IGOT - Artigos em Revistas Internacionais
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- 100 Years of land-use and land-cover data: what has been the effect of spatial planning in coastal land-use and land-cover change?Publication . Faria de Deus, Raquel; Tenedório, José António; Pumain, Denise; Rocha, Jorge; Pereira, MargaridaThe Sustainable Development Goals require us to rethink spatial planning policies’ effectiveness. This article proposes a reproducible method for assessing the effect of past planning practices and simulating future land-use and land-cover (LULC) changes with a Cellular Automata model. The originality of our approach is to systematically compare observed changes in LULC with the planning rules in force over almost a century of evolution. A quasi-exhaustive database was constructed at a very fine spatial resolution for the municipality of Portimão (Southern Portugal), including the location and changes of LULC categories, and the planning rules of the corresponding time period on nine dates between 1947 and 2018. The quantified measurement of the actual effect of planning rules enables us to identify other determinants of the evolution. Findings reveal that the policies established by the local government—which aimed to foster well-planned comprehensive urban areas—were not as effective as intended. The quantified discrepancies between planning recommendations and observed evolution help to simulate which LULC scenarios could be designed to reach the expected result in future planning policies. Our assessment method could be applied in other urban and tourist regions where land artificialization exerts strong pressure on the environment.
- 1421: o ano em que a China descobriu o mundoPublication . Oliveira, Francisco Roque DeA principal referência deste livro é a figura do almirante Zheng He (c. 1371-c. 1435), o célebre navegador chinês de origem muçulmana que, entre 1405 e 1421, foi encarregado pelo imperador Yongle (r. 1403-1424) de conduzir seis grandes expedições oficiais aos mares da Ásia do Sueste, a Ceilão, à Índia, ao Golfo Pérsico, ao Mar Vermelho e à costa oriental de África compreendida entre, pelo menos, a actual Somália e Melinde.
- 500-year temperature reconstruction in the Mediterranean Basin by means of documentary data and instrumental observationsPublication . Camuffo, Dario; Bertolin, C.; Barriendos, M.; Dominguez-Castro, F.; Cocheo, C.; Enzi, S.; Sghedoni, M.; della Valle, A.; Garnier, E.; Alcoforado, Maria Joao; Xoplaki, E.; Luterbacher, J.; Diodato, N.; Maugeri, M.; Nunes, M. F.; Rodriguez, R.The paper reports the main results of the EU project Millennium in the Mediterranean area over the last 500 years. It analyses a long series of temperature from Portugal, Spain, France, Italy and Greece. The series are obtained by combining indices from documentary sources from AD 1500 to the onset of regular instrumental observations. There is an ongoing discussion regarding the proper way of combining documentary and instrumental data and how to translate accurately the conventional indices from − 3 to + 3 into modern units, i.e. degree Celsius. This paper produces for the first time a number of early instrumental observations, in some cases (i.e. Italy and France) covering 350 years, including thereby the earliest regular observations after the invention of the thermometer. These Mediterranean data show that anomalous temperatures usually had only a locally limited effect, while only few extreme events had a widespread impact over the whole region, such as the summer of 2003. During the period from 1850 to the present day, the Mediterranean temperature anomaly was close to the Northern Hemisphere in spring and summer, while it was warmer in autumn and winter. Compared with the long-term instrumental records (i.e. 1655 onwards), the recent warming has not exceeded the natural past variability characterized by heating–cooling cycles with no significant long-term trends.
- Acacia saligna (Labill.) H. Wendl in the Sesimbra County: invaded habitats and potential distribution modelingPublication . Gutierres, F.; Gil, A.; Reis, Eusébio; Lobo, A.; Neto, Carlos; Calado, H.; Costa, J. C.The aim of this study is to establish the spatial pattern of colonization and spread of Acacia saligna by predictive modeling, susceptibility evaluation and to perform a cost-effective analysis in two sites of community importance (Fernão Ferro/Lagoa de Albufeira and Arrábida/Espichel) in the Sesimbra County. The main goal is to increase the knowledge on the invasive process and the potential distribution of the Acacia saligna in Sesimbra County, namely in the Natura 2000 sites. The Artificial Neural Networks model was developed in Open Modeller to predict the potential of occurrence of A. saligna, and is assumed to be conditioned by a set of limiting factors that may be known or modeled. The base information includes a dependent variable (present distribution of specie) and several variables considered as conditioning factors (topographic variables, land use, soils characteristics, river and road distance), organized in a Geographical Information System (GIS) database. This is used to perform spatial analysis, which is focused on the relationships between the presence or absence of the specie and the values of the conditioning factors. The results show a high correspondence between higher values of potential of occurrence and soils characteristics and distance to rivers; these factors seem to benefit the specie’ invasion process. According to the conservation value of each cartographic unit, related to natural habitats included in Habitats Directive (92/43/EEC), the coastal habitats (2130, 2250 and 2230) were the most susceptible to invasion by A. saligna. The predicted A. saligna distribution allows for a more efficient concentration and application of resources (human and financial) in the most susceptible areas to invasion, such as the local and national Protected Areas and the Sites of Community Importance, and is useful to test hypotheses about the specie range characteristics, habitats preferences and habitat partitioning
- Accessibility to primary health care in low-density regions: case study: NUTS III, Baixo Alentejo, PortugalPublication . Freitas, Carlos; Marques Da Costa, NunoThis study diagnosed the situation regarding the physical accessibility of the resident population to primary health care, based on the characteristics of the population served, their spatial distribution in the territory, based on space-time analysis. Thus, bearing the different means of transport available and the specific features of a low-density territory, we considered several mobility profiles under analysis, and selected the Baixo Alentejo as the study area. In methodological terms, besides using the location of primary health facilities and their areas of influence, the use of the road network and its restrictions, we selected the use the new 1x1 km grid, recently implemented throughout the EU (European Union), instead of using the statistical units or administrative boundaries. Its advantages allow overcoming some of the issues of the usual base cartography. The final results can be divided into two groups: conclusions related to the methodologies used and conclusions related to the accessibility of primary health care equipment in the study area.
