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Language 25 - Ciències de la Terra i l'Espai
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- Multiple Sustainable Practices Are Crucial for Enhancing the Provisioning of Agroecosystem Services Worldwide(2025) Medrano, Luna; Sacristán Moraga, Daniel; Delgado Baquerizo, ManuelFeeding the largest share of the global population, cereal production must enhance sustainability while ensuring food security under global change. Unfortunately, the number of sustainable practices needed to support production, ecosystem services and land conservation remains virtually unknown. We compiled a database of 1570 observations from 349 sites in 57 countries to assess how the number of sustainable practices influences multiple ecosystem services. Our findings reveal that a high number of sustainable practices is crucial for enhancing agroecosystem services such as soil carbon storage, fertility and microbial habitat while supporting yield. Sustainable practices such as crop rotation, limited tillage and incorporation of crop residues were especially important. North America, Eastern Europe and China were particularly dependent on the use of multiple sustainable practices to maintain ecosystem services. Findings underscore the need for integrative strategies employing multiple sustainable practices for mitigating global change, ensuring food security and sustaining ecosystems.
- Deep learning for flood segmentation in remote sensing images(2026) Portalés Julià, Enrique; Gómez Chova, Luis; Mateo García, Gonzalo; Escola de DoctoratEarth observation satellites provide us with unprecedented capacity to monitor our planet at high spatial and temporal resolutions, and have become one of the fundamental tools for responding to flood events, one of the most devastating natural disasters worldwide. Surface water detection from remotely sensed data is a relatively straightforward task, as water has distinctive spectral and geometric properties that interact predictably with current measurement capabilities, such as optical and radar sensors. However, floodwater presents altered versions of these properties, causing well-established water detection methods in the remote sensing literature to perform suboptimally. In the last decade, the growth of data-driven methods has opened new possibilities to develop fast and accurate flood detection methods that can solve these challenges. Therefore, the goal of this Thesis is to advance flood detection capabilities by developing deep learning methods that take advantage of the full spectral, spatial, and temporal dimensions of multisensor satellite data, while grounding them in data-centric principles that ensure their success in real-world scenarios. The first contribution of this Thesis, “Global flood segmentation in optical satellite images”, focuses on advancing flood detection in multispectral data by introducing the WorldFloods v2 dataset and a cloud-aware deep learning model capable of detecting flood extent even in areas covered by semi-transparent clouds. The second contribution, “Multimodal and multitemporal data fusion for flood extent segmentation exploiting Kuro Siwo and WorldFloods Sentinel datasets”, exploits the synergies of multispectral and SAR data, proposing different fusion models that combine their spatiotemporal signals. The third contribution, “Understanding flood detection models across Sentinel-1 and Sentinel-2 modalities and benchmark datasets”, studies how flood detection models trained on single datasets reproduce the biases of these datasets, affecting their generalization capabilities to out-of-distribution floods and datasets. Finally, this Thesis presents results derived from the application of the developed models to large-scale flood events in Australia and Pakistan, providing additional validation of their usefulness for mapping worldwide flood events and quantifying their effects.
- Flood-derived sludge as a reservoir of viable opportunistic pathogens after the October 2024 DANA in Valencia (Spain)(2026) Marina Pérez-Lara; Pablo Ibáñez-Payá; Manuel Ruiz-Platón; Héctor Carmona-Salido; José Juan Mateo; Carmen Amaro; Rubén Salvador-ClavellExtreme flooding events generate large volumes of contaminated sludge that may act as environmental reservoirs of viable microorganisms, yet their capacity to harbour viable bacteria with pathogenic potential remains poorly understood. Following the October 2024 DANA event in Valencia (Spain), flood-derived sludge was collected one month after the episode and analysed using enrichment-based culture, molecular detection, and phenotypic characterization. High loads of culturable bacteria (> 10⁶ CFU·g⁻¹ after enrichment) were recovered, with microbial communities dominated by Enterobacterales, together with Aeromonas spp. and Pseudomonas spp., consistent with contamination from sewage overflows and disturbed urban environments. Culture-based approaches did not yield Vibrio spp.; however, weak qPCR signals for Vibrio vulnificus suggest its presence at low abundance and/or in a viable but non-culturable state. Species-level identification revealed the presence of opportunistic pathogenic taxa, including Escherichia coli, Enterobacter cloacae, Salmonella spp. and Aeromonas spp. Functional characterization showed widespread proteolytic activity and biofilm formation among isolates. In selected strains, haemolytic activity, resistance to human serum, and multidrug resistance were also observed. Notably, one E. coli isolate combined multiple virulence-associated traits and antibiotic resistance, highlighting its potential clinical relevance. Overall, these results demonstrate that flood-derived sludge deposited after extreme rainfall events can function as a reservoir of viable bacteria with pathogenic potential. This study highlights the importance of incorporating microbiological surveillance and risk-oriented approaches into post-flood management strategies under a One Health framework.
