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Linking GMES Space Component to the development of land policies in Outermost Regions - the Azores (Portugal) case-study
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The aim of this study is to assess the potential effectiveness of GMES Space Component Sentinel Missions for land-based environmental policy support in the Azores Autonomous Region (Portugal). Sixteen different types of legal and spatial instruments are currently being applied in this region. Most of them require detailed and accurate Land-use/Land-cover cartography in order to deliver reliable outputs at municipal, island and archipelagic scales. Sentinel-2 Mission products can fulfill these requirements in a cost-effective way. A Spatial Data Infrastructure-based Regional GMES framework is proposed in order to process, assess, validate and integrate this GMES data into the decision support system of Azorean regional land policies.
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... To our knowledge, there is no study on RS vegetation mapping in the Mediterranean insular territories. On the other hand, the vegetation of some oceanic island territories has been established from RS data (Gil & Abadi, 2015;Gil et al., 2011Gil et al., , 2012Gil et al., , 2013Gil et al., , 2014Massetti et al., 2016). Therefore, in addition to the development of vegetation maps of targeted islands, this research aims to assess the utility of using an RF algorithm with high-resolution satellite imagery to classify island plant communities and to determine the ability of high-resolution satellite imagery to accurately map low vegetation cover, which is highly heterogeneous in very small areas. ...
... Considering the large surface area of the Azores and Madeira islands, Gil et al. (2012Gil et al. ( , 2013Gil et al. ( , 2014Gil et al. ( , 2015 used images with different resolutions: Aster of medium resolution 15-90 m, RapidEye 6.5 m spatial resolution, and IKONOS 0.6 m resolution, as well as different satellite image classification techniques. ...
Despite their proximity to the coast, few studies have focused on identifying and mapping the vegetation of Algerian islands and islets. To fill this lacuna, our work, using satellite images and machine learning methods, is mainly aimed at identifying and mapping the main vegetation groups on a few islands, while evaluating the effectiveness of the random forest classifier, which is effectively used in the study of the vegetation of large areas. However, despite the high heterogeneity of their vegetation cover, the use of very high-resolution images (Pléaides and SPOT 6/7), through the fusion bands and derived bands (NDVI), has allowed the elaboration of a fairly precise vegetation map that can be used for the preparation of management and protection plans for these habitats. Our methodological approach revealed very satisfactory results, having allowed the identification of the plant communities inventoried in the field, while showing high accuracy values, ranging from 0.642 for the halophilic group of Asteriscus to 1 for the endemic Chasmophyte group of the Habibas archipelago (Pléiades images). The groups identified from SPOT 6/7 images show accuracy values between 0.67 for the Mediterranean cliff formations on Garlic Islet and 1 for the two formations (shrubby and herbaceous) of the Skikda islands. Our methodological approach, and notwithstanding the great heterogeneity and the very small surface areas of our islands and islets, has led to very satisfactory results, reflected with good overall accuracy and kappa index values (for Pléiades: overall accuracy > 92% and kappa index > 0.90; for SPOT 6/7: overall accuracy > 83% and kappa index > 0.80).
... As islands, most OERs face several obstacles to full development (remoteness, insularity, terrain, climate, economic dependence and narrow range of the goods they produce) which have been mitigated by European Union cohesion policies. Nevertheless, serious environmental issues such as climate change, environmental degradation, loss of biodiversity and proliferation of invasive alien species have to be directly and especially addressed by using the most reliable scientific information and the most advanced technologies (Gil, Fonseca, Lobo & Calado, 2012). Furthermore, the European Commission communication entitled "The Outermost Regions: An asset for Europe" (COM(2008)/642), advocated an alternative approach, focusing on the potential contribution of these regions to overall growth and development in Europe. ...
The Outermost European Regions (OERs) are geographic areas which are part of a European Union Member State, but situated outside continental Europe. All OERs except French Guiana are islands or archipelagos. They face several challenges to full development – remoteness, insularity, terrain and climate constraints, economic dependence and a narrow range of exportable commodities or services. Nevertheless, the European Commission advocates for these regions the assumption of a new paradigm: turning their natural and socioeconomic handicaps into assets. This strategy makes the sustainable development and environmental conservation strategies and policies of OERs especially challenging in scientific, technical and political terms. This Island Studies Journal special section on Sustainable Development and Environmental Conservation in the Outermost European Regions includes five articles that describe, analyse and address directly social-ecological systems’ issues in insular Portuguese and Spanish OERs (Azores and Canaries, respectively). These studies propose novel concepts, strategies and models aiming towards designing and implementing better and more cost-effective sustainability and environmental conservation policies in these remote European regions.
