Search

Avocado production has boomed worldwide in recent years, and Spain, including the Canary Islands, has been no exception. The number of avocado growers in the region has increased significantly as growers recognize the potential of this crop. However, several species of spider mites (Tetranychidae) pose a risk to this crop, with the genus Oligonychus being the most diverse and having the greatest economic impact. In particular, Oligonychus perseae (Tuttle, Baker and Abbatiello) has been reported as the one mainly responsible for the economic damage in major avocado-producing regions worldwide. In this paper, we aim to present an overview of the studies conducted and the measures implemented to mitigate the impact of O. perseae after its arrival in the Canary Islands. Our objective is to provide a detailed description of the current status of this pest (O. perseae), with special attention to its situation 17 years after its first appearance in avocado crops in the Canary Islands. In doing so, we aim to provide valuable insights and knowledge to understand and manage better the challenges posed by O. perseae in this region. [ABSTRACT FROM AUTHOR]

This paper analyses whether peer-to-peer (P2P) accommodation substitutes traditional accommodation, taking into account dynamic and spatial spillover effects. We also analyse the impact of the COVID-19 pandemic crisis on the demand and substitution effect. To do this, we use a spatial dynamic panel data demand model for occupancy rates related to prices of P2P accommodation units, prices of competitors (hotels and apartments) and income. Its dynamic component allows estimation of the short- and long-term effects of prices and income on P2P accommodation demand. The model was applied to the P2P accommodation demand in the Canary Islands, Spain. The results indicate that, in the pre-pandemic period, occupancy rates were positively autocorrelated, demand was own-price elastic and substitution with hotels was significant in the short-term. This substitution effect and consumer sensitivity to prices and substitution increase in the long term. However, the irruption of COVID-19 largely distorted price and income-elasticities. [ABSTRACT FROM AUTHOR]

The electricity production from Renewable Energy (RE) in isolated locations requires long-term energy storage systems. To that end, Hybrid Energy Storage Systems (HESS), through a combination of hydrogen and batteries, can benefit from the different advantages of both technologies. This paper presents a hybrid Power-to-Power (PtP) Optimal Power Dispatch (OPD) model for isolated systems with no electric grid access. Currently, the electricity supply in such cases is usually based on a mix of RE as the primary energy source sustained by a diesel genset acting as a backup generator. In this context, the model delivers the hourly energy flows between renewable production sources, energy storage devices and the electrical load, which minimises costs and Green House Gases (GHG) emissions. For validation purposes, the model was tested through its application to a case study in an isolated area in the Canary Islands, Spain. The results show that the algorithm calculates the hourly OPD successfully for a given plant sizing, considering the defined operational states of the different assets. These operational constraints showed a decrease in the PtP round-trip efficiency of 5.4% and a reduction of the hydrogen production of 9.7%. Finally, the techno-economic analysis of the results proves that the combination of hydrogen and batteries with RE production is a feasible alternative to phasing out fossil fuels for the selected case study – reducing the diesel generator usage down to 1.2% of the yearly energy supply. • Novel multi-state optimal power dispatch model for power-to-power energy systems. • Multi-year techno-economic evaluation of an off-grid case study. • Phasing out fossil fuels with renewable energy-based hybrid energy storage systems. • Hydrogen technology contributes to a lower levelized cost of energy. • High initial investment cost was a significant entry barrier to deploying hydrogen. [ABSTRACT FROM AUTHOR]

So far in the literature, the two-parameter Weibull distribution and its other extensions are frequently implemented to analyze the wind speed energy data sets. However, based on our study of the literature, there is no published work about analyzing the wind speed energy data sets using new probability distributions that are developed via trigonometric functions. In this paper, I attempt to cover this amazing and interesting research gap. Therefore, I incorporate a trigonometric function, especially, the sine function to introduce a new statistical distributional method. The proposed method is called a new modified sine- G family of distributions. Some distributional properties of the new modified sine- G method are obtained. Using the new modified sine- G method, a new extension of the Weibull distribution called a new modified sine-Weibull distribution is studied. The new modified sine-Weibull distribution is applied to analyze four wind speed energy data sets. All three data sets are taken from the weather station at Sotavento Galicia in the Canary Islands, Spain, located at 43.3544 North and 7.8812 West. [ABSTRACT FROM AUTHOR]

Occupational stress, as a negative facet, is a pervasive problem with significant implications for organizations, employees, welfare systems and health. The implementation of measurement tools that can capture the different organizational dimensions that determine stress in workers is part of the stress management and troubleshooting strategy that every company must manage daily. The aim of the present study was to adapt and validate the 25-item version of the ILO-WHO stress scale by Ivancevich and Matteson in the context of the Canary Islands of Spain. The tool assesses specific organizational dimensions of work-related stress determinants: organizational climate and structure, leader influence, cohesion, territory, technology and group support. An exploratory factor analysis (EFA) on a sample of 1510 Canary Islands workers was carried out. The results indicate that the job stress scale revealed adequate psychometric properties, construct validity and internal consistency (Cronbach's alpha = 0.972), and it can be profitably used to measure stress. At the end of the paper, theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

