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Water scarcity is a global problem that particularly affects islands located in arid regions or regions with limited water resources. This issue has prompted the development of non-conventional water sources such as fossil fuel-powered desalination systems. Concern about the high energy and environmental costs associated with this type of facility has created the ideal framework for the proliferation of desalination projects powered by renewable energies, especially wind energy due to the multiple advantages it offers. This article provides a bibliometric analysis to identify the advances made in wind-powered desalination on islands. While many studies explore wind-powered desalination, none compile references specific to islands. This paper analyses islands' desalination needs and showcases wind-powered systems, exploring their types and uses. Firstly, the most relevant international scientific journals are identified to allow the subsequent selection and quantitative and qualitative analysis of articles directly dealing with wind-powered desalination systems. A total of 2344 articles obtained from the Scopus database were analyzed, of which 144 including 181 case studies were selected. Among the results of this study, an increasing year-on-year trend is observed in the number of published studies tackling wind-powered desalination. Finally, this paper presents a series of maps showing the most relevant facilities, projects, and data in this field, and provides an overview of the lessons learned in the decarbonization of desalination. [ABSTRACT FROM AUTHOR]

With the increasing popularity of IoT (Internet-of-Things) devices, their security becomes an increasingly important issue. Buffer overflow vulnerabilities have been known for decades, but are still relevant, especially for embedded devices where certain security measures cannot be implemented due to hardware restrictions or simply due to their impact on performance. Therefore, many buffer overflow detection mechanisms check for overflows only before critical data are used. All data that an attacker could use for his own purposes can be considered critical. It is, therefore, essential that all critical data are checked between writing a buffer and its usage. This paper presents a vulnerability of the ESP32 microcontroller, used in millions of IoT devices, that is based on a pointer that is not protected by classic buffer overflow detection mechanisms such as Stack Canaries or Shadow Stacks. This paper discusses the implications of vulnerability and presents mitigation techniques, including a patch, that fixes the vulnerability. The overhead of the patch is evaluated using simulation as well as an ESP32-WROVER-E development board. We showed that, in the simulation with 32 general-purpose registers, the overhead for the CoreMark benchmark ranges between 0.1% and 0.4%. On the ESP32, which uses an Xtensa LX6 core with 64 general-purpose registers, the overhead went down to below 0.01%. A worst-case scenario, modeled by a synthetic benchmark, showed overheads up to 9.68%. [ABSTRACT FROM AUTHOR]

Simple Summary: The main assumption of the so-called theory of island biogeography is that larger islands are home to more species than smaller ones. However, species richness on an island is affected not only by its size but also by other features, such as the island's distance from the mainland or its geological age. The two Canary Islands Tenerife and La Gomera are a good model for testing the relationship between species richness and island area, as they differ considerably in size (the former has an area 5.5 times that of the latter) but are similar in location and age. They lie close to each other (less than 30 km apart) in the central-western part of the archipelago, about 300 km from the African coast. Both were formed as a result of volcanic activity some 11.5–12 million years ago. We compared the species composition and species richness of ladybird beetles on these two islands based on our field surveys and the literature data. As expected, clearly more ladybird species have been recorded on Tenerife (47 species) than on La Gomera (26 species). Being the largest of the Canary Islands, Tenerife has the richest ladybird fauna of all the islands in the archipelago, but it is also more susceptible to colonization by non-native ladybirds than the other islands: to date, ten species of non-native ladybirds have been recorded on Tenerife, compared to between three and seven on the other islands (five on La Gomera). Among the non-native ladybirds established on Tenerife (but not on any other island in the archipelago) is the harlequin ladybird (Harmonia axyridis), a highly invasive species of Asiatic origin that has spread nearly worldwide. This paper provides new data on the ladybird beetles (Coccinellidae) from two islands in the Canary archipelago: Tenerife, the largest island, and La Gomera, the second smallest. As they clearly differ in size but are similar in location and geological age, they are a suitable model for testing the species–area relationship. Our study shows that, in line with this main assumption of the theory of island biogeography, clearly more species occur on a large island (Tenerife) than on a small one (La Gomera). The field surveys documented the occurrence of 35 ladybird species on Tenerife (including 5 not previously reported from this island) and of 20 species on La Gomera (2 species new to the island). Coelopterus sp. collected on Tenerife (a single female that could not be identified to species) is the first record of this genus for the whole Canary Islands. Taking our data and previously published records into account, 47 species of Coccinellidae are known to occur on Tenerife and 26 species on La Gomera. Tenerife has by far the richest ladybird fauna of all the Canary Islands (the next in line, Gran Canaria, has 41 recorded species), but it also has the highest number of non-native ladybird species. All of the ten non-native species recorded in the Canary Islands are found on Tenerife, and for most of them, Tenerife was the island of their first appearance in the archipelago. This island, much more distant from the mainland than the other relatively large islands (Fuerteventura, Lanzarote), appears to be the main recipient of ladybirds immigrating to the Canary Islands. Tenerife can play this role probably because of its great habitat diversity and altitude variation, as well as intensive tourism and trade-related transport. [ABSTRACT FROM AUTHOR]

