Francisco J. Alcalá

Spanish National Research Council | CSIC · Department of Desertification and Geoecology

The Miocene evolution of the External Rif Zone (NW Africa Plate) was determined through the multidisciplinary analysis of fourteen successions. The updated stratigraphic framework shows how Miocene sediments rest on the Cretaceous-Paleogene terrains through unconformity surfaces, whereas it rests with sedimentary continuity in two sectors. After re...

Climate change, coupled with adaptive human actions, will affect water resource access and availability for environmental requirements. Hydrological modelling is an effective strategy for forecasting climate and human impacts on water resources. Modelling tools are advised for sparse-data mountainous basins intended to supply densely populated urba...

Groundwater is limited and its sustainable use is peremptory if we are to preserve dependent ecosystems and human supplies [...]

The protection of groundwater resources in coastal aquifers is an increasingly important issue worldwide. To establish threshold values and remediation objectives, it is essential to know the natural background concentrations of relevant ions in groundwater. The rationale is to define the Natural Background Level (NBL) of chemical species determine...

This paper introduces a methodology based on Python libraries and machine learning k-Nearest Neighbors (KNN) algorithms to create an interactive 3D HTML model (3D_Vertical_Sections_Faults_LRD.html) that combines 2D grain-size KNN-prediction vertical maps (vertical sections) from which syn-sedimentary faults and other features in sedimentary porous...

The increasing industrial pulp production has led to a negative growth of the associated solid wastes, thus making necessary alternative ways of handling them in suitable sanitary landfills to minimize adverse effects on the environment and well-being of people. Solid waste treatment prior to its disposal is a target to minimize pollution of the na...

Designing sustainable management strategies in groundwater-dependent socio-economic systems in areas with scarce water resources and protected wetlands is a challenging issue. The high vulnerability of these systems to droughts will be exacerbated even further under future climate change (CC) and socio-economic scenarios. A novel integrated bottom-...

In a previous paper, the authors implemented a machine learning k-nearest neighbors (KNN) algorithm and Python libraries to create two 3D interactive models of the stratigraphic architecture of the Quaternary onshore Llobregat River Delta (NE Spain) for groundwater exploration purposes. The main limitation of this previous paper was its lack of rou...

Morocco is a water-scarce developing country with a growing marketable agro-food industry, where untreated or insufficiently treated wastewater represents less than 1% of the irrigation water and treated wastewater reuse is virtually nil. The Government of Morocco is planning to increase the volume of treated wastewater reuse for irrigation agricul...

In accordance with the Sustainable Development Goals of the United Nations, the Environmental Impact Assessment (EIA) is the main management tool used to identify and prevent the impact of productive activities on the environment and human health and promote compensation measures. Metallic mining is the main productive sector in Chile. In 2021, Chi...

Groundwater degradation is a major issue on an increasingly hot and thirsty planet. The problem is critical in drylands, where recharge rates are low and groundwater is the only reliable resource in a context of water scarcity and stress. Aquifer depletion and contamination is a process of desertification. Land Degradation Neutrality is regarded as...

The hydrological situation of rivers, the fundamental driving force of river ecosystems, has continued to change due to the impact of human activities on water environments. Intra- and inter-annual variation also causes alterations in morphology, water quality, flora, and fauna in riparian zones. In this study, we present a novel approach to assess...

The k-nearest neighbors (KNN) algorithm is a non-parametric supervised machine learning classifier; which uses proximity and similarity to make classifications or predictions about the grouping of an individual data point. This ability makes the KNN algorithm ideal for classifying datasets of geological variables and parameters prior to 3D visualiz...

Groundwater degradation is a global problem linked to irrigation agriculture and aggravated by climate change. In drylands, where aquifer recharge is low, irrigation has emerged as an engine of economic growth. This problem falls under the paradigm of desertification, as it fits the definition of this complex problem in that the degradation of dryl...

This paper introduces a Python application for visualizing the 3D stratigraphic architecture of porous sedimentary media. The application uses the parameter granulometry deduced from borehole lithological records to create interactive 3D HTML models of essential stratigraphic elements. On the basis of the high density of boreholes and the subsequen...

The Environmental Impact Assessment (EIA) is a legal and administrative tool aimed to identify, predict, and interpret the impact of a project or activity on the environment and human health. The EIA also evaluates the accuracy of the predictions and audits the effectiveness of the established preventive measures. Regarding the sanitation sector, e...

