Browsing by Author "Oliveira, Sérgio"
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- 2002 - Ano internacional das montanhasPublication . Rodrigues, Luísa; Trindade, Jorge; Oliveira, Sérgio
- Applicaton of Digital Shoreline Analysis System (DSAS) for analyzing sandy coast dynamics in Essaouira, MoroccoPublication . Khouz, Abdellah; Trindade, Jorge; Oliveira, Sérgio; El Bchari, F.; Bougadir, BlaidCoastlines change research plays a crucial role in understanding the evolution and ensuring effective risk management. This is essential for minimizing impacts on the environment and society. Our study aims to assess the coastal dynamics of sandy systems in Essaouira. By employing advanced techniques such as DSAS and GIS, we aim to analyze shoreline changes, erosion rates, and susceptibility to sand movement. The insights gained from our investigation into the sandy coastal system will provide valuable input for making informed decisions regarding territorial management.
- Assessment of landslide susceptibility in the rocky coast subsystem of Essaouira, MoroccoPublication . Oliveira, Sérgio; Khouz, Abdellah; Trindade, Jorge; Elbchari, Fatima; Bougadir, Blaid; Garcia, Ricardo; Jadoud, Mourad
- Assessment of subsidence and collapse hazards using electrical resistivity tomography: case study of Ida Ouazza salt mine, Essaouira province - MoroccoPublication . Khouz, Abdellah; Trindade, Jorge; El Bchari, Fatima; Bougadir, Blaid; Oliveira, Sérgio; Garcia, Ricardo; Ibouh, H.; Jaffal, H.; Ikirri, M.; Laftouhi, N.; Elachgar, H.; Jadoud, Mourad
- Coastal slope instability and susceptibility mappingPublication . Trindade, Jorge; Oliveira, Sérgio; Khouz, Abdellah; Garcia, Ricardo; Ebchari, Fatima; Bougadir, Blaid; Chaibi, Mohamed
- Combining the weights of evidence model, the Strahler/Shreve hydrographic model, and the HEC-RAS analysis for the assessment of flood susceptibility in Essaouira Province, MoroccoPublication . Khouz, Abdellah; Trindade, Jorge; Oliveira, Sérgio; Santos, Pedro; El Bchari, Fatima; Bougadir, Blaid; Garcia, Ricardo; Reis, Eusébio; Jadoud, Mourad; Silva, Andreia
- Flood susceptibility assessment through statistical models and HEC-RAS analysis for sustainable management in essaouira province, MoroccoPublication . Khouz, Abdellah; Trindade, Jorge; Santos, Pedro Pinto; Oliveira, Sérgio; Bchari, Fatima El; Bougadir, Blaid; Garcia, Ricardo; Reis, Eusébio; Jadoud, Mourad; Saouabe, Tarik; Rachidi, SaidFloods are natural disasters that often impact communities living in low-lying areas in the northern and central parts of Morocco. In this study, our aim was to create a flood susceptibility map using three methods; the hierarchy process (AHP) frequency ratio model (FR) and the weights of evidence (WoE) model. We extensively examined the area identified by these approaches using a hydraulic analysis software called HEC-RAS (version 6.3.1). Our analysis focused on the Essaouira watersheds in Morocco, where we identified around 197 flood locations. Out of these, we randomly selected 70% for modeling purposes while the remaining 30% were used for validation. Ten factors that influence floods were considered, such as slope, elevation, proximity to rivers, drainage density, stream order, land use patterns, rainfall data, lithology (permeability level) index (TWI), and curvature. We obtained these factors from data sources. Finally, we generated a flood susceptibility map and evaluated its accuracy by calculating the area under the curve (AUC). The validation results confirmed that all three models were robust and effective with an AUC of 90. Moreover, the research uncovered a trend of vulnerability with the most susceptible area being in close proximity to the city of Essaouira along the Oued Ksob. A detailed analysis using HEC-RAS was conducted at this identified location, pinpointing the village of Diabat as highly exposed. These findings hold significance for flood management, empowering decision makers, scholars, and urban planners to make informed choices and implement strategies that can minimize the impact of floods in susceptible regions while minimizing potential damages.
- Landslide susceptibility assessment in rocky coast subsystem of Essaouira coastal area - MoroccoPublication . Khouz, Abdellah; Trindade, Jorge; Oliveira, Sérgio; El Bchari, Fatima; Bougadir, Blaid; Garcia, Ricardo; Jadoud, MouradIn recent decades, multiple researchers have produced landslide susceptibility maps using different techniques and models, including the information value method, which is a statistical model that is widely applied to various coastal environments. This study aimed to evaluate the susceptibility to landslides in the Essaouira coastal area using bivariate statistical methods. In this study, 588 distinct landslides were identified, inventoried, and mapped. They primarily result from the observation and interpretation of different data sources, namely, high-resolution satellite images, aerial photographs, topographic maps, and extensive field surveys. The rocky coastal system of Essaouira is located in the middle of the Atlantic coast of Morocco. The study area was split into 1534 cliff terrain units 50 m in width. For training and validation purposes, the landslide inventory was divided into two independent groups: 70% for training and 30% for validation. Twenty-two layers of landslide-conditioning factors were prepared, namely elevation, slope angle, slope aspect, plan curvature, profile curvature, cliff height, topographic wetness index, topographic position index, slope over area ratio, solar radiation, presence of faulting, lithological units, toe lithology, presence and type of cliff toe protection, layer tilt, rainfall, streams, land-use patterns, normalized difference vegetation index, lithological material grain size, and presence of springs. The statistical relationship between the conditioning factors and different landslide types was calculated using the bivariate information value method in a pixel and in the elementary terrain units-based model. Coastal landside susceptibility maps were validated using landslide training group partitions. The receiver operating characteristic curve and area under the curve were used to assess the accuracy and prediction capacity of the different coastal landslide susceptibility models. Two methodologies, considering a pixel-based approach and using coastal terrain units, were adopted to evaluate coastal landslide susceptibility. The results allowed for the classification of 38% of the rocky coast subsystem with high susceptibility to landslides, which were mostly located in the southern part of the Essaouira coastal area. These susceptibility maps will be useful for future planned development activities as well as for environmental protection.
- Methodology for sea level rise hazard assessment in the exposed coastal zone of the Portuguese mainlandPublication . Trindade, Jorge; Reis, Eusébio; Rocha, Jorge; Santos, Pedro Pinto; Garcia, Ricardo; Oliveira, Sérgio; Silva, Andreia; Pinheiro, Samuel; Cuervas-Mons, JoseFuture scenarios of sea level rise in Portugal are expected to put at risk sensitive areas from a natural and urban point of view. This research proposes a methodology for the assessment of sea level rise Hazard zones using the evaluation of permanent and episodic components as important factors to predict flooding and coastal erosion hazards for the Shared Socioeconomic Pathway 1, 2 and 5 scenarios, in 2040, 2070 and 2100.
- Metodologia para a definição de áreas inundáveis pela subida do nível do mar em litorais expostos, na costa portuguesaPublication . Trindade, Jorge; Zêzere, José Luís; Reis, Eusébio; Rocha, Jorge; Santos, Pedro; Gercia, Ricardo; Oliveira, Sérgio; Pereira, Susana; Silva, Andreia