In this paper, we introduce LagunAR, a mobile outdoor Augmented Reality (AR) application for providing heritage information and 3D visualization on a city scale. The LagunAR application was developed to provide historical information about the city of La Laguna in the XVI century, when it was the main city in the Canary Islands. The application provides a reconstructed 3D model of the city at that time that is shown on a mobile phone over-imposed on the actual city using geolocation. The geolocated position is used also for providing information of several points of interest in the city. The paper describes the design and implementation of the application and details the optimization techniques that have been used to manage the full information of the city using a mobile phone as a sensor and visualization tool. We explain the application usability study carried out using a heuristic test; in addition it is probed by users in a qualitative user test developed as preliminary research. Results show that it is possible to develop a real-time application that shows the user a city-scale 3D model and also manages the information of the points of interest. [ABSTRACT FROM AUTHOR]

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]

Simple Summary: The ladybird beetle fauna of the Canary Islands is quite specific due to the presence of a number of species that do not occur anywhere else (the so-called endemic species). However, many ladybirds recorded in the archipelago are relatively recent arrivals from various parts of the world, as shown by our previous surveys carried out in several of the Canary Islands, including Fuerteventura, Lanzarote, Gran Canaria, and El Hierro. In this paper, we analyze the ladybird fauna of La Palma, one of the western islands of the archipelago, based on our field survey and already published data. The survey resulted in the recording of 26 species, seven of which had not previously been recorded on La Palma, and two of these seven had not been recorded on any of the Canary Islands. Combining our data and literature reports gives a figure of at least 35 ladybird species recorded to date on La Palma. This is fewer than on the central islands of the Canary archipelago (Gran Canaria and Tenerife), but more than on the other four islands (Fuerteventura, Lanzarote, La Gomera, and El Hierro). This study confirms previous observations that the Canary Islands are often colonized by exotic ladybird species. This paper provides new data on the ladybird beetles (Coccinellidae) of La Palma, one of the western islands of the Canarian archipelago. The field survey of 54 study sites resulted in recording 2494 ladybird individuals belonging to 26 species. Seven of the species recorded were new to La Palma, including two, Harmonia quadripunctata (Pontoppidan) and Nephus reunioni (Fürsch), which were not registered so far on any of the Canary Islands. Novius conicollis (Korschefsky) is synonymized with N. cruentatus (Mulsant). Taking our survey and literature reports into account, a total of at least 35 species of Coccinellidae have so far been recorded on La Palma. This richness in species is lower compared to that of the central islands of the Canarian archipelago, Gran Canaria (42 species) and Tenerife (41 species), but higher than that of the remaining four islands (between 22 and 27 species). The detection of two alien species new to La Palma, Nephaspis bicolor Gordon and Nephus reunioni (Fürsch), confirms earlier observations that colonization of the Canary Islands by ladybird species of exotic origins seems to be a frequent phenomenon. [ABSTRACT FROM AUTHOR]