The location, size, and structure of the farmlands and hydraulic systems built by the Indigenous inhabitants of Gran Canaria, Canary Islands, Spain, remain unknown. This hampers our ability to understand how they organized agricultural production and how European settlers transformed local landscapes to build commercial plantations in the late fifteenth century. This paper combines an analysis of archival sources with the study of agricultural landscapes and practices to identify and describe the fields that were employed by the first colonists of Agüimes and Temisas, and to derive information about the location, design, and management of the pre-Hispanic farmlands. [ABSTRACT FROM AUTHOR]

This paper analyzes different forms of violence identified among the ancient Canarians, a population that settled an oceanic island and remained there, without regular external contacts, for more than a millennium. Specifically, we focus on a funerary deposit composed of 14 individuals with high rates of violence, in some cases of a lethal nature. The study uses forensic anthropology techniques to characterize the individuals' injuries. It also explores the chrono-cultural framework in which they were inserted for an historical explanation. The high frequency of individuals with evidence of violence, the features of traumatic injuries, and the radiocarbon data suggest an event of extreme physical violence. This episode appears to be linked to socioeconomic changes, including population growth, marked social differences, rivalry between groups, and competition for control of the resources in a small and diverse territory. The different patterns of violence identified among the skeletal remains in Gran Canaria serve to explore the nature of human relations over a prolonged period in an insular context. [ABSTRACT FROM AUTHOR]

Copyright of Flora Montibérica is the property of Flora Montiberica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study is to assess the importance of geotourism before, during and after the eruption of the Tajogaite Volcano (September to December 2021) on La Palma, Spain. The methodology applied consisted of identifying the geotourism products on the island before the eruption, the importance of the volcano for geotourism – by means of a survey – and the geotourism products developed after the eruption. The findings show that, before the eruption, La Palma's tourism products (hiking, archaeology, stargazing and volcano tourism) were closely related to its volcanic heritage. During the eruption, Tajogaite became a tourist attraction for the island, drawing thousands of visitors and scientists. Lastly, now that the eruption has ended, geotourism is playing a key role in the various island recovery plans through the evaluation of sites of geotourism interest and the design of geotrails in natural and urban areas. [ABSTRACT FROM AUTHOR]