- Accessibility to urgent and emergency care services in low-density territories: the case of Baixo Alentejo, PortugalPublication . Ferreira, Rita; Marques da Costa, Nuno; Marques Da Costa, EduardaAccess to health care is a sensitive issue in low population density territories, as these areas tend to have a lower level of service provision. One dimension of access is accessibility. This paper focuses on measuring the accessibility to urgent and emergency care services in the Portuguese region of Baixo Alentejo, a territory characterized by low population density. Data for the calculation of accessibility is the road network, and the methodology considers the application of a two-level network analyst method: time-distance by own mean (car or taxi) to the urgent care services and the time distance to emergency services as a way to get assistance and to go to urgent care services. While urgent care accessibility meets the requirements stipulated in the Integrated Medical Emergency System’s current legislative framework, the simulation of different scenarios of potential accessibility shows intra-regional disparities. Some territories have a low level of accessibility. Older adults, the poorly educated, and low-income population, also have the lowest levels of accessibility, which translates into dually disadvantageous situation since the potential users of emergency services are most likely to belong to this group of citizens.
- Accurate determination of surface reference data in digital photographs in ice-free surfaces of Maritime AntarcticaPublication . Pina, Pedro; Vieira, Goncalo; Bandeira, Lourenço; Mora, CarlaThe ice-free areas of Maritime Antarctica show complex mosaics of surface covers, with wide patches of diverse bare soils and rock, together with various vegetation communities dominated by lichens and mosses. The microscale variability is difficult to characterize and quantify, but is essential for ground-truthing and for defining classifiers for large areas using, for example high resolution satellite imagery, or even ultra-high resolution unmanned aerial vehicle (UAV) imagery. The main objective of this paper is to verify the ability and robustness of an automated approach to discriminate the variety of surface types in digital photographs acquired at ground level in ice-free regions of Maritime Antarctica. The proposed method is based on an object-based classification procedure built in two main steps: first, on the automated delineation of homogeneous regions (the objects) of the images through the watershed transform with adequate filtering to avoid an over-segmentation, and second, on labelling each identified object with a supervised decision classifier trained with samples of representative objects of ice-free surface types (bare rock, bare soil, moss and lichen formations). The method is evaluated with images acquired in summer campaigns in Fildes and Barton peninsulas (King George Island, South Shetlands). The best performances for the datasets of the two peninsulas are achieved with a SVM classifier with overall accuracies of about 92% and kappa values around 0.89. The excellent performances allow validating the adequacy of the approach for obtaining accurate surface reference data at the complete pixel scale (sub-metric) of current very high resolution (VHR) satellite images, instead of a common single point sampling.
- Active aging awareness and well-being among older adults in PortugalPublication . Costa, Andreia; Henriques, Joana; Alarcão, Violeta; Henriques, Adriana; Madeira, Teresa; Virgolino, Ana; Sousa, Joana; Feteira-Santos, Rodrigo; Arriaga, Miguel; Rocha, Jorge; Nogueira, PauloObjective: This study aims to assess the active aging awareness of older adults in mainland Portugal and their levels of overall well-being and to identify social and health-related factors. Methods: A cross-sectional study was conducted with a representative sample of 613 older adults, aged 65 or older, who participated in the PROKnos – Knowing Social Prescribing needs of the elderly study in Portugal. The questionnaire consisted of the Active Ageing Awareness Questionnaire and the World Health Organization – Five Well-Being Index, as well as sociodemographic, economic, and health status questions. Correlation coefficients, t-tests for independent samples, and one-way ANOVA were used to explore potential associations between variables. Results: The active aging awareness levels were significantly higher for women (p = 0.031), and those who were younger (p = 0.011), more educated (p < 0.001), had a better financial situation (p < 0.001), and had better health (p < 0.001). The same pattern was found for well-being, except in relation to gender, as men had higher levels (p = 0.016). These variables were found to be correlated. Discussion: Even though active aging is an important strategy to implement, it is indispensable to consider the perceptions and conditions that need to be in place before that. This study reveals that several social and health-related factors are associated with well-being and active aging awareness, as well as the differences between groups that exist in mainland Portugal in relation to that. This emphasizes how vital it is to address social inequalities in active aging efforts, which are not necessarily uncovered when only considering actual active aging measures.
