Person:
De Stefano, Lucia

First Name

Lucia

Last Name

De Stefano

URI

https://hdl.handle.net/20.500.14352/75200

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Geodinámica, Estratigrafía y Paleontología

Area

Geodinámica Externa

Identifiers

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Search Results

Now showing 1 - 10 of 42

Learning from experience: a systematic review of assessments of vulnerability to drought
(Natural Hazards, 2016) González Tánago, Itziar; Urquijo, Julia; Blauhut, Veit; Villarroya Gil, Fermín; De Stefano, Lucia
In the last decades, there have been an increasing number of vulnerability studies undertaken in the frameworks of several schools of thought and disciplines. This spur of activity is linked to the growing awareness about the importance of shifting from a crisis-reactive approach to a proactive and preventive risk-management approach to deal with natural disasters. The severity of the impacts that drought provokes worldwide has also contributed to raise awareness about the need to improve its management. In this context, drought vulnerability assessments are the first step in the identification of underlying causes that generate drought impacts. This paper presents a systematic review of past assessments of vulnerability to drought, to enhance the understanding of vulnerability and help orientating future research in this field. Results suggest that there are important geographical and thematic gaps to be filled in the assessment of drought vulnerability. Transparency in the design and validation of results should be improved, while the availability of relevant, reliable, and updated data is still a major constraint at all levels.
An overview of groundwater resources in Spain
(Water, Agriculture and the Environment in Spain: can we square the circle?, 2012) De Stefano, Lucia; Martínez-Cortina, Luis; Chico, Daniel
In Spain, as in most arid and semiarid countries, during the last half century the silent revolution of intensive groundwater use has provided important socio-economic benefits. Nonetheless, traditionally water management has focused on surface water and has paid little attention to groundwater. The European Water Framework Directive (WFD) planning process has resulted in significant advancements in the knowledge of groundwater resources and their use in Spain. However, data on groundwater resources are still partially incomplete and an official countrywide overview of groundwater resources (and their uses) is still not available. At present the estimated groundwater demand is about 7,000 million m3/year, mainly for irrigation purposes. Intensive groundwater use has contributed to the degradation of this strategic resource, which is expected to be partially remediated by the WFD implementation. Previous studies in Andalusia found that in irrigated agriculture groundwater use was economically more productive than surface water. This was attributed to a series of factors, chiefly groundwater resilience to long dry spells, and it was suggested that this could apply also to other regions in Spain. The data presented in this chapter seem to question this former idea, since no clear correlation could be found between the source of water and its apparent water productivity in irrigated agriculture. This is an issue that merits further study, including combining local and country-wide data to refine the calculations.
Managing the Cascading Risks of Droughts: Institutional Adaptation in Transboundary River Basins
(Earth's Future, 2018) Garrick, Dustin E.; Schlager, Edella; De Stefano, Lucia; Villamayor-Tomas, Sergio
Transboundary river basins experience complex coordination challenges during droughts. The multiscale nature of drought creates potential for spillovers when upstream adaptation decisions have cascading impacts on downstream regions. This paper advances the institutional analysis and development (IAD) framework to examine drought adaptation decision‐making in a multijurisdictional context. We integrate concepts of risk management into the IAD framework to characterize drought across its natural and human dimensions. A global analysis identifies regions where severe droughts combine with institutional fragmentation to require coordinated adaptation. We apply the risk‐based IAD framework to examine drought adaptation in the Rio Bravo/Grande—an archetypical transboundary river shared by the United States and Mexico and by multiple states within each country. The analysis draws on primary data and a questionnaire with 50 water managers in four distinct, yet interlinked, “institutional catchments,” which vary in terms of their drought characteristics, socioeconomic attributes, and governance arrangements. The results highlight the heterogeneity of droughts and uneven distribution of their impacts due to the interplay of drought hazards and institutional fragmentation. Transboundary water sharing agreements influence the types and sequence of interactions between upstream and downstream jurisdictions, which we describe as spillovers that involve both conflict and cooperation. Interdependent jurisdictions often draw on informal decision‐making venues (e.g., data sharing, operational decisions) due to the higher transaction costs and uncertainty associated with courts and planning processes, yet existing coordination and conflict resolution venues have proven insufficient for severe, sustained droughts. Observatories will be needed to measure and manage the cascading risks of drought.
Multi-level interactions in a context of political decentralization and evolving water-policy goals: the case of Spain
(Regional Environmental Change, 2018) De Stefano, Lucia; Hernandez-Mora, Nuria