This study addresses the in situ mobility of fluoride and aluminum in two different ashfall deposits accumulated during the 2021 eruption of the Tajogaite volcano (La Palma, Canary Islands, Spain), which were exposed to contrasting conditions of ambient humidity and precipitation. We selected one site to the east of the volcanic emission center, located near the top of Cumbre Vieja Ridge and exposed to continuous humidity and rain, and another site to the west of the volcano situated in a lowland and characterized by much drier conditions. The mobility of fluoride and aluminum is markedly different at both sites, with the first sequence suggesting a downwards migration of Al and F, and the second sequence showing no sign of mobility. The migration of aluminum and fluorine results from the dissolution of different fluoride salts (mostly AlF3 and CaF2, as suggested by scanning electron microscopy) followed by vertical transport as ionic complexes (AlF3, AlF2+, AlF4−) during the percolation of rainwater through the ashfall deposits. Geochemical calculations suggest that the mobility of fluorine at neutral to alkaline conditions (pH 7.0–9.0) is likely limited by the solubility of fluorite (CaF2), whereas at slightly acidic conditions (pH < 6.5), the aqueous concentration of aluminum seems to be controlled by the solubility of gibbsite (Al(OH)3). This study demonstrates that aluminum and fluoride can be transported from volcanic ash to the underlying soil or groundwater, which is an environmental concern that should be followed in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Trypanosomosis is a widespread issue in animals, resulting in significant economic losses, particularly in Africa. In Spain, only one pathogenic species, Trypanosoma evansi, has been identified. Since its first detection in a dromedary camel in the Canary Islands in 1997, cases of the disease, known as Surra, have continued to be diagnosed, leading to various studies and control efforts. Due to the lack of a comprehensive database consolidating the most relevant data on T. evansi in Spain, the development of a national atlas was deemed necessary, with a focus on the Canary Islands. To develop the atlas, a repository was created that compiled data and documents from 1997 to 2022. Information from different sources, including georeferenced locations and blood test results, was extracted and integrated into a comprehensive database. The analysis of 31 sources provided 99 georeferenced locations and 12,433 animal samples. Out of these samples, 601 were found to be positive for T. evansi, mostly from dromedaries. The Card Agglutination Test for T. evansi (CATT/T. evansi) was the most commonly used diagnostic method, showing a higher prevalence for all tested animal species. The positive cases were primarily concentrated in the Canary Islands, specifically in the eastern islands, with a few isolated cases in the province of Alicante in the Iberian Peninsula. This atlas serves as a comprehensive overview of the history and prevalence of Surra in Spain and provides a valuable tool for future control initiatives and research. However, further studies are still needed to investigate potential hosts other than camelids and their associated transmission vectors. Trypanosomosis is a global animal issue, causing significant economic losses, particularly in Africa. In Spain, only one pathogenic species, Trypanosoma evansi, has been identified so far. It was first detected in a dromedary camel in the Canary Islands in 1997. Since then, numerous cases of the disease, known as Surra, have been diagnosed, prompting various studies and efforts in control and surveillance. Given the lack of a comprehensive database that consolidates the most relevant data in this area, the development of a national atlas, with a focus on the Canary Islands, to incorporate all available information on T. evansi in Spain became a necessity. For the development of the atlas, a repository was constructed, encompassing a range of datasets and documents spanning from 1997 to 2022. Information from each source, and in particular georeferenced locations and results of blood tests on animals, were extracted and integrated into a comprehensive database. A total of 31 sources were analysed, providing a total of 99 georeferenced locations and 12,433 animal samples. Out of these samples, 601 (mostly from dromedaries) were found to be positive for T. evansi. The Card Agglutination Test for T. evansi (CATT/T. evansi), a serological test, was the most commonly used diagnostic method, and it showed a higher prevalence for all tested animal species. Positive cases were mainly concentrated in the Canary Islands, specifically in the eastern islands, with isolated cases found in the province of Alicante (Iberian Peninsula). This atlas provides an overview of the history and occurrence of Surra in Spain, and it represents a valuable tool for future control initiatives and for research. Still, the need for more studies remains, especially for further testing of potential hosts other than camelids and for the examination of their potential transmission vectors. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) have been identified as significant point sources of microlitter particles (MPs) released into the environment. Simultaneously, they play a crucial role in effectively removing a substantial amount of MPs originated from domestic and industrial activities. This study evaluates the presence and chemical composition of MPs within the range of 5 mm to 25 µm in effluents from three WWTPs in the Canary Islands, each undergoing distinct treatment processes: pretreatment (PRET), activated sludge (AS), and membrane bioreactor (MBR) over an eight-month period. The concentrations of MPs exhibited substantial variations in the three effluent samples: 7461.50 ± 3843.87 MP/L in PRET, 32.71 ± 19.55 MP/L in AS, and 9.53 ± 5.21 MP/L in MBR. The predominant forms of MPs were fragments (58–66%) and fibers (27–33%), with the most prevalent size class being within the range of 150–25 µm. The mass concentrations of plastics, analyzed through pyrolysis gas chromatography–mass spectrometry (Pyr-GC/MS), were determined as 123.33 µg/L for PRET, 17 µg/L for AS, and 10 µg/L for MBR. This study revealed a diverse polymer profile, with polyvinyl chloride (PVC) and polyolefins (PE and PP) predominantly present. This work enhances our understanding of MP dynamics and provides a valuable reference for future assessments, aiding in the selection of effective removal technologies. [ABSTRACT FROM AUTHOR]

The aim of this research work is to study the effect of salt mist ageing on the physico-mechanical properties of two ignimbrites from the Canary Islands (Spain). Due to their insular nature and extensive coastlines, these regions are highly susceptible to atmospheric salt aerosols, which is a significant weathering agent for building materials. The ignimbrites analysed are marketed under the names "Azul Lomo Tomás de León" and "Marrón de Abades" and are widely used as building stones. Petrographic, mineralogical and chemical properties were obtained via polarisation microscopy, X-ray diffraction and X-ray fluorescence. The samples were subjected to 60 cycles of a salt mist environment, following relevant European standards. Scanning electron microscopy images of the specimens were analysed along with physical properties, including apparent density, open porosity, water absorption, colourimetry and ultrasound propagation velocity, initially and after every 20 cycles, allowing us to assess their evolution during the ageing test. Mechanical properties were evaluated using uniaxial compressive strength and flexural strength under concentrated load tests on two groups of specimens: one unaged and the other subjected to 60 ageing cycles. With the exception of apparent density, the other properties show a decrease between 5% and 30%. However, open porosity increases and is one of the properties most affected by the ageing test. [ABSTRACT FROM AUTHOR]

The aim of this paper is to describe and compare seasonal effects in daily air passenger arrivals. Multiple seasonal cycles of different lengths are usually observed in daily time series. To model weekly cycles over a short and fixed seasonal period, conventional formulations can be applied. However, the length of yearly and, above all, monthly seasonal cycles is not fixed. Yet, whatever the lengths of the seasonal periods, seasonal cycles can be modelled by using evolving spline functions in such a way that a seasonal effect at a proportion of the seasonal period is defined as a non-fixed parametric formulation of this proportion. Thus, restricted evolving spline models are useful to model this type of seasonal variation. The areas under the splines can measure changes in the magnitude of seasonal variations over time and can be used to compare the relevance of seasonal variations for different seasonal periods or different time series. This proposal is illustrated by applying it to daily series of air passengers arriving in the Canary Islands and at the rest of Spain's airports. • Complex seasonal patterns are described for daily series of air passenger arrivals. • Monthly seasonal cycles are modelled with non-fixed lengths of seasonal periods. • Restricted evolving spline models are applied to capture changing seasonal cycles. • The relative magnitude of weekly, monthly and yearly seasonal cycles is assessed. • Dissimilarity and complementarity between different seasonal cycles is measured. [ABSTRACT FROM AUTHOR]