The book collects nine original contributions in the field of integrated geophysical methods for shallow aquifers characterization and modelling. The first contribution introduces the following eight ones into the overall framework of the topic. The second contribution integrates seismic and electrical techniques to define geometry and identify tra...

Groundwater research is increasingly using geophysical prospecting surveys for aquifer characterization in different hydrogeological environments. They have become a part of the holistic strategy to define aquifer geometry and some transient groundwater features, which are necessary data to implement numerical tools for the modelling of groundwater...

This paper provides an understanding of the sedimentary-tectonic evolution of the Cenozoic strata of the El Habt and Ouezzane Tectonic Units (Intrarif, External Rif) in Morocco. New data provide information about the depositional architecture and enable a correlation of the evolution of the External Rif in Morocco with that of the Betic Cordillera...

La desertificación es un proceso complejo y contraintuitivo cuyo estudio demanda un enfoque multidisciplinar. Ello la convierte en un campo de investigación ideal sobre el que aplicar la Dinámica de Sistemas (DS). Se trata de una metodología de construcción de modelos dinámicos de simulación por ordenador que se concibe como herramienta de apoyo pa...

Dear Colleagues, This Special Issue aims to compile experiences that present this type of tools and proposals, including theoretical approaches and conceptualizations, numerical modelling tools and codes, and applications to case studies. The multidisciplinary and integrative character will be one of the most appreciated hallmarks of this proposal...

Dear Colleagues, This Special Issue is looking for original research exploring global driving forces and human activities determining the sustainability of coastal aquifers, including but not limited to: - Hydrological studies aimed at conceptualizing aquifer functioning and assessing the groundwater resource quantity and quality (e.g., geological,...

As in other large Andean cities, the population in the Metropolitan District of Quito (MDQ) in northern Ecuador is growing, and groundwater is becoming essential to meet the increasing urban water demand. Quito's Public Water Supply Company (EPMAPS) is promoting groundwater research for sustainable water supply, and geophysical prospecting surveys...

Dear Colleagues, We are organizing and editing a Special Issue of the Journal Applied Sciences (IF 2.217, ISSN 2076-3417; https://www.mdpi.com/journal/applsci) entitled "Integrated Geophysical Methods for Shallow Aquifers Characterization and Modelling” and would like to invite you to submit a manuscript. The due date for submission is 30 August 20...

In recent years, social and environmental conflicts concerning the aquaculture sector have increased. These conflicts arise from the different perception that individuals, collectives, private companies and the State have about the potential impacts of aquaculture on the environment and quality of life. The Environmental Impact Assessment (EIA) of...

This book collects recent and original contributions in the field of climate and underlying human influences on renewable groundwater resources and/or stream–aquifer interactions. The readers can find the contributions both interesting and inspiring when exploring the field of impacts of climate (past, current, and future) on natural, premeditated,...

This special issue delivers a platform in which researchers expose intersections between algorithm design, software platforms, and hardware architectures to deal with emerging challenges in the scientific field of management of water and water-dependent resources. Since the call for papers was announced in June 2019, this special issue has received...

This study evaluates the Environmental Impact Assessment (EIA) System in Chile. On the basis of the official EIA projects database (25,096 entered and 15,947 approved) over the period 1994-2018 the evaluation used 22 well-stablished international evaluation criteria to analyze strengths and weaknesses of the Chilean EIA System. The results show tha...

This paper conceptualizes and evaluates the groundwater resource in a coastal urban area hydrologically influenced by peri-urban irrigation agriculture. Adra town in southern Spain was the case study chosen to evaluate the groundwater resource contributed from the northern steep urban sector (NSUS) to the southern flat urban sector (SFUS), which be...

Rangeland productivity is strongly conditioned by the amount and temporal distribution of precipitation. Thus, the worsening of droughts with climate change could be a serious threat to their existence. This paper presents a modelling study aimed at evaluating the sensitivity of a valuable type of commercial rangelands, namely Spanish dehesas, to i...

An interdisciplinary study based on lithostratigraphic, biostratigraphic, petrographic and mineralogical analyses has been performed in order to establish the Cenozoic tectono-sedimentary evolution of the El Habt and Ouezzane Tectonic Units (External Intrarif Subzone, External Rif, Morocco). The reconstructed record allowed identification of the de...

