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- Avaliação da ameaça de erosão hídrica na ilha da Madeira - PortugalPublication . Coutinho, Miguel de Azevedo; Oliveira, Rodrigo Proença de; Antunes, Carla Rolo; Caetano, Cláudia TomásNa estimativa da erosão hídrica na ilha da Madeira aplicou-se a Equação de Wischmeier. Recorreu-se a relações para estimar a erosividade (R); foi adequado o Índice Modificado de Fournier e relação IMF/R. cartografada a erosividade os restantes parâmetros resultaram da metodologia. IMF varia entre 81.0–465.0 mm. A equação R = 1.365 IMF1.408 estima a erosividade anual precipitação, com dados de Funchal-Observatório, sul de Portugal e valores da literatura, obtendo-se R ≈ 2 964 MJ mm h−1 ha−1 ano−1, variando entre 660- 8515. Erosão média é 28 t ha−1 ano−1, excedendo 100 em >4.9% da área. A ameaça de erosão adveio da divisão do volume de solo dos horizontes mobilizáveis, pela erosão anual. O resultado -número de anos- que ocorre a perda do solo de cobertura. Apesar do tempo para esgotamento do solo, ser >20 000 anos, a ameaça de erosão, alta e muito alta, é relevante. Estas ameaças (depleção <100 anos) ocorrem em 263 km2 (35.6%); na ameaça muito alta (depleção em <10 anos) a área é ≈40 km2 (5.4%). Encostas com declives muito elevados estão associadas a ameaças altas (ou muito altas). Efetuouse a análise da precipitação 20 de Fevereiro, obtendo-se um período de retorno superior a 100 anos.
- Using participatory mapping to Foster Community-Based disaster risk reduction in Forest Fire-Prone Areas: the case of Monchique in PortugalPublication . Partidário, Maria; Saad, Guilherme; Monteiro, Margarida B.; Dias, Joana; Martins, Rute; Ramos, Isabel Loupa; Ribeiro, Henrique; Teixeira, Miguel; Costa Freitas, M. B.; Antunes, CarlaLocal knowledge and communities’ active role in disaster risk areas are recognized in the literature as key conditions to better understand risks, enhance adaptive capacities and foster local resilience. A participatory action research project in forest fire-prone areas in Monchique, Portugal, is aligned with the literature and adopts participatory mapping as a method that can bring evidence to the importance of local knowledge and communities’ agency. In the BRIDGE Project, different types of knowledge are integrated, triggering local/collective agency and fostering a forest fire community-based disaster risk reduction (CBDRR) approach. An innovation laboratory (InnoLab) provides the space for dialogue and knowledge sharing for different actors that manage forest territories. In the InnoLab, participatory mapping is used as a method to engage landowners where risk factors and local vulnerabilities were identified. Their active engagement enabled a collective perception in the assessment of vulnerability and led to the identification of strategic measures for risk reduction. This paper shares the process and outcomes of this participatory mapping, highlighting the benefits of a community approach and the importance of local knowledge and practices as recognized in the literature. It also reveals how the active role of local stakeholders can help drive a CBDRR process.
- A composite indicator to measure sustainable water use in Portugal: a compromise programming approachPublication . Costa Freitas, M. B.; Xavier, António; Fragoso, Rui; Antunes, CarlaClean water is an important resource for maintaining human life, economic activities, and ecosystems' survival. Nevertheless, its irregular distribution and occasional scarcity lead to the need to promote its sustainable use. To assess the current situation and the dynamics of sustainable water use, it is crucial to identify the main factors affecting it and to propose monitoring indicators. This paper develops an approach based on compromise programming to analyse water use sustainability at the municipal level, with a methodology that comprise a framework designed in five steps: 1 - indicators' choice; 2 - indicators's weights; 3 - definition of sustainability rankings with the application of a compromise programming approach; 4- application of a GIS analysis; 5 - identification of the main factors affecting sustainable water use. As a first result, the consensus weights of the chosen indicators were defined, indicating that the most important internal factors affecting sustainable water use are safe water, the percentage of housing served by water supply and water distributed by inhabitant. Then sustainability rankings at the municipality level were defined considering these factors. Finally, it was possible to conclude that tourism activity, income level, and young age population have a significant negative effect on sustainable water use, and municipal revenue has a positive effect. Irrigated farming shows a non-significant negative effect on sustainable water use. Population density, elderly population and education level did not show the expected effects on sustainable water use.