Subsidizing residents on airlines is a common policy in a number of countries. However, the question arises as to how changes in this policy affect the travel behavior of residents in specific regions? To address this, we analyze the effect of an "exogenous shock" (i.e., an increase in the resident subsidy) on two Spanish archipelagos when they travel away from the islands. Our Difference-in-Difference and matching estimations find that the causal impact of the policy change is different for resident passengers across the two regions affected. Although the length of stay was reduced for resident passengers in both archipelagos by 10%–15% after the shock, their expenditure at destination per day increased by 13% on the Balearic Islands, while showing no significant change on the Canary Islands. J.E.L. Codes: L83; H25; L93 [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the geomagnetically induced current (GIC) hazard in the power networks of the Canary and Balearic archipelagos. This is done in order to strictly complete the detailed assessment at national level of the power transmission system of mainland Spain, including the 400 and 220 kV levels. We have constructed models for the grids in each of the individual systems and used resistivity models of the lithosphere for each group of islands, from which we have calculated the surface impedances. The respective models of electrical admittances of the grids have been combined with the geoelectric field derived from the convolution of the recorded (or expected in an extreme scenario) geomagnetic storms and the impedances calculated from the geoelectrical models to derive the expected GICs in the power lines, substations, and transformers. The low geomagnetic latitude of the Canary Islands combined with the small size of their power networks, makes them one of the least likely electrified locations to record significant GICs, with less than 3 A for the 100‐year return period. Even the 13 A that could be reached for the upper limit of the 95% confidence interval at the 500‐year return period does not seem likely to have a significant impact. The Balearic Islands, being at higher latitude and with a system length of approximately 300 km, including alternating current power lines connecting the Islands, shows GIC signals of moderate amplitude with up to 40 A for the 100‐year return period. Plain Language Summary: In the same way that phenomena derived from meteorological processes can have devastating effects, the Sun emits massive amounts of particles and energy into space that affect Earth technological systems. The related science is analogically called space weather. When the Sun is active, it sends out more charged particles that can affect the regions around the Earth where those particles interact with the planet's magnetic field. This leads to a significant increase of electric currents in these media giving rise to geomagnetic storms. This generated electrical fields act like a voltage source and cause electrical currents to flow through the power networks, that can damage the transformers where the circuit is grounded. Many countries, such as Spain, have undertaken studies to assess the vulnerability of their power grids to the danger posed by this phenomenon, but one question that remained open was whether the grids that transmit power across their islands deserve attention. Our results show that the vulnerability of the Canary Islands is very low, while that of the Balearic Islands is not negligible. Key Points: We quantify the historical geomagnetically induced currents (GICs) and the worst‐case scenarios in the power grids of the Spanish IslandsCanary Islands is one of the least likely electrified locations in the world to record significant GICsThe Balearic Islands, with their higher latitude and long power lines connecting the islands between them, are more vulnerable to GIC [ABSTRACT FROM AUTHOR]