In this study, we carried out a comparative analysis of the Chilean Environmental Impact Assessment (EIA) system using evaluation criteria compared against three countries to allow for an objective evaluation within the growing demand of society for a more creditable and trustable EIA system. A total of 18 evaluation criteria were selected from the...

This is the Editorial Article of the Special Issue "Impacts of Climate on Renewable Groundwater Resources and/or Stream-Aquifer Interactions" published in Water. Details are in: https://www.mdpi.com/journal/water/special_issues/renewable_groundwater A temporal perspective to understand how climate determines the aquifer recharge sources and the gro...

An interdisciplinary study based on lithostratigraphic, biostratigraphic, petrographic and mineralogical analyses has been performed in order to establish the Cenozoic tectono-sedimentary evolution of the El Habt and Ouezzane Tectonic Units (External Intrarif Subzone, External Rif, Morocco). The reconstructed record allowed identification of the de...

The management of droughts is a challenging issue, especially in water scarcity areas, where this problem will be exacerbated in the future. The aim of this paper is to identify potential groundwater (GW) bodies with reduced vulnerability to pumping, which can be used as buffer values to define sustainable conjunctive use management during droughts...

This paper integrates multichannel analysis of surface waves (MASW) and time-lapse electrical resistivity tomography (ERT) to define aquifer geometry and identify transient groundwater features of the Cascalheira Stream Basin Holocene alluvial aquifer (aquifer H), which contributes to the Santo André Lagoon, part of a coastal groundwater-dependent...

Desertification is a major global environmental issue exacerbated by climate change. Strategies to combat desertification include prevention which seeks to reverse the process before the system reaches the stable desertified state. One of these initiatives is to implement early warning tools. This paper presents SAT (the Spanish acronym for Early W...

The electromagnetic-wave attenuation coefficient determines the overall resolution and effective penetration depth of ground penetrating radar (GPR) surveys. Despite this relevance to the design of proper GPR surveys, the attenuation expressions are rarely used in the applied shallow groundwater research (SGR) literature. This work examines the sta...

In the framework of coastal groundwater-dependent irrigation agriculture, modelling becomes indispensable to know how this renewable resource responds to complex (usually not conceptualized nor monitored) biophysical, social, and economic interactions. Friendly user interfaces are essential to involve nonmodeling experts in exploiting and improving...

Extension parallel to fold axis represents a rarely documented tectonic process that occur in different tectonic settings such as large-scale orogenic belts, mountain ranges, and thrust and fold belts. Along the Ecuadorian Andes, extensional systems have only been reported as tectonic boundaries of local intermontane basins, pull-apart depressions...

This paper couples the Soil and Water Assessment Tool (SWAT) model and the chloride mass balance (CMB) method to improve the modeling of streamflow in high-permeability bedrock basins receiving interbasin groundwater flow (IGF). IGF refers to the naturally occurring groundwater flow beneath a topographic divide, which indicates that baseflow simula...

Oases are isolated, groundwater-dependent ecosystems placed in desert environments where a careful management of the groundwater resource is mandatory for their protection. Its remoteness has always awakened the draw of travelers. Today modern transport services have triggered the interest of conventional tourism. In spite of the flow of money to t...

A database including detailed lithology from historical 457 mechanical boreholes performed in the Llobregat River Delta (emerged and submerged sectors) in Barcelona province, northeastern Spain, is provided for public interests. All data are supplied in the Spanish version. This dataset is arranged in one *.RAR file including two folders as follows...

Adaptation to the European Higher Education Area implies a change of educational paradigm. In addition to the incorporation of academically directed activities and new tools for transmitting information, the change of approach also means new training explicitly oriented to develop the new professional competences. This paper presents the results fr...

The chloride-to-bromide molar ratio (R ≡ Cl/Br) is widely used in tracing groundwater salinity. Less experience exists on how some industrial processes such as the reverse osmosis (RO) water treatment modify the R value of desalinated water (P) and reject brine (T), and even less on how distinctive for hydrogeological applications the R changes are...

Dear Colleagues, We are organizing and editing a Special Issue of the Journal Scientific Programming (IF 1.289, ISSN 1058-9244; https://www.hindawi.com/journals/sp/) entitled "Scientific Programming Tools for Water Management" and would like to invite you to submit a manuscript. The due date for submission is 25 October 2019. May we kindly ask if y...