- From dynamic control to thermodynamic amplification: The structural redistribution of Iberian precipitation (1950-2024)(2026) Agosta, Eduardo Andrés; Corell, David; Miró Pérez, Juan Javier; Estrela Navarro, María JoséThis study provides a comprehensive evaluation of the hydroclimatic transition of the Iberian Peninsula (1950-2024), characterizing its spatial structure and temporal evolution. By integrating ERA5 atmospheric water balances, high-density station observations, and stepwise regression models, we show evidence that the region is undergoing a structural redistribution of precipitation. The atmospheric water balance indicates a transition toward a moisture-limited sink, characterized by declining surface evaporation and rising atmospheric evaporative demand, while net moisture convergence and total precipitation remain statistically unchanged. Stationlevel analysis robustly validates this volumetric stability (present in 90.5% of the territory) but reveals an underlying zero-sum redistribution: the fractional contribution of extreme precipitation (Rp95) has systematically increased relative to ordinary rainfall (Ro) across 29.6% of the observational network, intensifying along the coasts while ordinary rainfall declines inland (redistribution precipitation-climate scenario). To determine the drivers of this shift, stepwise regressions were applied using the annually aggregated daily frequencies of large-scale circulation patterns (NAO, WeMO, subtropical ridges, and blocks). Results confirm that the stationary frequency of these dynamic drivers successfully explains the long-term stability of total precipitation volume but does not account for the intensification of extremes. The models reveal distinct seasonal mechanisms: while winter extremes exhibit an amplification of dynamic efficiency, autumn extremes (Rp95) remain entirely uncoupled from large-scale circulation. Furthermore, the intensification of these autumn extremes has accelerated significantly in the recent period (1988-2024). Since the dynamic triggers remain stable, these results provide diagnostic evidence highly consistent with thermodynamic amplification. Operating within a moisture-enriched environment, driven by long-term increases in total column water vapor (TCWV), classical synoptic configurations now act as more efficient triggers, thereby enhancing coastal extremes and shifting the Peninsula toward a more extreme, hydrologically volatile regime.