The explosive activity of the 2021 Tajogaite eruption eludes pigeonholing into well‐defined eruption styles, with a variety of pyroclast ejection modes occurring both alternately and simultaneously at multiple vents. Visually, we defined four endmembers of explosive activity, referred to as fountaining, spattering, ash‐poor jets and ash‐rich jets. To capture the physical parameters of these activities, we deployed a camera array including one high‐speed camera and three high‐definition cameras in two field campaigns. Transitions between and fluctuations within activity occurred at the time scale of minutes to hours, likely driven by the same shallow conduit and vent processes controlling Strombolian activity at other volcanoes, but at higher gas and magma fluxes. From a physical standpoint, mean pyroclast rise velocity ranged 5–50 m/s, maximum ejection velocity 10–220 m/s, and sub‐second mass flux of lapilli to bomb‐sized pyroclasts at the vent 0.2–200 × 103 kg/s. The largest mass flux occurred during fountaining, which contributed by far more than other activities to cone building. All explosive activity exhibited well‐defined pyroclast ejection pulses, and we found a positive correlation between the occurrence rate of ejection pulses and maximum pyroclast ejection velocity. Despite orders of magnitude variations, physical parameters shift gradually with no boundary from one activity endmember to another. As such, attributing this explosive activity specifically to any currently defined style variations is arbitrary and potentially misleading. The highly variable explosive activity of the Tajogaite eruption recalls previous definitions of violent Strombolian eruptions, an eruption style whose pyroclast ejection dynamics, however, were so far largely undefined. Plain Language Summary: The 2021 Tajogaite volcanic eruption offered a rare opportunity to study in detail the physical properties and the controlling factors of explosive activity driven by basaltic magmas. The activity lasted almost uninterrupted for almost 3 months and had visually different manifestations occurring simultaneously and alternating at different volcanic vents. To study the explosive activity, we used one high‐speed camera, taking short, slow motion videos, and three commercial grade high‐definition camcorders recording for many hours. We found that the activity changed in features and intensity at the time scale of minutes to hours, largely controlled by changes in the size and debris cover of the vent, magma viscosity, and magma flux and gas content. The ejection velocity of large volcanic particles ranged 5–220 m/s, with mean values around 10–50 m/s. The mass flux of particles erupted reached peaks of 200 metric tons per second. Particle ejection was never steady but always proceeded in pulses, which were more frequent if the ejection velocity was higher. Our measurements show that the current classification schemes for explosive eruptions of basaltic magmas do not adequately describe the activity of the Tajogaite eruption, which represents a type of eruption that was not yet measured in detail. Key Points: High‐definition and high‐speed imaging record the velocity, size, and mass flux of pyroclastsActivity shifted in location, nature and vigor at the time scale of hours and progressed in ejection pulses at the time scale of secondsPhysical parameters of explosive activity vary gradually between apparently different activity styles, without any clear boundary [ABSTRACT FROM AUTHOR]

The recent eruption of the Cumbre Vieja Volcanic Ridge in La Palma started on September 19, 2021, after a series of seismic swarms and lasted 85 days. Seismic swarms showed a large variability but could be grouped in two categories: long-term swarms located at subcrustal depth, showing b-values close to 2.2 and low rates (from 4.1 to 56 events/hour) and short-term swarms located at very shallow depths, showing moderate b-values [0.9, 1.6] and high rates (from 58 to 460 events/hour). Magma ascent velocity within the 0–10 km depth range varied between 0.03 and 0.21 km/h. Spatial and temporal characterization of the b-values for the entire magmatic process during the selected study period also indicated three distinct dynamics during a preparation phase starting from at least October 2017–August 2021, the eruptive phase from September 2021–December 2021 and a post-eruption process from the end of the eruption in December 2021–May 2022. These stages with clearly different values reflect two scenarios: one corresponding to the time before the eruption with magma ascending from a 39-km depth to the surface, and a second stage corresponding to the eruption itself which includes two seismicity concentrations within the 30–40 km depth interval and a shallow concentration from 0–20 km, corresponding to the crustal reservoir and movement towards the surface. [ABSTRACT FROM AUTHOR]

Redox chemistry controls the behavior of mercury during long‐range atmospheric transport. Despite major progress in understanding the oxidation process in the atmosphere, the mechanism of mercury reduction, especially the aqueous‐phase and multi‐phase reactions in cloudwater, remains poorly known. Here we report experimentally determined rates of in‐cloud mercury photoreduction using cloudwater samples collected from a forested area in the Canary Islands, Spain. Mercury concentrations in cloudwater varied greatly from 0.04 to 19.9 nM (7.89 ± 6.11 nM) for total mercury and 0.02 to 4.98 nM (1.16 ± 1.49 nM) for the dissolved fraction, with particulate mercury being the dominant fraction in most of the samples. The mercury concentrations were elevated in comparison with those previously reported for atmospheric waters, reflecting the impact of a large‐scale forest wildfire that occurred shortly before the sampling campaign on a neighboring island. Mercury photoreduction was determined by two independent methods: under natural solar radiation at a nearby mountain site located in the free troposphere and under UV radiation in the laboratory. In addition to aqueous‐phase photoreduction, multi‐phase photoreduction involving particulate mercury also occurred in cloudwater, with the latter becoming dominant once dissolved mercury had been depleted. Overall, the pseudo‐first‐order rate constants for in‐cloud mercury photoreduction varied from 0.07 to 0.21 hr−1, which are one order of magnitude lower than the values presumed in global mercury transport models. Our results suggest that in‐cloud reactions alone are insufficient to account for mercury reduction in the atmosphere and that other pathways, such as gas‐phase reactions, must exist and need to be properly incorporated into future models. Plain Language Summary: In the atmosphere, mercury is a contaminant that resides in gases and aerosols, and it is transported globally via atmospheric circulation. During the transport, the fate of mercury is largely controlled by photochemical oxidation and reduction. However, the photoreduction mechanism, especially that in cloudwater, remains poorly studied. In this study, we measured mercury photoreduction rates in cloudwater collected from a forested area in the Canary Islands, Spain. We show that the experimentally determined in‐cloud mercury photoreduction rates are much lower than the values required by current mercury transport models. We further show that in addition to dissolved mercury, particulate mercury in cloudwater also undergoes photoreduction. Accordingly, models must update atmospheric mercury photoreduction schemes to account for other reduction pathways. Key Points: Highly elevated mercury concentrations are found in cloudwater impacted by forest wildfiresExperimentally determined in‐cloud mercury photoreduction rate constants are one order of magnitude slower than models assumedParticulate mercury in cloudwater can also be photoreduced to elemental mercury via multi‐phase reactions [ABSTRACT FROM AUTHOR]

