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Percorrer CCMAR por Objetivos de Desenvolvimento Sustentável (ODS) "11:Cidades e Comunidades Sustentáveis"
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- Impact of climate change on portuguese marine coastal environmentsPublication . Pinto, Miguel; Bueno-Pardo, Juan; Marta-Almeida, Martinho; Leitão, FranciscoThe potential impacts of climate change on marine habitats were assessed using RCP4.5 and RCP8.5 projections of environmental parameters that included sea surface temperature (SST), pH, salinity, planktonic productivity (PP) and current strength (CS). The analysis was conducted separately for three distinct oceanographic regions of the Portuguese coastline (North, Centre and South) up to the middle of the century. Temporal trends in environmental variables were assessed using time series analyses. Overall, changes expected up to the middle of the century include increasing SST and PP, decreasing pH and salinity, and slight increases in CS. Spatial–temporal analyses revealed high present–future environmental overlay for most environmental variables. However, changes in individual environmental variables cumulatively resulted in statistically significant changes in environmental similarity. Still, the projected changes are not expected to exceed ecological thresholds, above which they would be likely to alter species’ habitat suitability or to result in species distribution shifts. Anomaly analyses suggest that present–future shifts do not surpass 1/5 (pH, PP, CS) or 2/3 (salinity) of the unit, regardless of projection and area, while SST anomalies ranged from −1.1 ◦C to 1.1 ◦C. Compared to IPCC large-scale predictions for Atlantic/Mediterranean regions, the intensity of shifts on the Portuguese coast may be lower.
- Impact of climate change on portuguese marine coastal environmentsPublication . Pinto, Miguel; Bueno-Pardo, Juan; Marta-Almeida, Martinho; Leitão, FranciscoThe potential impacts of climate change on marine habitats were assessed using RCP4.5 and RCP8.5 projections of environmental parameters that included sea surface temperature (SST), pH, salinity, planktonic productivity (PP) and current strength (CS). The analysis was conducted separately for three distinct oceanographic regions of the Portuguese coastline (North, Centre and South) up to the middle of the century. Temporal trends in environmental variables were assessed using time series analyses. Overall, changes expected up to the middle of the century include increasing SST and PP, decreasing pH and salinity, and slight increases in CS. Spatial–temporal analyses revealed high present–future environmental overlay for most environmental variables. However, changes in individual environmental variables cumulatively resulted in statistically significant changes in environmental similarity. Still, the projected changes are not expected to exceed ecological thresholds, above which they would be likely to alter species’ habitat suitability or to result in species distribution shifts. Anomaly analyses suggest that present–future shifts do not surpass 1/5 (pH, PP, CS) or 2/3 (salinity) of the unit, regardless of projection and area, while SST anomalies ranged from −1.1 °C to 1.1 °C. Compared to IPCC large-scale predictions for Atlantic/Mediterranean regions, the intensity of shifts on the Portuguese coast may be lower.
- A millennium-scale iberian margin chronology validates the 1755 Lisbon tsunami record and reveals faro recordPublication . Abrantes, Fatima; Domingues Gomes, Sandra; Salvado, Marta; Magalhães, Vitor; Salgueiro, Emilia; Drago, Teresa; Cordeiro, Lívia; Naughton, FilipaThis work presents new data and several age–depth reconstructions based on distinct approaches to improve previously published age models for sedimentary sequences collected on the Iberian Margin middle shelf: PO287 6-1B, 2G (Porto); PO287 26-1B, 3G, and D13902 (Lisbon); and POPEI VC2B (Algarve). The new age models are constructed using radiocarbon dates calibrated with the IntCal20 calibration curve and smooth-spline regressions from the CLAM (non-Bayesian) and Bacon (Bayesian) models. A comparison of the age–depth models generated by the different approaches shows that, beyond the distinct solutions produced by CLAM and Bacon for each site, the differences between the two methods are inconsistent across sites. Furthermore, neither model yielded reliable results for the discontinuous sedimentary sequence with reworked older sediments and a hiatus. In this specific case, the “classical” linear regression (best-fit) approach appears to yield the results that enable intercomparison across all sequences. This exercise confirms the record of the 1755 earthquake and tsunami in the Lisbon core splice and a potential record of the same event in the Eastern Algarve, although the collected data indicate a more distal or lower-energy wave deposit.
- Spatiotemporal patterns, loads, and risks of microplastics in the stormwater system of a subtropical coastal cityPublication . Du, Aolei; Xu, Youxiang; Luo, Yutang; Jian, Qiying; Li, Yanjun; Zhan, Ziying; Qiu, Sizhe; Kam, Chon Wa; Chan, Tin-Chak; Huang, Tsz-Yin; Power, Deborah Mary; Zhang, KaiUrban stormwater runoff is a critical pathway for microplastics (MPs) to enter marine ecosystems, posing a significant threat. However, systematic studies on spatiotemporal patterns, loads, and risks of MPs in stormwater systems, particularly in subtropical coastal cities, remain limited. This study characterized MPs in Macao's stormwater drains across seasons, using density separation, H2O2 digestion, stereomicroscopy, and μ-FTIR analysis to investigate their abundance and distribution. MPs were ubiquitous across all sample sites, with abundance ranging from 0.86 to 53.03 n/L. Irregular shaped fragments (56.78 ± 0.13.80%) and the color black (38.44 ± 7.47%) were dominant, and the most common polymers were Polyethylene terephthalate (39.55 ± 16.63%), polypropylene (23.05 ± 18.15%), and polyethylene (9.52 ± 8.87%). While abundance of MPs was higher in the wet season, no significant seasonal variation was found. MP characteristics varied significantly with land use. The concentration range of MPs was estimated to be from 2.86 ± 0.38 to 3145.94 ± 766.74 μg/L, with an overall mean of 454.68 ± 572.20 μg/L through the mass concentration models. The daily MP emission load into the receiving water was estimated to range from 8.29 × 103 to 3.09 × 108 particles per day or 2.66 to 10,365.23 g/day. MP risk was high (Polymer Hazard Index/Potential Ecological Risk Index: III/V) due to hazardous polymers, with spatiotemporal variations further observed from fluctuating water flow erosion. Correlation analysis revealed that MP abundance showed a significant negative correlation with dissolved oxygen and a positive correlation with antecedent rainfall. These findings identify stormwater drains as a key MP conduit, influenced by rainfall and land use, calling for targeted management in urban coastal areas.
- Tracking tourism waves: insights from automatic identification system (AIS) data on maritime–coastal activitiesPublication . Ramos, Jorge; Drakeford, Benjamin; Costa, Joana; Madiedo Camelo, Ana Maria; Leitão, FranciscoAbstract: The demand for maritime–coastal tourism has been intensifying, but its offerings are sometimes limited to a few activities. Some of these activities do not require specific skills or certifications, while others do. This study aimed to investigate what type of activities are carried out by tourism and recreational vessels in the coastal area of the central Algarve (Portugal). To this end, data from the automatic identification system (AIS) of recreational vessels was used to monitor and categorise these activities in a non-intrusive manner. A model (TORMA) was defined to facilitate the analysis of AIS data and relate them to five independent variables (distance from the coast, boat speed, bathymetry, seabed type, and number of pings). The results of the analysis of more than 11 thousand hourly AIS records for passenger, sailing, and charter vessels showed that the 14 most regular ones had strong seasonal patterns, greater intensity in summer, and spatial patterns with more records near some coastal cliffs. This study provides valuable information on the management of motorised nautical activities near the coast and at sea, contributing to more informed and effective tourism regulation and planning.