Seagrass and seaweed meadows hold a very important role in coastal and marine ecosystems. However, anthropogenic impacts pose risks to these delicate habitats. This paper analyses the multitemporal impact of the construction of the largest industrial port in the Canary Islands, near the Special Area of Conservation Natura 2000, on Cymodocea nodosa seagrass meadows (sebadales) of the South of Tenerife, in the locality of Granadilla (Canary Islands, Spain). Very-high-resolution WorldView-2 multispectral satellite data were used for the analysis. Specifically, three images were selected before, during, and after the construction of the port (2011, 2014, and 2022, correspondingly). Initially, advanced pre-processing of the images was performed, and then seabed maps were obtained using the machine learning K-Nearest Neighbors (KNN) supervised classification model, discriminating 12 different bottom types in Case-2 complex waters. The maps achieved high-quality metrics with Precision values of 85%, 81%, and 80%, recall of 76%, 77%, and 77%, and F1 scores of 80%, 79%, and 77% for 2011, 2014, and 2022, respectively. The results mainly show that the construction directly affected the seagrass and seaweed habitats. In particular, the impact of the port on the meadows of Cymodocea nodosa, Caulerpa prolifera, and maërl was assessed. The total maërl population was reduced by 1.9 km2 throughout the study area. However, the Cymodocea nodosa population was maintained at the cost of colonizing maërl areas. Furthermore, the port sedimented a total of 0.98 km2 of seabed, especially Cymodocea nodosa and maërl. In addition, it was observed that Caulerpa prolifera was established as a meadow at the entrance of the port, replacing part of the Cymodocea nodosa and maërl areas. As additional results, bathymetric maps were generated from satellite imagery with the Sigmoid model, and the presence of a submarine outfall was, as well, presented. [ABSTRACT FROM AUTHOR]

This study uses an inbound measuring instrument to segment the cellar's e-commerce in the Canary Islands. One of the central claims of this paper is that inbound marketing comprises several dimensions such as content resources, SEO, social media, digital maturity, and e-commerce growth, such that it implies superior levels of personalisation, flexibility, service, security, and privacy, product and shop transparency, advanced technology, and data mining. After raising three research questions, this study performed fieldwork based on web analytics procedures, extracting metrics from 59 cellars' websites thanks to employing a broad range of software. The sampling procedure was non-probabilistic and judgmental, took place in the spring of 2023, and gathered relevant metrics to build an inbound scale. The data prove that the inbound measuring instrument can rank and segment the Canary Islands' marketplace. Although this study has put forward a tentative explanation and application of the inbound marketing notion and tools, findings suggest a need for a more significant effort to explore how generalizable the created measuring instrument is. [ABSTRACT FROM AUTHOR]

The use of renewable energy for desalination started in the 1980s, in order to provide a sustainable water supply in windy/sunny areas with water shortages. Nevertheless, this initiative has been generally limited to the R&D field and prototypes, with few units operating under real conditions. The research tradition in this field carried out by the Canary Islands Institute of Technology, based on pilot facilities, resulted in wide expertise on practical issues, as well as a deep knowledge on the state of the art. This paper deals with the most relevant technical aspects to be considered in the optimal design and operation of wind/photovoltaic (PV)-powered reverse-osmosis (RO) systems, focusing on practical indications: appropriate pre-treatment, the use and selection of the RO energy recovery system (ERD), the selection of an energy storage system, key recommendations for the O&M actions in wind- and PV-powered RO systems (extracted from the experience of operating different units in remote locations (PV and RO) and coastal areas (wind and RO)), and an identification of the pros and cons of hybrid systems. A selection of economic data is given, indicating the main aspects of the minimization of the cost of water. Finally, the paper mentions the latest advances in the involved technologies. [ABSTRACT FROM AUTHOR]

An intertidal sandstone reef, named barra de Las Canteras, protects the western coast of Las Palmas de Gran Canaria city (Canary Islands, Spain). The beach-reef system of Las Canteras constitutes one of the most valuable coastal geomorphological sites in the archipelago. Stratigraphic studies have identified the formation of the reef in the Last Interglacial (MIS 5e) in a coastal sedimentary paleo-environment. The rock structure is highly exposed to the Atlantic swell and consists mainly of a sandstone beachrock with a medium resistance to erosional processes. However, the historical and current erosion rates and the original extent of the reef are not known to date. This paper explores the geomorphological structure of the reef by combining a topo-bathymetric analysis (obtained by differential GPS, multibeam echosounder and hyperspectral sensor) and the analysis of geomorphological features on high-resolution images, obtained with a hyperspectral camera mounted on a UAV. The results provide a comprehensive, high-resolution image of the subaerial and submerged morphology of the reef. The structure reflects the distribution of erosional fronts and the existence of collapsing submarine blockfields and nearshore, uneroded, remnant reliefs. Detailed analysis of these features allows to estimate the probable original extent of the sandstone reef and to relate the erosional retreat processes to the sea-level dynamics during the Holocene. [ABSTRACT FROM AUTHOR]