The most recent years of research have shifted the perception of desalination brine from being waste to a high-value resource, in consonance with a circular economy perspective. The Canary Islands, containing the largest number of desalination plants per square kilometre in the world, are a perfect location to study its characteristics and evaluate its potential. A total of 10 heterogeneous seawater reverse osmosis plants were selected to determine the brine's physicochemical characterisation, comprising 37 parameters, and its correlation to the technical and operational aspects of the desalination plants. The results show a stable narrow range of the percentage of major ions concentration in relation to the total dissolved solids (55% Cl−, 29.5% Na+, 8% SO42−, 4% Mg2+, 1.5% Ca2+, 1.2% K+, 0.5% HCO3−, and 0.2% Br−) irrespective of specific differences between plants. The results obtained in this study are highly beneficial to industrial suppliers and future users of desalination brine valorisation (DBV) technologies, allowing an estimation of the chemical composition of a brine through knowledge only of its conductivity. Such information is crucial before investing in and optimizing DBV technologies. Nonetheless, from an environmental, economic, operational, energy-based, and R&D point of view, several improvements are required to promote their large-scale feasibility and viability. [ABSTRACT FROM AUTHOR]

The island of Lanzarote in the Canary Islands was first settled by people from northern Africa in the first millennium BC and then colonized by Spain in the late fifteenth century. This colonial legacy reflects an intensive land use driven by a European commodities market that experienced a series of boom-and-bust cycles. Although arid and seemingly resource limited, colonial farmers in the sixteenth to nineteenth centuries copied water capture techniques from the Indigenous population, were strategic in terms of field placement, and engaged in a range of niche construction techniques. An analysis of 420 soil samples for their chemical properties (e.g., pH, electrical conductivity, nutrients) has revealed that sixteenth to nineteenth agricultural infrastructure in the form of open fields, terraces, water capture basins, and mulched fields was constructed on the landscape avoiding areas of high soil salinity and placement was tailored to variations in terrain slope, elevation, and rainfall. These improvements fundamentally changed ecosystem relations resulting in increased agricultural productivity. A series of eolian and volcanic events in the eighteenth century resulted in environmental changes requiring counteractive responses and new processes of niche reconfiguration. Large tracts of land were initially removed from production, but processes of niche construction created new opportunities. These included constructing mulched pits for cultivating sweet potato and tephra mulching for enhanced moisture conservation and accelerated growth of cochineal insect (Dactylopius coccus) production on cactus host plants. Cochineal production lasted for a period of sixty years (ca. AD 1825–1885) before a collapse of the market caused by the invention of chemical substitutes. [ABSTRACT FROM AUTHOR]

Several countries around the world have implemented policies to subsidize passengers who live on islands and travel domestically by air transport. This paper analyzes the effect of an exogenous change in the percentage of air transport resident subsidies in Spain on non-residents tourists' expenditure per day and overnight stays in corresponding regions. Drawing on monthly data from the period 2015–2019, a difference-in-difference estimator is applied, in addition to several robustness checks and placebo tests. We found a negative causal relationship between raising the subsidy percentage and non-residents tourists' expenditure per day on affected routes (routes between the mainland and islands). In fact, estimations show a reduction of between 9.6 and 12.2 per cent of non-residents tourists' expenditure per day on the Canary Islands. • Does a rise in the percentage of resident subsidies affect touristic expenditure and overnight stays? • A monthly sample of spanyards who travel within Spain (2015–2019) is used. • We use dif-in-dif estimator with OLS and QR, robustness checks and placebos tests. • Non-residents tourists' expenditure per day in Canary Islands drops due to subsidy change. [ABSTRACT FROM AUTHOR]

The geological survey has been carried out in El Hierro with the aim to produce a new Geological Map at 1:12,500 scale for the Southern Rift. Almost 70 km² have been mapped providing a detailed stratigraphic and volcano-tectonic reconstruction of its evolution. Our work focused on the last Rift Volcanism phase, where hundreds of cinder cones, associated with thin lava flows, cover most of the island’s surface. Lava flows fields (40), monogenetic volcanic edifices (>90), and volcano–tectonic structures (69), such as dykes, eruptive fissures, and faults have been surveyed and stored in the Geological Map. The map poses fundamental constraints on the Southern Rift geological evolution, mainly concerning its recent activity and allowing the definition of 4 main stages during the last 40 ka. Moreover, this 1:12,500 scale detailed map represents a primary tool for the volcanic hazard assessment of the Island, volcanic monitoring, urban planning, and further stratigraphic data-based investigations. [ABSTRACT FROM AUTHOR]

