) (p<0.001). The linear regressions for the pairs of data of the three parameters studied presented a strong adjustment (with the coefficients of determination between 0.856 and 0.921). The findings showed that both instrumental methodologies applied can be used as alternative to count somatic cells and evaluate fat and protein contents of SE sheep milk and will be useful as strategic measuring devices for milk farmers and cheesemakers.
- Influence of cardoon flower (cynara cardunculus L.) and flock lactation stage in PDO Serra da Estrela cheesePublication . Fogeiro, Élia; Barracosa, Paulo; Oliveira, Jorge; Ferreira Wessel, DulcineiaSerra da Estrela (SE) cheese is one of the most appreciated Portuguese cheeses, being produced only from raw ewe's milk, cardoon flower and salt. Cardoon takes part in two important processes in cheese production-coagulation and proteolysis-contributing to its unique features. Furthermore, milk chemical characteristics change during the milking season, being another factor that account for the high variability of cheese attributes. Therefore, the purpose of this work is to study the influence of cardoon flower (commercial, 6 M and 3 M) and flock lactation stage (November 2018, February and April 2019) in the final characteristics of SE cheese. The parameters analysed were moisture, protein, fat and salt contents, texture and colour. Results showed that flock lactation stage has the highest influence in all the studied characteristics, corresponding the early stages of lactation to the most protein-rich and low-fat cheeses. Cardoon flower affects mainly fat and rind colour. This study allows us to conclude that seasonal changes in ewe's milk have a considerable impact in cheese attributes, and that although cardoon type had a more restrained effect, when used with expertise it may help adjust cheese sensory characteristics in order to obtain a final product that matches consumer acceptability requirements.