Spain is a highly decentralized country where water governance is a multi-level institutional endeavor requiring effective intergovernmental coordination—in terms of objectives and actions. The paper revisits the evolution of vertical and horizontal intergovernmental interactions in Spain, with a special focus on four interregional river basins. We build on a historical analysis of the evolution of water governance institutions, a mapping of existing interactions over water, careful document analysis, and interviews with selected public officials that are at the interface between the political and the technical spheres. Intergovernmental interaction occurs through different mechanisms that are slowly evolving to adapt to new challenges posed by changing power dynamics and water policy goals. Since the start of political decentralization in 1978, key institutional reforms within and outside of the water sector have opened windows of opportunity for regions to seek new spheres of influence and power. Disputes over water allocation, environmental flows, inter-basin transfers, and even basin boundaries delineation emerge as an expression of a struggle over power distribution between the regions and the central government. The physical and institutional geography of water and diverging visions and priorities (over water and beyond) are among the factors that contribute to shape conflict and cooperation in intergovernmental relations over water.
Lessons from the 2018–2019 European droughts: a collective need for unifying drought risk management
(Natural hazards and earth system sciences, 2022) Blauhut, Veit; Stoelzle, Michael; Ahopelto, Lauri; Brunner, Manuela I.; Teutschbein, Claudia; Wendt, Doris E.; Akstinas, Vytautas; Bakke, Sigrid J.; Barker, Lucy J.; Bartošová, Lenka; Briede, Agrita; Cammalleri, Carmelo; Kalin, Ksenija Cindrić; De Stefano, Lucia; Fendeková, Miriam; Finger, David C.; Huysmans, Marijke; Ivanov, Mirjana; Jaagus, Jaak; Jakubínský, Jiří; Krakovska, Svitlana; Laaha, Gregor; Lakatos, Monika; Manevsk, Kiril; Andersen, Mathias Neumann; Nikolova, Nina; Osuch, Marzena; Oel, Pieter van; Radeva, Kalina; Romanowicz, Renata J.; Toth, Elena; Trnka, Mirek; Trofimova, Iryna; Van Loon, Anne F.; Vliet, Michelle T. H. van; Vidal, Jean-Philippe; Wanders, Niko; Werner, Micha; Willems, Patrick; Živković, Nenad
Drought events and their impacts vary spatially and temporally due to diverse pedo-climatic and hydrologic conditions, as well as variations in exposure and vulnerability, such as demographics and response actions. While hazard severity and frequency of past drought events have been studied in detail, little is known about the effect of drought management strategies on the actual impacts and how the hazard is perceived by relevant stakeholders. In a continental study, we characterised and assessed the impacts and the perceptions of two recent drought events (2018 and 2019) in Europe and examined the relationship between management strategies and drought perception, hazard, and impact. The study was based on a pan-European survey involving national representatives from 28 countries and relevant stakeholders responding to a standard questionnaire. The survey focused on collecting information on stakeholders' perceptions of drought, impacts on water resources and beyond, water availability, and current drought management strategies on national and regional scales. The survey results were compared with the actual drought hazard information registered by the European Drought Observatory (EDO) for 2018 and 2019. The results highlighted high diversity in drought perception across different countries and in values of the implemented drought management strategies to alleviate impacts by increasing national and sub-national awareness and resilience. The study identifies an urgent need to further reduce drought impacts by constructing and implementing a European macro-level drought governance approach, such as a directive, which would strengthen national drought management and mitigate damage to human and natural assets.
A machine learning model to assess the ecosystem response to water policy measures in the Tagus River Basin (Spain)
(Science of the Total Environment, 2021) Valerio, Carlotta; De Stefano, Lucia; Martínez Muñoz, Gonzalo; Garrido, Alberto
Anthropogenic activities are seriously endangering the conservation of biodiversity worldwide, calling for urgent actions to mitigate their impact on ecosystems. We applied machine learning techniques to predict the response of freshwater ecosystems to multiple anthropogenic pressures, with the goal of informing the definition of water policy targets and management measures to recover and protect aquatic biodiversity. Random Forest and Gradient Boosted Regression Trees algorithms were used for the modelling of the biological indices of macroinvertebrates and diatoms in the Tagus river basin (Spain). Among the anthropogenic stressors considered as explanatory variables, the categories of land cover in the upstream catchment area and the nutrient concentrations showed the highest impact on biological communities. The model was then used to predict the biological response to different nutrient concentrations in river water, with the goal of exploring the effect of different regulatory thresholds on the ecosystem status. Specifically, we considered the maximum nutrient concentrations set by the Spanish legislation, as well as by the legislation of other European Union Member States. According to our model, the current nutrient thresholds in Spain ensure values of biological indices consistent with the good ecological status in only about 60% of the total number of water bodies. By applying more restrictive nutrient concentrations, the number of water bodies with biological indices in good status could increase by almost 40%. Moreover, coupling more restrictive nutrient thresholds with measures that improve the riparian habitat yields up to 85% of water bodies with biological indices in good status, thus proving to be a key approach to restore the status of the ecosystem.