Purpose: The main research questions addressed by this study focus on Subjective Well-Being (SWB) and to what extent the individual's SWB relates to the individual's need for personal growth. Specific interest is devoted to the effects of intentions (to have personal goals) and behavior (to achieve personal goals). Design/methodology/approach: Can SWB and happiness research help to explain the tremendous growth in demanding amateur sport event participation? Most research on SWB and events has, so far been undertaken on cultural events leaving a gap related to sport events, especially obstacle running events. Bestial is an obstacle race event held in Arucas on Canary Islands, Spain. Apart from competitiveness, the race also contains elements of altruism as many competitors do help each other at various obstacles along the route, in groups (mainly) teams. A sample of 700 participants answered questions about behavior, attitudes and SWB. Findings: The results show significant relations between SWB and both intentions and behavior but also that intentions and behavior are not correlated. Research limitations/implications: The "Bestial" is different from an average running event in some respects. It is a rather local event for Gran Canaria without international participation. For some participants it is more challenging and enduring but for others it is a team sport where one helps other team members to complete the race. In this study, these two types of participation have not been separated. The test of whether the SWB of participants is higher than the SWB of the average citizen is not satisfactory. Data for the average of SWB in Spain had to depend on a study from another year and where standard deviation was not available. Practical implications: The results of this work are useful for event managers to improve their design and develop the most appropriate marketing messages. Social implications: The study aims for an explanation to why demanding physical activities, such as obstacle races, are so popular. In this study of obstacle race participation, hedonia is regarded as less relevant and focus is on eudaimonia and an assumption that participants in an obstacle race have a high SWB since they can feel that they make progress towards goals. One intended contribution of this study is to distinguish between "to have a goal" and "to progress towards a goal". Thus, the model proposed is based on hypotheses that SWB is influenced by both. Two types of goals are studied: first a mainly individualistic goal of becoming physically fit and second a more altruistic goal of "becoming a better person". Originality/value: In the conclusions, the importance for a happy life of simply having goals for personal growth and the value of anticipation for happiness is discussed. [ABSTRACT FROM AUTHOR]

This study provides evidence about the degree of socioeconomic segregation in Spain's primary schools. In particular, the analysis is based on data from Canary Islands, a Spanish region with low level of academic performance and high level of students enrolled in fully public schools. The approach used to study school segregation deepens on the contribution of the type of school funding to the overall school segregation, which is addressed using the Hutchens Index. Results suggest that differences between fully state-funded schools and private schools account for 20–30% of the total level of segregation. [ABSTRACT FROM AUTHOR]

Research Findings: Universal screening is the first stage in identifying students at risk for reading difficulties within a Response to Intervention model. However, there is a lack of validated screening tools for assessing reading abilities in first-grade students from Spain. This pilot study examines the technical adequacy, classification accuracy, and best predictors within a set of curriculum-based measures (CBMs) in Spanish. A sample of 178 first graders from urban and peripheral areas of Santa Cruz de Tenerife (the Canary Islands, Spain) was assessed in the fall, winter, and spring. Receiver operating characteristic curves and logistic regression models were conducted to evaluate the predictive validity of each CBM and their composite score. In addition, students' learning growth on each CBM was analyzed using hierarchical linear models. Although results suggested that most of the CBMs had adequate reliability and validity throughout first grade and were able to detect students' growth, some measures showed low reliability and validity coefficients. Practice or Policy: Some of the studied CBMs could potentially be used as universal screening to early detect reading difficulties in this population. A two-stage gated screening procedure is proposed for future research and practical implementation using oral reading fluency in the first step. [ABSTRACT FROM AUTHOR]

Remote spectral imaging of coastal areas can provide valuable information for their sustainable management and conservation of their biodiversity. Unfortunately, such areas are very sensitive to changes due to human activity, natural phenomenon, introduction of non-native species, and climate change. Thus, the main objective of this research is the implementation of a robust image processing methodology to produce accurate bathymetry maps in shallow coastal waters using high-resolution multispectral WorldView-2/3 satellite imagery for the monitoring at the maximum spatial and spectral resolutions. Two different island ecosystems have been selected for the assessment, since they stand out for their richness in endemic species and they are more vulnerable to climate change: Cabrera National Park and Maspalomas Natural Protected area, located in the Balearic and Canary Islands, Spain, respectively. In addition, a third example to show the applicability of the mapping methodology to monitor the construction of a new port in Granadilla (Canary Islands) is presented. Contributions of this work focus on improving the preprocessing methodology and, mainly, on the proposal and assessment of new satellite-derived regression and machine learning bathymetric models, which have been validated and compared with respect to measured reference bathymetry. After a thorough analysis of nine techniques, using visual and quantitative statistical parameters, ensemble learning approaches have demonstrated excellent performance, even in challenging scenarios up to 35-m depth, with mean RMSE values around 2 m. [ABSTRACT FROM AUTHOR]

