Browsing by Author "Veiga-Pires, C."
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- A ciência-cidadã ao serviço da mudança: o exemplo do projeto A Minha PraiaPublication . Gouveia, Licínia; Lourenço, Carla R.; Afonso, João; Freitas, Ricardo; Veiga-Pires, C.; Reis, Emanuel; Rodrigues, Miguel; Gomes, Tiago; Rodrigues, Luís; Mira, Sara; Ferreira, Hélder; Pinto, Andreia; Vaz, Paula; Drago, Teresa; Soares, Isabel; Ramos, AnaVencedor da 1ª edição do Orçamento Participativo Portugal (2017), A Minha Praia é um projeto de monitorização ambiental que pretende sensibilizar para a conservação do meio marinho e estimular hábitos de consumo responsáveis, através de ações de ciência cidadã e civismo ambiental.
- A ciência-cidadã ao serviço da mudança: o exemplo do projeto A Minha PraiaPublication . Gouveia, Licínia; Lourenço, Carla; Afonso, João; Freitas, Ricardo; Veiga-Pires, C.; Reis, Emanuel; Rodrigues, Miguel; Gomes, Tiago; Rodrigues, Luís; Mira, Sara; Ferreira, Hélder; Pinto, Andreia; Vaz, Paula; Drago, Teresa; Soares, Isabel; Ramos, AnaVencedor da 1ª edição do Orçamento Participativo Portugal (2017), A Minha Praia é um projeto de monitorização ambiental que pretende sensibilizar para a conservação do meio marinho e estimular hábitos de consumo responsáveis, através de ações de ciência cidadã e civismo ambiental.
- A Instituição através de uma caderneta de cromosPublication . Veiga-Pires, C.; Guerra, Liliana; Baptista, Elina; Reis, Emanuel; Dias, Filipe; Martins, Ana Paula; Vintém, DanielaExistem variadas formas de comunicação para dar a conhecer uma instituição, que seja ela privada ou pública. Considerando por um lado a sua missão e por outro lado o seu pequeno orçamento, o Centro Ciência Viva do Algarve (CCVAlg) optou por desenvolver um projeto que permitisse criar um produto educativo e lúdico e ao mesmo tempo transmitir a imagem de uma instituição promotora da transferência de conhecimento científico. Nesse sentido e de forma a apresentar um produto multidisciplinar que aproveitasse as especificidades da região, foi decidido desenvolver um projeto sobre a Ria Formosa, que além de oferecer um ambiente natural de grande riqueza também permite abordar temas como a economia, a história, a arquitetura ou ainda a geologia, entre outros. De seguida, foi necessário encontrar não só os parceiros que possuam os conhecimentos científicos que se pretendia transmitir mas igualmente o parceiro que desenvolvesse o suporte que alberga-se o projeto. Os parceiros científicos foram naturalmente surgindo, tratando-se de entidades que são reconhecidas pelo seu trabalho no sistema lagunar de ilhas barreiras da Ria Formosa, como é o caso do Parque Natural da Ria Formosa (PNRF-ICNF), da Universidade do Algarve (UALG) e da Associação RIAS. Quanto ao parceiro técnico, o CCVAlg teve a sorte de ser contactado pela empresa COLARA que desenvolve cadernetas digitais de cromes, produtos que respondem perfeitamente ao objetivo de associar uma vertente lúdica à vertente educativa. Assim nasceu a caderneta digital de cromes sobre a Ria Formosa que integra i) o conhecimento científico; ii) a divulgação científica; iii) a educação não formal e interativa e iv) a comunicação institucional. O lançamento da caderneta terá lugar na 1a semana da Ria Formosa organizada pelo Instituto de Conservação da Natureza e da Floresta que decorrerá de 4 a 8 de Abril nos 5 concelhos que abrigam a Ria Formosa.