... For the thermal analyses, only nighttime data were used to minimize the effects of topography and surface insolation [25][26][27]44]. It was not possible to use completely cloud-free images in this work due to the significant and almost permanent cloud coverage, which constitutes a relevant challenge for the RS applicability in most small oceanic islands [45], usually resulting in a low number of available images. ...
Current-day volcanic activity in the Azores archipelago is characterized by seismic events and secondary manifestations of volcanism. Remote sensing techniques have been widely employed to monitor deformation in volcanic systems, map lava flows, or detect high-temperature gas emissions. However, using satellite imagery, it is still challenging to identify low-magnitude thermal changes in a volcanic system. In 2010, after drilling a well for geothermal exploration on the northern flank of Fogo Volcano on São Miguel Island, a new degassing and thermal area emerged with maximum temperatures of 100ºC. In the present paper, using the ASTER sensor, we observed changes in the near-infrared signals (15 m spatial resolution) six months after the anomaly emerged. In contrast, the thermal signal (90 m spatial resolution) only changed its threshold value one and a half years after the anomaly was recognized. The results show that wavelength and spatial resolution can influence the response time in detecting changes in a system. This paper reiterates the importance of using thermal imaging and high spatial resolution images to monitor and map thermal anomalies in hydrothermal systems such as those found in the Azores.
... The Mediterranean region constitutes a worldwide hotspot for biodiversity and a challenge for nature conservation and management (Coll et al., 2010;Vogiatzakis et al., 2016;Médail, 2017). Systematic cross-realm conservation planning can serve as an important approach for the maintenance and preservation of their identity as hotspots of endemism (Gil et al., 2012;Fernandes et al., 2015;). However, only a few examples of systematic cross-realm conservation planning studies exist globally (Lagabrielle et al., 2009;Á lvarez-Romero et al., 2011;Makino et al., 2013;Harris et al., 2019;Tsang et al., 2019;Hermoso et al., 2021;Tulloch et al., 2021) and, to our knowledge, only one for the Mediterranean region (Barbosa et al., 2019). ...
In the past years, efforts have been made to include connectivity metrics in conservation planning in order to promote and enhance well-connected systems of protected areas. Connectivity is particularly important for species that rely on more than one realm during their daily or life cycle (multi-realm species). However, conservation plans for the protection of multi-realm species usually involve a single realm, excluding other realms from the prioritization process. Here, we demonstrate an example of cross-realm conservation planning application for the island of Cyprus by taking into account the terrestrial and marine realms and their interface (i.e. coast). Operating within a data-poor context, we use functional connectivity metrics to identify priority areas for the conservation of six multi-realm species, by setting conservation targets simultaneously for the terrestrial and marine realms. MARXAN decision-support tool was used for the identification of the priority areas.
Four scenarios were developed to evaluate the impacts of including connectivity in the prioritization process and the effectiveness of the existing coastal/marine protected areas in the achievement of the conservation targets set for the species. All scenarios considered land and sea anthropogenic uses as surrogate costs to influence the prioritization process.
Our findings show an increase in the area of the reserve network and, therefore, the cost, when connectivity is included, whilst reducing the total boundary length. Furthermore, the current reserve network fails to achieve conservation targets, particularly for the marine part, which has a substantially smaller protection coverage than the terrestrial part.
We conclude that focus should be given in the expansion of the current coastal/marine reserve network following a cross-realm conservation approach. This approach is not only relevant for the conservation of multi-realm species, but also for islandscapes, in particular, where the interdependence between the hinterland and the coast is larger and therefore the magnitude of the impacts generated in one realm and affects the other.
... All this filtering procedure is performed by the algorithm by querying the metadata attributes. Although one of the major drawbacks is the frequent cloud coverage over the archipelago, the high temporal resolution of the image acquisition may mitigate the impact of this issue (Gil et al., 2012). A cloud filter option was added to the application to address this issue (e.g., "Maximum cloud cover: 20 %"). ...