The concept of geodiversity is becoming more widely used every year, beyond its contribution to the development of geotourism. It is estimated that geodiversity is as important as biodiversity in the functioning of Earth's natural ecosystems. Therefore, an important problem is to recognize the possibilities on integrating geodiversity in geographic education, both formal and informal. The main aim of the study is to identify the subject of educating godiversity, included in the core curricula in Spain and Canary Islands and to identify the forms, didactic tools and methods of geodiversity education existed in selected national, natural parks and geoparks of Canary Islands. The study has shown that the application of geodiversity in educational practice is still unsettled. [ABSTRACT FROM AUTHOR]

The organic wine market is rapidly growing worldwide, both in terms of production and consumption. However, the scientific literature is not conclusive regarding differences in the elemental composition of wines according to their production method, including both major and trace elements. Minerals can be present in wine as a result of both anthropogenic and environmental factors. To date, this has not been evaluated in volcanic contexts, neither has the emergent issue of rare earths and other minority elements as potential sources of food contamination. This study using inductively coupled plasma mass spectrometry (ICP-MS) analyses organic and conventional wines produced in the Canary Islands (Spain), an archipelago of volcanic origin, to compare their content of 49 elements, including rare earths and minority elements. Our results showed that organic wines presented lower potential toxic element content on average than their conventional counterparts, but differences were not significant. Geographical origin of the wine samples (island) was the only significant variable differentiating wine samples by their composition profiles. By comparing our data with the literature, no agreement was found in terms of differences between organic and conventionally-produced wines. This confirms that other factors prevail over elemental composition when considering differences between wine production methods. Regarding the toxicological profile of the wines, five samples (three organic and two conventional) exceeded the maximum limits established by international legislation. This highlights the need for stricter analytical monitoring in the Canary Islands, with a particular focus on Cu and Ni concentration, and potentially in other volcanic areas. [ABSTRACT FROM AUTHOR]

Background: The Culicoides obsoletus species complex (henceforth 'Obsoletus complex') is implicated in the transmission of several arboviruses that can cause severe disease in livestock, such as bluetongue, African horse sickness, epizootic hemorrhagic disease and Schmallenberg disease. Thus, this study aimed to increase our knowledge of the composition and genetic diversity of the Obsoletus complex by partial sequencing of the cytochrome c oxidase I (cox1) gene in poorly studied areas of Spain. Methods: A study of C. obsoletus populations was carried out using a single-tube multiplex polymerase chain reaction (PCR) assay that was designed to differentiate the Obsoletus complex sibling species Culicoides obsoletus and Culicoides scoticus, based on the partial amplification of the cox1 gene, as well as cox1 georeferenced sequences from Spain available at GenBank. We sampled 117 insects of the Obsoletus complex from six locations and used a total of 238 sequences of C. obsoletus (ss) individuals (sampled here, and from GenBank) from 14 sites in mainland Spain, the Balearic Islands and the Canary Islands for genetic diversity and phylogenetic analyses. Results: We identified 90 C. obsoletus (ss), 19 Culicoides scoticus and five Culicoides montanus midges from the six collection sites sampled, and found that the genetic diversity of C. obsoletus (ss) were higher in mainland Spain than in the Canary Islands. The multiplex PCR had limitations in terms of specificity, and no cryptic species within the Obsoletus complex were identified. Conclusions: Within the Obsoletus complex, C. obsoletus (ss) was the predominant species in the analyzed sites of mainland Spain. Information about the species composition of the Obsoletus complex could be of relevance for future epidemiological studies when specific aspects of the vector competence and capacity of each species have been identified. Our results indicate that the intraspecific divergence is higher in C. obsoletus (ss) northern populations, and demonstrate the isolation of C. obsoletus (ss) populations of the Canary Islands. [ABSTRACT FROM AUTHOR]

The article analyzes the public's response to a hypothetical room tax applied to overnight stays in the Canary Islands. Topics include the use of room taxes in Spain, main findings from the opinion survey about a room tax in Gran Canaria, Spain, and results of stated choice survey and accompanying discrete choice model estimation.

In this work, a mathematical computer simulation model is used to predict the possible energy generated from different Waves Energy Converters (WECs) in the Canary Islands. The Monte Carlo Method is the computer simulation model proposed to predict the generated energy. The Waves Energy Converter systems analyzed in the study were, the Aqua Buoy, Wave Dragon and Pelamis converters. The models were implemented and validated, with the dataset of Gran Canaria deep water buoy. This buoy belongs to a network of buoys belonging to Spain's State Ports and they cover a dataset period of 22 years. The research has concluded that it is possible to affirm that the achieved model is a strong tool to compute the possible energy of any WECs, when the power matrix is known. The model based on the Monte Carlo simulation can be used in isolated islands of the Atlantic Ocean and can be extrapolated to other regions with the same characteristics. [ABSTRACT FROM AUTHOR]