- Algarve: a study case for global vs regional climatic changes in mid latitude estuaries during the HolocenePublication . Veiga-Pires, C.; Mestre, Nélia; Moura, Delminda; Luis, Joaquim; Boski, T.Located at the extreme southwestern end of the Iberian Peninsula, in the South of Portugal, the Algarve province is bordered to the north by the Alentejo province, to the east by the Guadiana River, and to the west and south by the Atlantic Ocean. Its coastal region can be divided into two different sectors: the eastern sector, which is mainly made of barrier island and lagoon system named the Ria Formosa, and the western sector mainly represented by clastic and carbonated cliffs. In each sector, we sampled long and short sedimentary cores (ca. 30m and 3m, respectively) in two different estuaries. Therefore, the different sedimentary records obtained from the four estuaries should permit to identify global vs. west-eastern regional climatic changes through the observation of several proxies. Two of these proxies are sediment color and magnetic susceptibility, which have been acquired every five centimeters along core depth, using the Colortron II spectrophotometer and SM-20 magneto-susceptometer, respectively. Sediment surfaces of short cores were also digitized using the Mustek 1200 A3 PRO Scanner. Furthermore, short cores have been sampled every five centimeters along depth in order to analyze the sediment for its major and minor elements content, its organic carbon content, and its granulometry and mineralogy. Some shell fragments have also been sampled and sent for radiocarbon radiometry or AMS dating, allowing therefore constructing some absolute chronologies for the several cores. Some relative chronologies based on digital color profiles are also being used in order to correlate sedimentary sequences between cores. All the cores are mainly composed of clay, with the existence of soil horizons at the top of the cores and frequent sand layers towards their base. Several element profiles along depths are compared, namely those regarding Sr, Ca, F, Ba, Al and Ti, as well as their ratios. First results indicate that geochemical and color data allow to identify similar sequences from west to east probably related to major climate episodes. Although, pronounced differences in mineralogy and accumulation rates from on site to another are probably due to differences, respectively, in the geochemistry of the drainage basin substratum and in the flow rate of the rivers, and therefore to local precipitation. We acknowledge FEDER and OE that financed this study through the Portuguese Foundation for Science and Technology (FCT) (POCTI/CTA/39733/2001).
- An attempt to develop spectrophotometry as a proxy for sedimentary studies in estuarine environmentsPublication . Veiga-Pires, C.; Mestre, Nélia; Moura, Delminda; Luis, Joaquim; Boski, T.In deep-sea sediment studies, reflectance has been used as a proxy for high vs. low productivity intervals for several years. This value of the white-black scale is obtained through the use of spectrophotometers when using the CIE Lab color system, which also gives values on green-red and blue-yellow scales. In estuarine/continental sediment studies, color data are still often based on Munsell Table which does not allow to obtain numeric and continuous data and which is biased by the observer’s choice.
- An attempt to use CIE Lab digital colour to study sediment profiles from the Alvor estuary, South PortugalPublication . Veiga-Pires, C.; Mestre, Nélia; Moura, Delminda; Martins, H.; Boski, T.The study of estuarine sedimentary records is of great interest for paleo-environmental and paleo-climatologic reconstructions, because they represent environments that are sensitive to sea level and climatic variations, and also because they are characterized high sedimentary rates. However, due to the price and time needed to analyze the geochemical composition of sediments, it is very difficult to obtain profiles with a high resolution needed toanswer present scientific problems. In the present work, we report results obtained by applying solid-state spectrophotometry on cores from the Alvor's estuary (Algarve), which allows acquiring almost continous, high resolution, digital colour profiles. CIE Labcolour data, obtained with a Colortron spectrophotometer in there cores, were to geochemical sediment characteristics using multivariate statistical analyses.(...)
- An attempt to use color as a tool for high resolution correlations between estuarine sedimentary cores from Algarve (Portugal)Publication . Mestre, Nélia; Veiga-Pires, C.Nowadays, paleoenvironmental and climatological researches focus on studying shortterm climatic changes and one of the more sensitive environments for recording those short-term climatic variations are the high sedimentation rate of coastal regions. Accordingly, 4 estuaries from the Algarve region, south of Portugal, have been cored in order to study sedimentary and climatic variations during recent times (c.a. 5000 yrs). For this purpose, we applied sampling and analytical techniques from deep-sea studies, allowing the acquirement of almost continuous data profiles, as the color data obtained with the spectrophotometer Colortron.