- Detecting problematic beach widths for the recreational use of Mediterranean beaches using Landsat 8 imagery(2019) Cabezas Rabadán, Carlos; Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Rodilla, M.Detecting problematic beach widths for the recreational use of Mediterranean beaches using Landsat 8 imagery
- An efficient protocol for accurate and massive shoreline definition from mid-resolution satellite imagery(2020) Sánchez-García, Elena; Palomar Vázquez, Jesús Manuel; Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Cabezas Rabadán, Carlos; Gómez Pujol, LluísAn efficient protocol for accurate and massive shoreline definition from mid-resolution satellite imagery
- Benchmarking satellite-derived shoreline mapping algorithms(2023) Vos, Kilian; Splinter, Kristen D.; Palomar Vázquez, Jesús Manuel; Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Cabezas Rabadán, Carlos; Kras, Etiënne C.; Luijendijk, Arjen P.; Calkoen, FloriS; Almeida, Luís Pedro; Pais, Daniel; Klein, Antonio H. F.; Mao, yongjing; Harris, Daniel; Castelle, Bruno; Buscombe, Daniel; Vitousek, SeanBenchmarking satellite-derived shoreline mapping algorithms
- Assessing the degradation of polyester fibres from different textiles: A simulation based on laundry release(2026) Soursou, Vasiliki; Campo Velásquez, Julián; Picó García, Yolanda; Thompson, Richard C.; De Falco, FrancescaPolyester (PES) is one of the main synthetic polymers used by the textile industry. The fate of PES microfibres in the environment depends on various parameters including photodegradation and fibres characteristics. In this study, the release and subsequent degradation of PES fibres before and after domestic washing were investigated, using accelerated hydrolytic degradation simulations. Fibres from differently manufactured PES textiles (undyed and dyed fabrics, whole garments) were obtained by cutting the textiles or by washing them in a household washing machine and collecting the fibres released. Degradation simulations of the fibres were performed using an alkaline solution. Hence, this is the first study that employed microfibres directly released during laundry in degradation experiments, to provide a realistic approach. Fibres were analysed in order to compare the effect of the degradation on the differently manufactured textiles, while analyses of the degradation solutions were, also, performed for polyester degradation product quantification and leachates identification. Degradation of PES fibres was evident, with changes in colour, mass loss and PES degradation products increasing throughout the process. Higher fibre loss, double quantity of terephthalic acid (PES product) and higher reduction of vinyl benzoate (PES marker) indicated more substantial degradation of the fibres from garments than those from the fabrics. Non-target analysis of the degradation solutions performed by HPLC-HRMS/MS also indicated that a greater release of leachates including dyes and additives (e.g. 4-nitrophenol, disperse orange 3, phenyldiethanolamine, and acetoacetanilide) occurred during the simulated degradation of the garment fibres, compared to the fabric ones.
- Co-occurrence of microplastics and polycyclic aromatic hydrocarbons in the Júcar River basin (E Spain): The benchmark before 2024's floods(2025) Soursou, Vasiliki; Modugno, Francesca; La Nasa, Jacopo; Giannarelli, Stefania; Andreu Pérez, Vicente; Campo Velásquez, JuliánThe south of the province of Valencia (Spain) is characterised by high flood risk and, in October 2024, Júcar River tributaries were partially responsible for catastrophic floods in the area related to the influence of global warming. The floods carried large amounts of water and sediment and, with them, many pollutants such as microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs). Co-occurrence of MPs and PAHs was investigated in water, sediment and fish samples from the Júcar River basin to set a benchmark of pollution in this flood susceptible area, only four months before the October 2024 catastrophe. Extractions were optimized based on matrix and compound type. Analyses were performed by micro-FTIR, Pyrolysis coupled with Gas Chromatography-Mass Spectrometry (Py-GC-MS) and GC-MS/MS, and ecological and human health risks were, also, estimated for the determined pollutants. Both MPs and PAHs were detected in the majority of samples, with higher concentrations near the river mouth (up to 100 ± 3.8 MPs Kg −1 and 2017.4 ± 107.8 ng g−1 of total PAHs), located close to the metropolitan area of Valencia and its industrial zone. One fish sample (A. alburnus) presented a concentration of 19.97 ± 1.1 μg g−1 of polypropylene (PP) and was contaminated by 11 PAHs, including benzo[a]pyrene (14.2 ± 1.2 ng g−1). Incremental life cancer risk values for MPs and PAHs ranged from 1.7 × 10−6 to 3.1 × 10−4 for all water samples where PAHs were detected, and for the highly polluted fish sample (14.5 × 10−3 and 7.7 × 10−5), indicating potential risk. Principal component analysis (PCA) suggested positive correlation between PP, benzo[a]pyrene and potential cancer risk. This is the first study that provides data on both MPs and PAHs ecological and human health risk assessment in the same environmental samples from a river catchment and establish a benchmark for these pollutants before flooding.