Canary Island date palms (Phoenix canariensis) have been planted as a landscaping feature plant throughout warm, temperate, and subtropical climates. The physical amenity provisioning of this species (shade effects, microclimate amelioration, water usage, etc.) has so far not been systematically assessed. This paper reports on temperature and humidity measurements in both a suburban and a rural location in SE Australia. The study demonstrates the effects of the palm canopy as regulator of humidity and provider of shade and, thus, amenity values in urban landscape settings. Drawing on published energy savings and growth requirements of the plant, the paper argues that Canary Island date palms are landscaping plants suitable to ameliorate the microclimate in urban neighborhoods with varied socio-economic conditions. [ABSTRACT FROM AUTHOR]

In this study, the main elements that can make up a Natural Treatment System for Wastewater (NTSW), its most important parameters and properties of operation and design, have been analyzed, as well as the environmental problems derived from the generation of large amounts of slurry. The objective of this paper is to propose a methodology to improve the operation of these systems, associated with small and medium-sized livestock farms, in insular and isolated systems such as the Canary Islands. An Integrated and Resilient System (IRS) for monitoring and measuring operational variables quasi-continuous and in situ is proposed. Low-cost technology and open source hardware are employed, as well as application of the IoT (Internet of Things) strategies to share and analyze the information collected in the cloud. In view of the high degree of resilience and the simplicity of this type of technology, as well as its low cost, it is concluded that it is feasible to create a measurement system with these characteristics that can be used for NTSW parameterization, and other purposes. Satisfactory results were obtained for several parameters (ambient temperature, relative humidity, UV radiation, atmospheric pressure). It is presented as a novel proposal based mainly on low-cost technology and free software with which to improve the NTSW operation process. [ABSTRACT FROM AUTHOR]

The existence of aviation subsidies can exacerbate congestion in airports that operate near their maximum threshold. One of the main operational issues in airports, that is, aircraft taxiing operations, could become more difficult and, therefore, produce negative effects on airport capacity management. Air carrier economies, touristic mobility (leisure travel), and the environment could also be negatively affected. Greenhouse gas emissions, passenger travel time, and air carriers' fuel costs, for example, might rise due to aircrafts' increased taxiing time. This paper seeks to analyse the impact of regional aviation subsidies for regional hub airports in the Canary Island air traffic network; specifically, the effect it has on airports' capacity in terms of LTO (landing and taking off) cycle delays and its repercussions for passenger travel time, air carrier economics, and the environment. Therefore, to quantify the extent that the increased traffic from subsidies cause airport ground operations to delay flights, the disturbance between aircraft categories in landing and taking off operations must be considered. The disturbance between aircrafts will be evaluated by employing a simple model of landing intervals considering two aircraft categories (i.e., ATRs-72, ATRs-42, and B737/A320 aircraft families). The above-mentioned methodology provides an approximation of the average processing rate for take-off using the ultimate capacity concept for a variety of aircrafts landing on a single runway of the airport. As a result, it must be noted that there is a potential economic and environmental impact associated with the implementation of the subsidy increase for residents' interisland travel and from the Canary Islands to the mainland. There is also a negative effect on runways for both airports due to the capacity constraints. These impacts, however, have to be balanced with the social and economic benefits that each regional inhabitant derives from the subsidy in terms of improvement of their mobility for any purpose. [ABSTRACT FROM AUTHOR]