- Active layer and permafrost thermal regimes in the ice-free areas of AntarcticaPublication . Hrbáček, Filip; Oliva, Marc; Hansen, Christel; Balks, Megan; O'Neill, Tanya Ann; de Pablo, Miguel Angel; Ponti, Stefano; Ramos, Miguel; Vieira, Gonçalo; Abramov, Andrey; Kaplan Pastíriková, Lucia; Guglielmin, Mauro; Goyanes, Gabriel; Francelino, Marcio Rocha; Schaefer, Carlos; Lacelle, DenisIce-free areas occupy <0.5% of Antarctica and are unevenly distributed across the continent. Terrestrial ecosystem dynamics in ice free areas are strongly influenced by permafrost and the associated active layer. These features are the least studied component of the cryosphere in Antarctica, with sparse data from permanent study sites mainly providing information related to the ground thermal regime and active layer thickness (ALT). One of the most important results of the International Polar Year (IPY, 2007/08) was an increase in ground thermal regime monitoring sites, and consequently our knowledge of Antarctic permafrost dynamics. Now, 15 years after the IPY, we provide the first comprehensive summary of the state of permafrost across Antarctica, including the sub-Antarctic Islands, with analyses of spatial and temporal patterns of the dominant external factors (climate, lithology, biota, and hydric regime) on the ground thermal regime and active layer thickness. The mean annual ground temperatures of the active layer and uppermost part of the permafrost in Antarctica remain just below 0 °C in the warmest parts of the Antarctic Peninsula, and were below −20 °C in mountainous regions of the continent. The ALT varies between a few cm in the coldest, mountainous, parts of the Transantarctic Mountains up to >5 m in bedrock sites in the Antarctic Peninsula. The deepest and most variable ALTs (ca. 40 to >500 cm) were found in the Antarctic Peninsula, whereas the maximum ALT generally did not exceed 90 cm in Victoria Land and East Antarctica. Notably, found that the mean annual near-surface temperature follows the latitudinal gradient of −0.9 °C/deg. (R2 = 0.9) and the active layer thickness 3.7 cm/deg. (R2 = 0.64). The continuous permafrost occurs in the vast majority of the ice-free areas in Antarctica. The modelling of temperature on the top of the permafrost indicates also the permafrost presence in South Orkneys and South Georgia. The only areas where deep boreholes and geophysical surveys indicates discontinuous or sporadic permafrost are South Shetlands and Western Antarctic Peninsula.
- Active layer dynamics in three topographically distinct lake catchments in Byers Peninsula (Livingston Island, Antarctica)Publication . Oliva, Marc; Hrbacek, Filip; Ruiz-Fernández, Jesús; de Pablo, Miguel Ángel; Vieira, Goncalo; Ramos, Miguel; Antoniades, DermotTopography exerts a key role in controlling permafrost distribution in areas where mean annual temperatures are slightly negative. One such case is the low-altitude environments of Maritime Antarctica, where permafrost is sporadic to discontinuous below 20–40 m asl and continuous at higher areas and active layer dynamics are thus strongly conditioned by geomorphological setting. In January 2014 we installed three sites for monitoring active layer temperatures across Byers Peninsula (Livingston Island, South Shetland Islands) at elevations between 45 and 100 m. The sites are situated in lake catchments (lakes Escondido, Cerro Negro, and Domo) that have different geomorphological and topographical conditions. Our objective was to examine the role of topography and microclimatic conditions in determining the active layer thermal regime in order to identify the factors that control geomorphic processes in these lake catchments. At each site a set of loggers was installed to monitor air temperature (AT), snow thickness (SwT) and soil temperature (ST) down to 80 cm depth. Mean annual air temperatures (MAAT) showed similar values in the three sites (−2.7 to −2.6 °C) whereas soil temperatures showed varying active layer thicknesses at the three catchments. The ground thermal regime was strongly controlled by soil properties and snow cover thickness and duration, which is influenced by local topography. Geomorphological processes operating at the lake catchment scale control lacustrine sedimentation processes, and both are dependent on the combination of topographical and climatic conditions. Therefore, the interpretation of lake sediment records from these three lakes requires that soil thermal regime and snow conditions at each site be taken into account in order to properly isolate the geomorphological, environmental and climatic signals preserved in these lake records.