Water planning and management after the EU Water Framework Directive
(Water, agriculture and the environment in Spain : can we square the circle?, 2012) De Stefano, Lucia; Hernandez-Mora, Nuria; De Stefano, Lucia; Llamas, Ramón
This chapter provides an overview of the different legal, administrative and economic factors that provide the institutional context for water management in Spain, focusing on the effects of the 2000 European Water Framework Directive (WFD). At present and partially due to the WFD implementation process, the Spanish water sector is experiencing a slow transition from old to new water paradigms. Highlights in this sense are the consideration of the achievement of ecological quality as a primary planning and management objective; an increase in public participation and transparency in water-related decision processes; the economic analysis of water services; and an increased emphasis on water demand management. The achievement of the WFD objectives faces several challenges and uncertainties that are of technical, financial and political nature. However, possibly the key to a successful implementation of the WFD and a real shift of paradigm lays in strengthening the link between land use and water management and in creating institutional structures that facilitate co-responsibility and full cooperation between the central state and the regions, who hold most of the responsibilities on land use management.
Multi-objective optimal design of interbasin water transfers: The Tagus-Segura aqueduct (Spain)
(Journal of Hydrology Regional Studies, 2023) Valerio, Carlotta; Giuliani, Matteo; Castelletti, Andrea; Garrido, Alberto; De Stefano, Lucia
Study region The Tagus-Segura aqueduct (TSA) is a large and strategic water transfer scheme in Spain that connects Entrepeñas and Buendía reservoirs in the Tagus river headwaters to the Segura river basin, a highly stressed Mediterranean area. Study focus The operating rules of the TSA underwent several modifications over the years, and the debate about which are the optimal parameters to meet the interests of the parties involved is still open. We employed Evolutionary Multi-Objective Direct Policy Search to jointly optimize the re-operation of the headwaters dams and the water transfer policy with respect to four conflicting objectives: Tagus and Segura water demands, hydropower production and socioeconomic benefit of the population living on the shores of the headwaters reservoirs. We tested the optimization under the baseline and the 2027 scenario, which foresees an increased environmental flow (EF) in the Tagus river. New hydrological insights for the region The proposed operating rule presents optimized control parameters, a higher degree of freedom and a transferred volume that cyclically varies according to the hydrological stage of the year. In the 2027 scenario, despite the increased EF, the deficit in the aqueduct shows a limited increase compared to the historical solution (+10%), while the storage deficit is strongly reduced (−73%). This benefits the population living on the reservoirs shores and also ensures more stability to the aqueduct functioning.
Analysis of the Evolution of Climatic and Hydrological Variables in the Tagus River Basin, Spain
(Water, 2022) Mezger Lorenzo, Gabriel; De Stefano, Lucia; González del Tánago, Marta
During the second half of the 20th century, several Spanish rivers experienced a decrease in the availability of water resources which coincided with an increase in human water demands. This situation is expected to be exacerbated by climate change. This study analyses the evolution of annual streamflow in 16 sub-basins of the Tagus River basin (Spain) during the 1950–2010 period and its relationship with selected variables. Our main objective is to characterize changes in in-stream flows and to identify what factors could have contributed to them. First, we used non-parametric tests to detect trends in the hydro-climatic series. Then, we analyzed changes in the runoff coefficient and applied regression-based techniques to detect anthropic drivers that could have influenced the observed trends. The analysis revealed a general decreasing trend in streamflow and an increasing trend in air temperature, while trends in precipitation are less clear. Residuals from regression models indicate that the evolution of several non-climatic factors is likely to have influenced the decline in streamflow. Our results suggest that the combination of the expansion of forested areas (a 60% increase from 1950 to 2010) and irrigated land (a 400% increase since 1950) could have played an important role in the reduction of streamflow in the Tagus basin.
Too expensive to be worth it? A methodology to identify disproportionate costs of environmental measures as applied to the Middle Tagus River, Spain
(Journal of Environmental Planning and Management, 2020) Bolinches Quero, Antonio; De Stefano, Lucia; Paredes-Arquiola, Javier
The European Union (EU) Water Framework Directive (WFD) established in 2000 that EU Member States should achieve good status for all their water bodies by 2027 at the latest. The competent authorities are obliged to commit the necessary resources to achieve this goal. In water bodies where the costs are deemed disproportionate, the Directive foresees the definition of exemptions. Two decades after approval of the WFD, however, there is no common method across the EU to evaluate the disproportionality of costs and define the associated exemptions. We propose a methodology based on WFD indicators of water body status and economic variables that are common to all the EU countries. The method uses data that is already available in Eurostat and European Environment Agency databases, thus minimizing data collection costs. The method is applied to the Middle Tagus (Spain), where currently there are several water bodies with declared exemptions for disproportionate costs.