This paper analyses the profile of individuals who decide to purchase a Sport Utility Vehicle (SUV) in a medium-sized isolated island system such as Tenerife Island. To achieve this objective, we used a survey conducted in 2017 to identify the characteristics of the individuals most likely to choose an SUV or another type of vehicle or be undecided. Subsequently, a discrete choice model was estimated to assess the probability that an individual chooses one of the three options as a function of their socio-economic characteristics, mobility routines, vehicle attributes and psychosocial traits. The results show the need to adopt energy policy measures related to vehicle choice, as they put the fulfilment of the decarbonization objectives for the energy transition in the Canary Islands at risk. Firstly, the authorities should carry out campaigns to achieve a more environmentally conscious behaviour by highlighting the higher consumption and emission levels of this type of vehicle. Secondly, subsidies for more efficient new vehicles and taxation should promote the purchase of low-emission vehicles to compensate for the greater willingness to pay of SUV buyers. In particular, purchase taxation should be linked to emission levels rather than only considering power, engine characteristics or labelling. [ABSTRACT FROM AUTHOR]

This paper presents a tidal current meter that is based on the inertial acceleration principle for offshore infrastructures in deep water. Focusing on the marine installations of the aquaculture industry, we studied the forces of tides at a depth of 15 m by measuring the acceleration. In addition, we used a commercial MEMS triaxial accelerometer to record the acceleration values. A prototype of the tidal measurement unit was developed and tested at a real offshore aquaculture infrastructure in Gran Canaria, which is one of the Canary Islands in the Atlantic Ocean. The proposed tidal measurement unit was used as a recorder to assess the complexity of measuring the frequency of tidal currents in the short (10 min), medium (one day) and long term (one week). The acquired data were studied in detail, in both the time and frequency domains, to determine the frequency of the forces that were involved. Finally, the complexity of the frequency measurements from the captured data was analyzed in terms of sampling ratio and recording duration, from the point of view of using our proposed measurement unit as an ultra-low-power embedded system. The proposed device was tested for more than 180 days using a lithium-ion battery. This working period was three times greater than the best alternative in the literature because of the ultra-low-power design of the on-board embedded system. The measurement accuracy error was lower than 1% and the resolution was 0.01 cm/s for the 0.8 m/s velocity scale. This performance was similar to the best Doppler solution that was found in the literature. [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]

This paper's primary objective is to segment the online marketplace of the Canary Islands' museums by using different conversion funnel metrics. Little systematic research exists on digital user behaviour, and much less is known about how to segment cultural users with structured data from manually extracted and SEO software sources. With this aim in mind, we built a database with data related to the different phases of the conversion funnel of the museums to segment this online museum marketplace. In the findings, not only do we acknowledge the existence of different segments, but we also provide insight into the user's digital behaviour by considering different metrics from the different phases of the conversion model process (awareness, consideration, conversion and loyalty). The originality of this paper is multifold. Firstly, it estimates the potential optimisation of these websites to improve the digital marketing implemented by the museum sector of the Canary Islands. Secondly, it sheds light on what benchmarking tactics and statistics procedures can be followed to carry out a non-hierarchical segmentation with standardised and comparable data. Thirdly, it contributes to the literature of digital marketing by eclectically combining the conversion funnel model, benchmarking techniques and non-hierarchical segmentation procedures. [ABSTRACT FROM AUTHOR]

Featured Application: Analysis of monitoring data from very slow-moving landslides. This paper presents a methodological approach to the time-series analysis of movement monitoring data of a large slow-moving landslide. It combines different methods of data manipulation to decrease the subjectivity of a researcher and provides a fully quantitative approach for analyzing large amounts of data. The methodology was applied to 3D dilatometric data acquired from the giant San Andrés Landslide on El Hierro in the Canary Islands in the period from October 2013 to April 2019. The landslide is a creeping volcanic flank collapse showing a decrease of speed of movement during the monitoring period. Despite the fact that clear and unambiguous geological interpretations cannot be made, the analysis is capable of showing correlations of the changes of the movement with increased seismicity and, to some point, with precipitation. We consider this methodology being the first step in automatizing and increasing the objectivity of analysis of slow-moving landslide monitoring data. [ABSTRACT FROM AUTHOR]