- Benchmarking satellite-derived shoreline mapping algorithms(2023) Vos, Kilian; Splinter, Kristen D.; Palomar Vázquez, Jesús Manuel; Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Cabezas Rabadán, Carlos; Kras, Etiënne C.; Luijendijk, Arjen P.; Calkoen, FloriS; Almeida, Luís Pedro; Pais, Daniel; Klein, Antonio H. F.; Mao, yongjing; Harris, Daniel; Castelle, Bruno; Buscombe, Daniel; Vitousek, SeanBenchmarking satellite-derived shoreline mapping algorithms
- Shoreline Analysis and Extraction Tool (SAET): A new tool for the automatic extraction of satellite-derived shorelines with subpixel accuracy(2023) Palomar Vázquez, Jesús Manuel; Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Cabezas Rabadán, CarlosShoreline Analysis and Extraction Tool (SAET): A new tool for the automatic extraction of satellite-derived shorelines with subpixel accuracy
- Inferring volumetric changes at a shallow lake from subpixel satellite-derived shorelines(2022) Palomar Vázquez, Jesús Manuel; Cabezas Rabadán, Carlos; Castañeda, Carmen; Gracia Prieto, F. Javier; Fernández Sarría, Alfonso; Priego-de-los-Santos, Enrique; Pons-Crespo, Ramón; Pardo Pascual, Josep E.Inferring volumetric changes at a shallow lake from subpixel satellite-derived shorelines
- Characterizing the relationship between the sediment grain size and the shoreline variability defined from Sentinel-2 derived shorelines(2021) Cabezas Rabadán, Carlos; Pardo Pascual, Josep E.; Palomar Vázquez, Jesús ManuelCharacterizing the relationship between the sediment grain size and the shoreline variability defined from Sentinel-2 derived shorelines
- Monitorizando la anchura de las playas mediante imágenes Landsat 8 en costas micromareales mediterráneas(2017) Cabezas Rabadán, Carlos; Pardo Pascual, Josep E.Monitorizando la anchura de las playas mediante imágenes Landsat 8 en costas micromareales mediterráneas
- Characterization of multi-decadal beach changes in Cartagena Bay (Valparaíso, Chile) from satellite imagery(2024) Briceño de Urbaneja, I.; Pardo-Pascual, Josep Eliseu; Cabezas Rabadán, Carlos; Aguirre, Catalina; Martínez, Carolina; Pérez Martínez, Waldo; Palomar Vázquez, Jesús ManuelSandy coastlines are very dynamic spaces affected by a variety of natural and human factors. In Central Chile, changes in oceanographic and wave conditions, modes of inter-annual climate variability such as El Niño Southern Oscillation (ENSO), and extreme events such as earthquakes and tsunamis condition the beach morphology. At the same time, direct human actions alter the arrival of sediments to the coast and their alongshore distribution. Despite the relevance of the beaches for this coastal region and the interesting relationship their morphology has with the aforementioned factors, there is a lack of robust morphological datasets to provide a deep characterization and understanding of the dynamism of the Chilean coast. Based on the information provided by satellitederived shorelines (SDSs) defined by using the SHOREX algorithm, this paper characterizes the morphological changes of Playa GrandeinCartagenaBay(CentralChile)duringtheperiod1985-2019. The shoreline position data are analyzed in the context of changing beach transforming elements, allowing for a better understanding of the changes according to multiple drivers. While some of these factors, such as earthquakes or coastal storms, have a punctual character, changes in wave patterns vary at different time scales, from seasonal to multi-annual, linked to climate phases such as ENSO. Its effects are translated into shoreline erosion and accretion conditioned by the morphology and orientation of the coast while influenced by the availability of sediment in the coastal system. According to that, a conceptual model of the dynamism and redistribution of sediment in the Bay of Cartagena is proposed. The work proves the high utility that the systematic analysis of multi-decadal SDS datasets obtained from the images acquired in the optical by the Landsat and Sentinel-2 offer for beach monitoring and understanding the coastal dynamism.