- An open source geophysical software for studying speleothem growth bands and comparing with a reference curve: MironePublication . Veiga-Pires, C.; Coelho, Catarina; Moura, Delminda; Luis, JoaquimSpeleothem growth bands are commonly referred as one of the parameters that are used for paleoclimate reconstructions. Accordingly, this work presents a new tool for detecting these bands based on the gray-scale image of the speleothem using the Mirone open source geophysical software. This program has initially been developed for working on georeferenciated images for geophysical studies, as for instance for recognizing paleomagnetic inversions from deep-sea sediments. This recognition based on gridded images is very similar to what is needed for the recognition and detection of speleothem growth bands.
- Assessing land–ocean connectivity via submarine groundwater discharge (SGD) in the Ria Formosa Lagoon (Portugal): combining radon measurements and stable isotope hydrologyPublication . Rocha, Carlos; Veiga-Pires, C.; Scholten, Jan; Knoeller, Kay; Gröcke, Darren R.; Carvalho, Liliana; Aníbal, J.; Wilson, JeanNatural radioactive tracer-based assessments of basin-scale submarine groundwater discharge (SGD) are well developed. However, SGD takes place in different modes and the flow and discharge mechanisms involved occur over a wide range of spatial and temporal scales. Quantifying SGD while discriminating its source functions therefore remains a major challenge. However, correctly identifying both the fluid source and composition is critical. When multiple sources of the tracer of interest are present, failure to adequately discriminate between them leads to inaccurate attribution and the resulting uncertainties will affect the reliability of SGD solute loading estimates. This lack of reliability then extends to the closure of local biogeochemical budgets, confusing measures aiming to mitigate pollution. Here, we report a multi-tracer study to identify the sources of SGD, distinguish its component parts and elucidate the mechanisms of their dispersion throughout the Ria Formosa – a seasonally hypersaline lagoon in Portugal. We combine radon budgets that determine the total SGD (meteoric + recirculated seawater) in the system with stable isotopes in water (δ2H, δ18O), to specifically identify SGD source functions and characterize active hydrological pathways in the catchment. Using this approach, SGD in the Ria Formosa could be separated into two modes, a net meteoric water input and another involving no net water transfer, i.e., originating in lagoon water re-circulated through permeable sediments. The former SGD mode is present occasionally on a multi-annual timescale, while the latter is a dominant feature of the system. In the absence of meteoric SGD inputs, seawater recirculation through beach sediments occurs at a rate of ∼ 1.4 × 106 m3 day−1. This implies that the entire tidal-averaged volume of the lagoon is filtered through local sandy sediments within 100 days ( ∼ 3.5 times a year), driving an estimated nitrogen (N) load of ∼ 350 Ton N yr−1 into the system as NO3−. Land-borne SGD could add a further ∼ 61 Ton N yr−1 to the lagoon. The former source is autochthonous, continuous and responsible for a large fraction (59 %) of the estimated total N inputs into the system via non-point sources, while the latter is an occasional allochthonous source capable of driving new production in the system.
- Atmospheric halogen and acid rains during the main phase of Deccan eruptions: magnetic and mineral evidencePublication . Font, Eric; Fabre, Sébastien; Nedelec, A.; Adatte, T.; Keller, G.; Veiga-Pires, C.; Ponte, J.; Mirão, José; Khozyem, H.; Spangenberg, J. E.; Gerta Keller, Andrew C. Kerr,Environmental changes linked to Deccan volcanism are still poorly known. A major limitation resides in the paucity of direct Deccan volcanism markers and in the geologically short interval where both impact and volcanism occurred, making it hard to evaluate their contributions to the mass extinction. We investigated the low-magnetic-susceptibility interval just below the iridium-rich layer of the Bidart (France) section, which was recently hypothesized to be the result of paleoenvironmental perturbations linked to paroxysmal Deccan phase 2. Results show a drastic decrease of detrital magnetite and presence of scarce akaganeite, a hypothesized reaction product formed in the aerosols derived from reaction of a volcanic plume with water and oxygen in the high atmosphere. A weathering model of the consequences of acidic rains on a continental regolith reveals nearly complete magnetite dissolution after ~31,000 yr, which is consistent with our magnetic data and falls within the duration of the Deccan phase 2. These results highlight the nature and importance of the Deccan-related environmental changes leading up to the end- Cretaceous mass extinction.