Dear Colleagues, We are organizing and editing a Special Issue of the Journal WATER (IF 2.524, ISSN 2073-4441; https://www.mdpi.com/journal/water) entitled "Impacts of Climate on Renewable Groundwater Resources and/or Stream-Aquifer Interactions" and would like to invite you to submit a manuscript. The due date for submission is 30 March 2020. May...

In W Portugal groundwater quality and availability are not commonly controlled factors. In this study, located in W Portugal, we performed a preliminary characterization of the shallowest carbonated aquifer materials, that we called aquifer B1, and that are part of a small aquifer system, comprising possibly perched aquifer levels and possibly conn...

In W Portugal groundwater quality and availability are not commonly controlled factors. In this study, located in W Portugal, we performed a preliminary characterization of the shallowest carbonated aquifer materials, that we called aquifer B1, and that are part of a small aquifer system, comprising possibly perched aquifer levels and possibly conn...

Climate change will modify the availability of groundwater resources in the future. Thus the evaluation of average aquifer recharge from precipitation, and its uncertainty, becomes a key subject in determining suitable countrywide water policies. The confident prediction of renewable groundwater resources requires an accurate evaluation of aquifer...

This work presents the preliminary results of the net groundwater balance (BNAS) evaluation performed at the Pita River basin headwater for the period 2011-2015. This representative area of the Andean highland ‘paramo’ covers 185 km2, is composed of Pliocene-Quaternary volcanic and volcano-sedimentary formations, and is mainly devoted to the wildli...

An interdisciplinary study of Miocene successions in the eastern External Betic Zone (South Iberian Margin) was carried out. Evidences of syn-sedimentary tectonic activity were recognized. The results enabled a better reconstruction of the stratigraphic architecture (with an improved chronostratigraphic resolution) in the framework of the Miocene f...

The damage distribution in the town of Adra (south-eastern Spain) during the 1993 and 1994 Adra earthquakes of magnitude Mw~5.0 and maximum intensity degree of VII (European Macroseismic Scale) was mainly concentrated in the southeast sector, where the low-diagenetic (soft) sediments outcrop. As new urbanizations are being planned in this sector, a...

Sedimentary and mineralogical analyses were performed in the Neogene Agost Basin (External Domain, Betic Cordillera) to reconstruct relationships between tectonics and sedimentation, and source areas evolution over time. The sedimentary analysis allowed defining two sedimentary sequences: (1) Lower Stratigraphic Unit, Serravallian p.p. and (2) Uppe...

The External Tanger Unit represents one of the most complete Cretaceous-Miocene successions in the central areas of the Internal Intrarif sub-Domain (External Rif Zones, Morocco). An interdisciplinary study has been carried out to propose a new characterization of this unit which would allow a better comprehension of the confused and complex relati...

Ground penetrating radar (GPR) is a high-resolution technique widely used in shallow groundwater prospecting. This makes GPR ideal to characterize the hydrogeological functioning of groundwater-dependent ecosystems (GDE). This paper reviews current uses of GPR in GDE research through the construction of a database comprising 91 worldwide GPR case s...

The Agost Basin is characterized by a Miocene–Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E–W to N–S....

This work illustrates the application of a simulation model to analyse how swiftly large-scale land-use changes can drive broad territories to collapse. In this sense, the economic needs of a population should not clash with the natural environment but rather be reconciled with it. Abundant literature deals with the integration of socioeconomic dri...

Mitigation strategies are crucial for desertification given that once degradation starts, other solutions are extremely expensive or unworkable. Prevention is key to handle this problem and solutions should be based on spotting and deactivating the stressors of the system. Following this topic, the Spanish Plan of Action to Combat Desertification (...

The increase in oxidative enzyme activities is related to diminished mite infestation. Some biological aspects of Raoiella indica Hirst reared on the coconut cultivars (‘Jamaican Tall’ (JT), ‘Malayan Yellow Dwarf’ (MYD), Niu Leka (NL) and a hybrid JT x MYD) were studied under laboratory conditions. Aditionally, changes in oxidative enzyme activitie...

An interdisciplinary archaeometric study concerning the Amtoudi Agadir, declared World Cultural Heritage (northern border of the Sahara Desert, southern Morocco), was performed consisting in lithostratigraphic reconstruction of the bedrock, diagnosis of constitutivematerials (stones, mortars, and wooden elements), and analyses of constructive techn...