Google Earth Engine App: https://manuferu.users.earthengine.app/view/forestaz |||| Open Source Code available at GitHub: https://github.com/Manuferu/ForestAZ |||| Original article based at https://revistas.inia.es/index.php/fs/article/view/18929 |||| Full citation: Fernández-Urrutia M., & Gil A. (2022). Resource Communication: ForestAz - Using Google Earth Engine and Sentinel data for forest monitoring in the Azores Islands (Portugal). Forest Systems, 31(2), eRC01. https://doi.org/10.5424/fs/2022312-18929
... Importa ainda salientar que as regiões ultraperiféricas apresentam características geográficas e geológicas que as tornam excelentes laboratórios de pesquisa em diversas áreas de estudo, incluindo a das mudanças climáticas. Acresce ainda que a sua biodiversidade e ecossistemas marinhos excecionais são muito promissores em áreas, tais como a inovação em produtos farmacêuticos e agronomia (Gil, Fonseca, Lobo, & Calado 2012). ...
In the European Union (EU) there are nine outermost regions (ORs), among which are the
Autonomous Regional of the Azores (ARA) and the Autonomous Region of Madeira (ARM). The ORs have several specificities that limit their economic and social development, but its strategic importance is significant compared to the Exclusive Economic Zone (EEZ), so it is important to know. The aim of this paper is to deepen the knowledge and describe the evolution of business sector in ARA and ARM. Through a descriptive study using secondary data published by the Serviço Regional de Estatística dos Açores, Direção Regional de Estatística da Madeira and Instituto Nacional de Estatística, it was possible to verify that in the ARA and ARM between 2008 and 2017 there was initially a regression in the number of companies and a later recovery until 2017. In the RAA the total number of companies in 2017 still doesn´t equal the number of
2008. In addition, in both regions, the total numbers of small, medium and large companies in 2017 still do not add up to the figures for 2008. As for the legal form, in the RAA individual companies show a decrease in their expression, while in RAM the trend is reversed. About economic sectors activity, there were some variations over this period namely, in both regions, the construction sector has been decreasing its expression and the accommodation, restaurant and similar sector has increased its expression in relation to the global of companies evidencing a paradigm shift.
... OERs share several geographic similarities and proximity to SIDS and benefit from a particular political status within the European Union (Gil et al., 2012). Due to the support of the States and the European institutions, OERs are privileged areas in which to undertake demonstration projects that can be of high relevance for other small islands. ...
The effects of climate change are global, but small islands are among the most vulnerable places. Local populations on small islands might have a ground-based perspective of the impacts that threaten them. This study was undertaken on Corvo (Azores), where 34% of the residents of both genders and different education levels were surveyed. Here, their understanding of climate change and their perception of its local impacts, the sense of risk, the local areas at risk, the willingness to propose mitigation and adaptation strategies, and the knowledge of regional procedures was analysed. Education played a crucial role in local understanding. The general perception was that the regional policies were insufficient to address climate change issues at the local level. This fact points out that the efforts to mitigate climate change impacts, and the public participation procedures for supporting policy-making, must be significantly increased and improved, in order to reach a real impact on local island communities.
Full citation: Benedicto Royuela, J., Hervías-Parejo, S., Ambros, B., de la Cruz, A. and Gil, A. (2020) ‘Assessing the local perception of climate change in a small island: a case study’, Int. J. Global Warming, Vol. 22, No. 1, pp.30–53. DOI: 10.1504/IJGW.2020.110211
... OERs share several geographic similarities and proximity to SIDS and benefit from a particular political status within the European Union (Gil et al., 2012). Due to the support of the States and the European institutions, OERs are privileged areas in which to undertake demonstration projects that can be of high relevance for other small islands. ...
The effects of climate change are global, but small islands are among the most vulnerable places. Local populations on small islands might have a ground-based perspective of the impacts that threaten them. This study was undertaken on Corvo (Azores), where 34% of the residents of both genders and different education levels were surveyed. Here, their understanding of climate change and their perception of its local impacts, the sense of risk, the local areas at risk, the willingness to propose mitigation and adaptation strategies, and the knowledge of regional procedures was analysed. Education played a crucial role in local understanding. The general perception was that the regional policies were insufficient to address climate change issues at the local level. This fact points out that the efforts to mitigate climate change impacts, and the public participation procedures for supporting policy-making, must be significantly increased and improved, in order to reach a real impact on local island communities.