- Assessment of satellite-derived shorelines automatically extracted from Sentinel-2 imagery using SAET(2024) Pardo Pascual, Josep E.; Almonacid Caballer, Jaime; Cabezas Rabadán, Carlos; Fernández Sarría, Alfonso; Armaroli, Clara; Ciavola, Paolo; Montes, Juan; Souto Ceccon, Paola Emilia; Palomar Vázquez, Jesús ManuelThe definition of the shoreline position from satellite imagery is of great interest among coastal monitoring techniques. Understanding the reality mapped by the resulting shorelines and defining their accuracy is of paramount importance. The assessment described in this paper constitutes a validation of the shorelines obtained by using the novel tool SAET (Shoreline Analysis and Extraction Tool) for automatic shoreline extraction. The resulting shorelines applying the different parameters available in SAET are assessed in 9 test sites with diverse morphology and oceanographic conditions along the Atlantic European and Western Mediterranean coasts. The reference data is obtained along large coastal segments (covering up to about 240 km) from nearly coincident very high-resolution satellite images. Different image processing levels and extraction methods have been tested, showing their key role in the accuracy of shoreline position. When defining the approximate shoreline position the Automated Water Extraction Index for images without shadows (AWEInsh) with a 0 threshold generally constitutes the best segmentation method. In turn, the employment of the mathematical morphological operations of dilation or erosion considerably improves the results in certain coastal typologies. On the contrary, the employment of atmospherically-corrected images has a smaller influence on the accuracy of the SDSs. Results support the idea that the magnitude of the errors is strongly related to the specific coastal conditions- In general, the lowest errors appear in low-energetic microtidal sites, contrary to the energetic and mesotidal coasts with gentle slopes. The shoreline errors range between 3.7 m and 13.5 m RMSE (root-mean-square error) among the different coastal types when selecting the most appropriate extraction parameters. The shoreline position identified with SAET shows a similar or better accuracy to that obtained by other tools.
- Assessing users' expectations and perceptions on different beach types and the need for diverse management frameworks(2019) Cabezas Rabadán, Carlos; Rodilla, M.; Pardo Pascual, Josep E.; Herrera Racionero, PalomaBeach management follows a homogeneous and rigid decision-making process that tries to fulfill expectations assumed from mass tourism without really getting to know the real users' perception. Decisions are usually taken without considering the diversity of values of the beaches, causing high environmental, economic and recreational impacts. In this study, users' profiles, expectations and perceptions have been defined on six Valencian beaches with both different degree of artificialization and sediment type. This has allowed a comparison between semi-natural and urban beaches, and between pebbly and sandy beaches. Differences between beach types have been observed, and a critical analysis of the current management framework and practices has been carried out. Therefore, decision-making should take greater account of users, and actions should be adapted to the diversity of beaches and their particularities, leading to a differential beach management.
- Assessing satellite-derived shoreline detection on a mesotidal dissipative beach(2024) Cabezas Rabadán, Carlos; Almonacid Caballer, Jaime; Benavente, Javier; Castelle, Bruno; Del Rio, Laura; Montes, J; Palomar Vázquez, Jesús Manuel; Pardo Pascual, Josep EliseuThe accuracy and robustness of the shoreline definition from satellite imagery on different coastal types are crucial to adequately characterising beach morphology and dynamics. However, the generic and widespread application of satellite-derived shoreline algorithms is limited by the lack of robust methods and parameter assessments. This work constitutes a quantitative and comprehensive assessment of the satellite-derived waterlines from Sentinel-2 by using the novel SAET tool (Shoreline Analysis and Extraction Tool) on the exposed and mesotidal beach of La Victoria (Cádiz, SWSpain). The diverse parameters available in SAET, such as water indexes, thresholding methods, morphological filters, and kernel sizes, were combined to define water/land interface positions that were compared against coincident video-derived waterlines. Satellite-derived waterline errors are found to be affected by extraction parameters, as well as by the oceanographic and morphological conditions at the time of the image acquisition. The application of a morphological erosion filter on the water mask, which tends to shift the extracted waterline seawards and reduce bias, is the best solution at the dissipative site of La Victoria Beach. Moreover, using a 3 × 3 kernel size consistently shows higher accuracies than a larger kernel. Although there was no parameter combination showing the best skill for all dates, the employment of the Automated Water Extraction Index for images with no shadows (AWEInsh) with a threshold = 0, erosion morphological filter, and 3 × 3 kernel was, overall, the best combination of extraction parameters for this beach (average waterline RMSE of 5.96 m). The combination of the Modified Normalised Difference Water Index (MDNWI) with the Otsu thresholding also led to similar positions of the resulting waterlines and offered good accuracies. In line with other recent research efforts, our work stresses the lack of generic shoreline extraction solutions that can be applied automatically at a global level and the necessity to adapt and validate the extraction methodologies to the different types of coastlines.