Food security concerns, climate change impacts, and increased pressure on conventional water resources have encouraged the agricultural use of nonconventional water resources in the last decade. As a result, desalinated seawater (DSW) has already consolidated its position as an alternative source to increase the supply for crop irrigation in Spain and Israel, where farmers' acceptance is progressively on the rise. The first experiences in these regions highlighted that DSW agricultural use involves new agronomic, economic, and environmental challenges which require innovative research approaches and imply novel water management strategies. In this Special Issue, eight high-quality papers which present current research trials and study cases, covering a wide range of topics that are relevant when irrigating with DSW, have been selected. The papers came from the three regions of the world that currently have a massive agricultural DSW supply: Southeastern Spain, Israel, and the Canary Islands. [ABSTRACT FROM AUTHOR]

Tourism is one of the economic sectors that contributes the most to the gross domestic product in many countries, moving, in turn, other economic sectors such as transport. In particular, the automotive industry constitutes an economic subsector that moves vast amounts of money. Concerning tourism and transport sectors, car rental is a crucial element contributing considerably to gross domestic product and job creation. Due to the effects that vehicle rental seems to have on various economic sectors, it seems interesting to know why a tourist chooses to rent a car during their vacation in a specific destination. This work aims to study those factors that can be considered relevant and affect the probability of renting a vehicle. The document addressed the following research topics: (a) identifying significant variables; and (b) can information on these factors help car rental firms? Empirically, it is shown that more tourists do not rent a car and this fact has to be considered. Thus, the classical logistic and Bayesian regression models do not seem adequate in this case, so that the authors will consider an asymmetric logistic regression model. This work analyzes 28,235 tourists who visited the Canary Islands during 2017. From a Bayesian point of view, asymmetric logistics regression is chosen as the best model because it detects relevant development factors not seen by standard logistic regressions. In light of the document's findings, various practice recommendations improve decision-making in this field. The asymmetric logit link is a helpful device that can help rental companies make decisions about their clients. [ABSTRACT FROM AUTHOR]

The apothecial fungus Ramomarthamyces octomerus sp. nov. is described from specimens collected in Mediterranean climate regions in southern Portugal, Spain (Canary Islands), and the Dalmatian region of Croatia. Presumably saprobic, R. octomerus occurs on intact, decorticated wood of Laurus novocanariensis and Olea europaea. Ascospores are cylindric-ellipsoid and seven-septate. Surprisingly, in our four-locus phylogenetic analysis (nuSSU, ITS1-5.8S-ITS2, LSU, mtSSU), this fungus clusters among species of Cyclaneusma, Marthamyces, Naemacyclus, and Ramomarthamyces in a core Marthamycetaceae clade that circumscribes primarily leaf-inhabiting, filiform-spored species. In addition, the asci of R. octomerus possess an amyloid pore, but the reaction varies between specimens collected in the Canary Islands and those collected in Portugal and Croatia. The occurrence of an amyloid reaction in the asci of R. octomerus challenges the characterization of Marthamycetales taxa as possessing inamyloid asci. In our discussion we provide background and analysis of these notable observations. [ABSTRACT FROM AUTHOR]

Water deficit in semi-arid regions limits the future of the livestock sector. Also, its high price represents a percentage of the total cost of forage production. Non-conventional water resources applied by subsurface drip irrigation (SDI), in which the safe use lies in the management and not on the level of water treatment, would enhance the ruminant production sustainability. To obtain the optimal benefit, the transformation of water per kilogram of dry matter produced must have a high grade of effectiveness. Under this premise, a maralfalfa crop (Penissetum sp, hybridum) has been established with an SDI system and reclaimed water. Forage yield is analyzed with respect to a 40% irrigation reduction. This study shows that, with the use of these good irrigation management practices, it is possible to harvest an annual production of 90 to 72 t·ha-1 in the warmer regions of the Canary Islands. This implies water consumption between 13,200 and 8100 m3·ha-1. A water consumption of 21,000 m3·ha-1 per year for the same production, at a ratio of 230 L.t-1, can be estimated for the rest of the Canary Islands coastal regions. The use of the water management described in this paper can be profitable in the Canary Islands for fodder production. [ABSTRACT FROM AUTHOR]