Full citation: Benedicto Royuela, J., Hervías-Parejo, S., Ambros, B., de la Cruz, A. and Gil, A. (2020) ‘Assessing the local perception of climate change in a small island: a case study’, Int. J. Global Warming, Vol. 22, No. 1, pp.30–53. DOI: 10.1504/IJGW.2020.110211
... Nevertheless, due to climate constraints and the consequent general lack of free-of-charge satellite multispectral remote sensing data (e.g. Landsat) covering most oceanic islands (Gil et al., 2012), few successful examples of land-cover mapping and monitoring are still available for insular territories. In the specific case of the populated Portuguese archipelagos, namely Azores and Madeira, most successful cases were developed by using high/mediumspatial resolution multispectral data and have focused on standard land-cover/land-use and vegetation mapping/assessment (e.g. ...
Full citation: Tassi, A. and Gil, A., 2020. A low-cost Sentinel-2 data and Rao's Q diversity index-based application for detecting, assessing and monitoring coastal land-cover/land-use changes at high spatial resolution. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 1315-1319. Coconut Creek (Florida), ISSN 0749-0208. DOI:10.2112/SI95-253.1
Abstract: Coastal zones in small oceanic islands as the Archipelago of the Azores (Portugal) are very sensitive territories severely threatened by climate change, natural disasters, biological invasions, infrastructure and tourism development, and also agriculture intensification. Land-cover/land-use changes are one of the most relevant indicators for monitoring and assessing coastal spatial planning and management policies in insular territories. This paper describes the application of a low-cost Rao's Q diversity index-based remote sensing tool able to provide a systematic and accurate coastal land-cover/land-use monitoring system in small oceanic islands, using free and open access Sentinel-2 multispectral satellite data and Terceira island (Archipelago of the Azores, Portugal) as the case-study area. Results indicate that about 7% (∼300 hectares) of Terceira Island's coastal zone (∼4290 hectares) have changed their land-cover/ land-use between March 2017 and December 2018 (21 months). Agricultural areas (4.1%), urban areas (2.1%) and bare soil areas (0.6%) are the categories showing more relevant changes.
... The use of optical Earth Observing data may constitute a cost-effective source for estimating AGC stocks in islands' terrestrial carbon pools (Chen et al., 2018;Mutanga, 2015, 2016;Sibanda et al., 2015;Güneralp et al., 2014). The frequent high degree of cloudiness that characterizes many oceanic islands throughout most of the year (Borges et al., 2018;Gil et al., 2012) can be mitigated thanks to the high revisit time capacity of most available satellite-based multispectral sensors with high/very high spatial resolution (for example, RapidEye, Worldview, Planet) and, particularly, by fusing the data obtained from different sensors (Anurogo et al., 2018;Fassnacht et al., 2014;Latifi and Koch, 2012). Island forest assessments are needed on a repeat basis in response to the inherent vulnerability of many these landscapes to rapid changes driven by human land exploitation, natural disasters, biological invasions and sea level rise (Asner et al., 2016). ...
Small islands face environmental issues directly or indirectly related to land cover/land use changes (LCLUC), such as natural hazards, climate change, loss of biodiversity and proliferation of invasive alien species, some of which are caused by direct human exploitation. A Land Cover/Land Use Change (LCLUC) detection approach based on PCA and vegetation indices derived from low cost high-resolution RapidEye multispectral satellite data and available vegetation maps was developed to assess vegetated/forested aboveground carbon stocks and their changes in Madeira Island, Portugal, for the period between December 2009 and August 2011 due to catastrophic events occurred in 2010. During this period, the identified LCLUC revealed a relevant decrease of vegetated areas (especially those dominated by native/endemic communities) substituted by increases of non-vegetated and human-managed vegetated/forested areas. In particular, there was a decrease of 2% of vegetated areas, 30% of which were represented by native/endemic vegetation. The largest and most accurate LCLUC detected were used to estimate changes in aboveground biomass carbon (AGC) stocks. In 2010 more than 25,000 Mg of AGC stocks may have been released. Both relevant LCLUC and AGC stocks depletion in such short period of time may have been strongly enhanced by two catastrophic events that affected Madeira in February (flashflood and landslides) and August 2010 (wildfires). This straightforward and cost-effective methodological approach may be successfully applied in remote territories such as islands or mountainous areas, where the logistic and economic costs associated to periodic and standard airborne remote sensing campaigns for mapping, assessing and monitoring aboveground biomass carbon stocks are generally unaffordable for most decision-makers and land managers in these territories.