- Best management practices for the transition to a water-sensitive city in the South of PortugalPublication . Rodrigues, Miguel; Antunes, CarlaThe uncertainty that arises from future environmental and climatic challenges requires new approaches towards urban water management in Mediterranean cities. In this work, an urban water cycle (UWC) strategy based on the best management practices (BMPs) of water-sensitive urban design (WSUD) is proposed for the transition of a coastal city in the south of Portugal into a water-sensitive city (WSC), in line with the Municipal Strategy for Climate Change Adaptation of Loulé (EMAAC of Loulé). The city’s watershed was identified using the ArcMap Hydrology toolset with geospatial data provided by Loulé’s Municipal Council Operational Unit for Adaptation to Climate Change and Circular Economy (UOACEC). A broad characterisation of the study area was conducted, identifying existing resources to further develop a SWOT (strengths, weaknesses, opportunities, threats) analysis. The Hydrology toolset outputs, precipitation events records, and survey results were used to identify flood-prone areas. The opportunities and threats identified were further used to develop the transition strategy, which is focused on critical areas identified and supported by BMPs, including source control, attenuation, treatment and infiltration measures, permeable pavements, rainwater harvesting systems, and bioretention basins. The approach is designed to increase the city’s resilience to climate extremes, as well as community engagement towards UWC management.
- A compromise programming approach for assessing territorial biophysical suitability: a Case StudyPublication . Xavier, António; Ferreira da Silva da Costa Freitas, Maria de Belém; Rolo Antunes, Carla MariaLand-use fragmentation is an important issue for land management and rural development. For the last few decades, the relationship between mankind and land has become more dynamic though the traditional cadastral system has been slow in responding to the changing needs of society. Associated with land-use fragmentation, there are different sizes of land parcels with different biophysical characteristics that will dictate different land management decisions, and, in many countries, it is a problem that constitutes a challenge for correct land management. This article proposes a compromise programming approach for determining the biophysical potential of land parcels. This approach was implemented in Loul & eacute; municipality, Portugal, in more than 50,000 parcels. Results were promising since the approach was able to build a ranking of parcels that have different biophysical conditions, proving that this approach is relevant and interesting for land management.
- Restoring and rehabilitating watercourses in the Ria Formosa Nature Park (Algarve): intervention principles, processes and techniquesPublication . Fonseca dos Santos, Maria Amélia; Rolo Antunes, Carla Maria; Batista, DesidérioThe core objective of this article is to contribute towards defining a project methodology for rehabilitating fluvial ecosystems in strongly humanized Mediterranean landscapes. To achieve this objective, interrelated with the management and maintenance of these landscapes, we took into consideration the theory and the praxis that frame interventions in watercourses experiencing situations of risk. This article spans these two core, interwoven facets, approaching both the theoretical research and the applied research undertaken within the scope of proposals for rehabilitating five watercourses in Eastern Algarve. The project approach to the restoration of the ecological corridors associated with the downstream sections of the Cacela, Canada, Tronco, Bela-Mandil streams, and the Seco River thus accounted for the shortage and irregularity in the distribution of precipitation and the torrential regime characterizing the region in conjunction with the high level of artificialism displayed by these fluvial systems. Under the auspices of the project process, the aforementioned watercourses were perceived as dynamic, complex, open, and multi-functional socio-ecological systems with a role and importance in ensuring the biological balance and physical stability of the coastal plain and the Ria Formosa lagoon system. The project concept was rooted in a strategy based on intervention flexibility, taking into account a balance between the rehabilitation of natural values and resources and the presence of human activities. Hence, in the rehabilitation proposals developed, the materials applied were entirely natural (plants, wood, and stone), with recourse to technical-scientific concepts and procedures drawn from the fields of Landscape Architecture and Biophysical Engineering.
- Beyond cadaster: landowners and land fragmentation—insights from a case studyPublication . Ferreira da Silva da Costa Freitas, Maria de Belém; Teixeira, Miguel; Rolo Antunes, Carla Maria; César Ribeiro, Henrique; Partidário, Maria do RosárioLand management is a relevant problem in rural areas all over the world, conditioning the planning decisions and the applicability of planning instruments. This study evaluates the limitations of cadastral data in representing land fragmentation and management patterns in wild-fire-prone landscapes, using Alferce (Portugal) as a case study with broader international relevance. Similar challenges—fragmented ownership, incomplete land registries, and increasing wildfire risk—affect many regions worldwide, particularly across the Mediterranean basin and other fire-prone rural landscapes. A mixed-methods approach combines cadastral data with field data from 23 landowners producing two datasets: cadaster-only and ownership-enhanced. Fragmentation is assessed using Simmons and Januszewki indices, supported by spatial analysis (Kernel Density and Moran’s I). Results show that cadastral data alone significantly overestimates fragmentation. While parcel-based analysis suggests a highly fragmented landscape, incorporating ownership information reveals more aggregated management structures. The 23 landowners manage 1247 ha (≈13% of the area), forming a “keystone” group with strong potential for coordinated land management and fire prevention. Higher fragmentation is associated with population centers. These findings demonstrate that cadastral units do not reflect functional management units and considerations about property fragmentation are biased by the lack of information about the owners, a key theoretical contribution with implications beyond Portugal. For policymakers, integrating ownership data and targeting key land managers can improve land use planning and wildfire mitigation and, overall, the sustainability of the territory. Despite limitations (small sample), the approach is transferable to other regions facing similar structural constraints.