Simple Summary: Many plants and animals that live in the Canary Islands belong to the so-called endemic species, i.e., they do not occur outside of this particular region. Several other species have a slightly wider geographical distribution, apart from the Canaries, which also includes some islands of the nearby archipelagos, such as Madeira or the Azores, or the northwestern periphery of Africa. Here, we call such species subendemics. However, the Canary Islands have recently been colonized by a substantial number of immigrants from more or less remote areas. In this paper, based on our field survey and previously published data, we analyzed the fauna of the ladybird beetles (Coccinellidae) of Gran Canaria, one of the central islands of the archipelago. Among 42 ladybird beetle species so far recorded on this island, 17 (40%) are endemics and subendemics, and 21 (50%) probably arrived in Gran Canaria relatively recently, i.e., in the 20th and 21st century. Of those newcomers, there are Australian, American, African, and European species. The nonnative ladybird species may pose a threat to the unique ladybird communities from Gran Canaria and other islands of the archipelago. Research on the fauna of beetles (Coleoptera) of the Canary Islands has a long tradition, which enables tracking changes in their species composition and arrival of new species. In this paper, we provide new faunistic data on the ladybird beetles (Coccinellidae) recorded on Gran Canaria, one of the central islands of the archipelago, and then analyze available information on the Gran Canarian ladybird fauna from geographical and historical points of view. The field survey resulted in recording 1402 ladybird individuals belonging to 30 species. Ten of these species were new to Gran Canaria and three of them, Chilocorus bipustulatus (Linnaeus), Nephus bisignatus (Boheman), and Nephus ulbrichi Fürsch, had not previously been reported to be on any of the islands of the Canarian archipelago. Tetrabrachys tinerfensis (Hodgson) is synonymized with T. deserticola (Wollaston). Our survey and literature reports allowed us to recognize 42 species of Coccinellidae so far recorded on Gran Canaria. Seventeen of them (40%) belonged to the Canarian endemic and subendemic species, and 21 (50%) were newcomers and presumed newcomers. Colonization of Gran Canaria and other islands of the archipelago by ladybird species of various origins seems to be a frequent phenomenon that may pose a threat to the unique communities of the native Canarian species. [ABSTRACT FROM AUTHOR]

The vegetation of the Canary Islands is characterized by a large number of endemic species confined to different altitudinal levels. It can be assumed that these circumstances determine the characteristic features of the chemical composition of local beekeeping products, including propolis. We report, for the first time, the chemical composition of propolis from Tenerife (Canary Islands). The volatile emissions of three propolis samples collected from different apiaries are represented by 162 C1–C20 compounds, of which 144 were identified using the HS-SPME/GC-MS technique. The main group of volatiles, consisting of 72 compounds, is formed by terpenoids, which account for 42–68% of the total ion current (TIC) of the chromatograms. The next most numerous groups are formed by C6–C17 alkanes and alkenes (6–32% TIC) and aliphatic C3–C11 carbonyl compounds (7–20% TIC). The volatile emissions also contain C1–C6 aliphatic acids and C2–C8 alcohols, as well as their esters. Peaks of 138 organic C3–C34 compounds were recorded in the chromatograms of the ether extracts of the studied propolis. Terpene compounds form the most numerous group, but their number and content in different samples is within very wide limits (9–63% TIC), which is probably due to the origin of the samples from apiaries located at different altitudes. A peculiarity of the chemical composition of the extractive substances is the almost complete absence of phenylcarboxylic acids and flavonoids, characteristic of Apis mellifera propolis from different regions of Eurasia and North America. Aromatic compounds of propolis from Tenerife are represented by a group of nine isomeric furofuranoid lignans, as well as alkyl- and alkenyl-substituted derivatives of salicylic acid and resorcinol. [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]

The analysis of energy consumption in reverse osmosis desalination plants is the most important and relevant factor to study, because this parameter indicates the level of efficiency and competitiveness of the plant. The direct consequence of the high specific energy consumption (SEC) of a desalination plant in the production of water is one of the main obstacles to the exponential expansion of this technology worldwide. The methodological procedure used to carry out the work is based on the analysis of energy consumption, maintenance costs, staff, membranes, and reagents of three desalination plants with a production of more than 23,000 m3/day located in the Canary Islands (Spain); all data are obtained from real analyses collected "in situ" from 2015 to 2018. One of the main objectives of the current research on desalination plants is to reduce the SEC of seawater desalination plants (SWRO), incorporating energy recovery systems (ERS) and high efficiency pumps (HEP), and to implement different operational configurations with the aim of minimizing the energy requirements necessary to obtain a good product quality at minimum production cost. [ABSTRACT FROM AUTHOR]