- Characterizing beach changes using high-frequency Sentinel-2 derived shorelines on the Valencian coast (Spanish Mediterranean)(2019) Cabezas Rabadán, Carlos; Pardo Pascual, Josep E.; Palomar Vázquez, Jesús Manuel; Fernández Sarría, AlfonsoShorelinepositioncanbeefficientlyextractedwithsubpixelaccuracyfrommid-resolutionsatelliteimageryusing tools as SHOREX. However, it is necessary to develop procedures for deriving descriptors of the beach morphology and its changes in order to become truly useful data for characterizing the coastal dynamism. Anewapproach is proposed based on a spatiotemporal model of the beach widths. Divided into 80 m analysis segments, it offers a robust and detailed characterization of the beach state along large micro-tidal regions, with continuous information through time and space. Geographical and temporal differences can be recognized andmeasured,makingitpossibletostudythebeachresponsebothtogeneralfactors(aswaveconditions)andto punctual anthropic actions (as small sand nourishments). Widths were defined throughout two and a halfyears from 60 shorelines (3.04 m RMSE) covering 50 km of the Gulf of Valencia. Important width contrasts appeared along the study site associated with sediment imbalances motivated by sediment traps and other anthropic actions. Segments too narrow for maintaining therecreational function were located and mapped (16% narrower than 30 m). Short-term width changes appeared linked to storm events, with fast retreatments and slow recoveries. Punctually, even small-magnitude nourishments created perceptible changes in width (12,830 m3 were associated with a 4 m increase). This novel description of the beach state and its changes from Satellite-Derived Shorelines is useful for coastal management, especially considering the global coverage of these free satellite images. It may improve the comprehension of coastal processes as well as monitor human interventions on the coast, helping in the decisionmaking.
- Satellite observations of storm erosion and recovery of the Ebro Delta coastline, NE Spain(2024) Cabezas Rabadán, Carlos; Pardo Pascual, Josep E.; Palomar Vázquez, Jesús Manuel; Roch Talens, Ausiàs; Guillén, J.Storms and extremely energetic events may significantly impact the form and structure of beaches, and so cause erosive processes and coastal damages. Efficient management actions require an up-to-date and accurate knowledge of beach morphological changes, with the shoreline position being a good indicator of such changes. This work proposes the use of the open-source Shoreline Analysis and Extraction Tool (SAET) software for the definition of satellite-derived shorelines (SDSs) from L8 and Sentinel-2 imagery to reveal the shoreline position changes at the beaches of the Ebro Delta, NE Spain. Spatial-temporal models (STMs) of shoreline changes enable a characterisation of how the beaches responded to the storms of 2020. In conjunction with wave data, STMs enable an analysis of the erosive response to storm events, as well as a monitoring of subsequent beach recovery in the short and medium term (<1 year). Results show how Storm Gloria (January 2020, Hs max = 7.62 m) acted as a disruptive event and shifting point in the shoreline trend. As a response to that storm, major erosive pro cesses occurred along the delta that caused an average shoreline retreat of 47 m. A progressive recovery during the spring and summer was mainly associated with periods of low wave energy. Nevertheless, by the end of the year a complete recovery had been achieved for about half of the coast, while the other half showed an average erosion of more than 10 m when compared to the pre-storm situation. Both the erosive and the recovery pro cesses took place unevenly on different sections of the coast, probably dependent on factors such as the orien tation of the beach and the pattern of longitudinal sediment transport along the coast.