Resumo Neste artigo apresentam-se as iniciativas do Instituto Geográfico Português (IGP) relacionadas com produção de cartografia temática de ocupação/uso do solo. Assim, descreve-se a Carta de Ocupação do Solo de 1990 (COS90) e de 2005 (COS2005) e o programa CORINE Land Cover (CLC). Neste artigo apresenta-se também o projecto COSMIC que tem como objectivo o desenvolvimento de metodologias automáticas e expeditas para produção futura de cartografia temática de ocupação/uso do solo com base em imagens de satélite, para os anos entre as actualizações da COS e da carta CLC.
The amount of scientific literature on (Geographic) Object-based Image Analysis - GEOBIA or OBIA in short - has been and still is sharply increasing. The term OBIA is herein used for generic image processing tasks. OBIA researchers with backgrounds in geology, geography or mineralogy are joining forces with colleagues from cell biology, molecular biology, medicine, pharmacy or nanotechnology. More narrowly, GEOBIA's objective is the generation of geographic information (in GIS-ready format), from which new spatial knowledge can be obtained. GEOBIA is a relatively new field of research based upon two major concepts: A) dissecting images or any (pseudo- )continuous multidimensional fields of data, and b) allowing for multiple scales when organizing and utilizing the resulting objects. Analyses of the amount of scientific literature reveal that not only the number of articles is increasing, but that the rate of growth is also noticeably accelerating. Finally, it is discussed whether or not GEOBIA can be considered as an important paradigm in remote sensing. Copyright © (2013) by the American Society for Photogrammetry & Remote Sensing.
The ESA Sentinels will be the first series of operational satellites to meet the Earth observation needs of the European Union-ESA Global Monitoring for Environment and Security (GMES) programme. The pair of Sentinel-3 satellites will provide global, frequent and near-realtime ocean, ice and land monitoring. It continues Envisat's altimetry, the multispectral, medium-resolution visible and infrared ocean and land-surface observations of ERS, Envisat and Spot, and includes enhancements to meet the operational revisit requirements and to facilitate new products and evolution of services. The first launch is expected in 2011/2012.
GMES (Global Monitoring for Environment and Security) which is the European initiative for setting up a wide capability for Earth observation, and is the most ambitious Earth observation program is discussed. GMES has the goal of delivering operational information services for environment and security in six areas: Land, Marine, Atmosphere, Emergency Response, Security and Climate Change. ESA Member States have invested significantly in the set up of GMES by creating and funding the ESA optional GMES Space Component (GSC) Program. The GMES Space Component program will fulfill space-based observation requirements responding to European policy priorities. ESA's function as GSC Coordinator has been described at a high level in several policy documents related to European Space Policy, including several Space Council Orientations, in EU and ESA policy documents and in EC Communications related to GMES.
In this study, the figure condition method was introduced to analyse the accuracy of geometric correction. Figure condition denotes the transformation ability of estimated model parameters for a given transformation model, and it can be used in a geometric correction procedure. To study the figure condition, multisensor satellite images were geometrically corrected using ground control points obtained by different methods. The accuracy of each geometric model was analysed by means of the root mean square error of unit weight and variance–covariance matrix of unknown parameters. Then, an error propagation law was applied to the geometric model in order to investigate the transformation ability of the model parameters and estimate error values of geometric correction for the whole image surface. The results of the research demonstrated that the figure condition can be applied to geometric correction, and error values of the whole study area can be obtained with this new approach without using check points.
Studies are needed to evaluate the ability of present or future SAR data to extract forest attributes over various sites. This study focuses on large unmanaged pine plantations in a vast flat area of ca. 500,000 ha where the tree biomass ranges from 0 to 200 m3/ha corresponding to different forest canopy structures. Results show a good correlation between the backscattering coefficient σ0 (with a 6-dB dynamic range and R2≥.8), the stand timber volume and the stand density. The trend is mainly driven by stand density and different relationships are observed according to age class, which explicitly points out the effects of canopy structure on the backscattering level. Stem volume is derived from the inversion of statistical and semiempirical models, which take these effects into account. Inversion results show that forest biomass attributes can be estimated with relatively small errors commensurate with those achieved by field measurements. Best overall accuracy of ca. 21 m3/ha is reached with the semiempirical model. Error decomposition as a function of age classes shows that, for the same biomass range, errors are higher for old stands than for young stands. Finally, the results indicate that (1) JERS-1 data can be used in an operational way for estimating the biomass of such plantations and (2) it is necessary to take forest stand structure into account. In order to develop reliable biomass-retrieval schemes, future research should focus on examining in a more mechanistic way the relationship between canopy structure and radar signature.