Coronilla viminalis Salisb. is a fodder leguminous plant from the Canary Islands and Northwestern Africa with adaptation to drought. Its conservation status is critical. Its low germination capacity and intense loss of viability of the seeds over time complicate its conservation, limiting its long-term maintenance in germplasm banks and hampering its potential use as a resilient fodder crop. Therefore, in this work, two alternative propagation methods have been addressed. The first was based on facilitating seed germination under aseptic conditions, supplementing the media with gibberellic acid (GA3). The latter consisted of creating a micropropagation method from nodal segments and testing different media and pretreatments with indole-3-acetic acid (IAA). The quantity and quality of the roots were assessed, and the plant acclimation rate was measured. The results showed that the optimum concentration of GA3 for germination, up to 98%, was 250 PPM. The experiments showed that using IAA in the micropropagation media is critical for in vitro rooting in this species. A hormonal pretreatment with IAA significantly improved the rooting efficiency compared to supplementing it into the culture media. One hundred percent of acclimated plants survived the process. These new protocols will help conserve the species and explore its possibilities as fodder crops. [ABSTRACT FROM AUTHOR]

The Canary Islands are considered a hotspot of biodiversity and have high levels of endemicity, including endemic reptile species. Nowadays, some invasive alien species of reptiles are proliferating with no control in different parts of the territory, creating a dangerous situation for the ecosystems of this archipelago. Despite the fact that the regional authorities have initiated actions to try to control the proliferation of invasive species, the problem has not been solved as it depends on sporadic sightings, and it is impossible to determine when these species appear. Since no studies for automatically identifying certain species of reptiles endemic to the Canary Islands have been found in the current state-of-the-art, from the Signals and Communications Department of the Las Palmas de Gran Canaria University (ULPGC), we consider the possibility of developing a detection system based on automatic species recognition using deep learning (DL) techniques. So this research conducts an initial identification study of some species of interest by implementing different neural network models based on transfer learning approaches. This study concludes with a comparison in which the best performance is achieved by integrating the EfficientNetV2B3 base model, which has a mean Accuracy of 98.75%. [ABSTRACT FROM AUTHOR]

The future success of wave energy in the renewable energy mix depends on the technical advancements of the specific components and systems, on the grid access availability and, ultimately, on the economical profitability of the investment. Small and remote islands represent an ideal framework for wave energy exploitation, due both to resource availability and to the current high cost of electricity that mostly relies on diesel generation. Energy storage can be the enabling technology to match the intermittent power generation from waves to the energy needs of the local community. In this paper real data from La Palma, in the Canary Islands, are used as a basis for the considered test case. As a first step the study quantifies the expected power production from Wave Energy Converter (WEC) arrays, based on data from the Lifesaver point absorber developed by Fred. Olsen. Then, a stochastic optimization approach is applied to evaluate the convenience of energy storage introduction for reducing the final cost of energy and to define the corresponding optimal rating of the storage devices. [ABSTRACT FROM AUTHOR]

In this paper we describe a fast, specialized hardware implementation of the belief propagation algorithm for the CAFADIS camera, a new plenoptic sensor patented by the University of La Laguna. This camera captures the lightfield of the scene and can be used to find out at which depth each pixel is in focus. The algorithm has been designed for FPGA devices using VHDL. We propose a parallel and pipeline architecture to implement the algorithm without external memory. Although the BRAM resources of the device increase considerably, we can maintain real-time restrictions by using extremely high-performance signal processing capability through parallelism and by accessing several memories simultaneously. The quantifying results with 16 bit precision have shown that performances are really close to the original Matlab programmed algorithm. [ABSTRACT FROM AUTHOR]

In this paper we show a fast, specialized hardware implementation of the wavefront phase recovery algorithm using the CAFADIS camera. The CAFADIS camera is a new plenoptic sensor patented by the Universidad de La Laguna (Canary Islands, Spain): international patent PCT/ES2007/000046 (WIPO publication number WO/2007/082975). It can simultaneously measure the wavefront phase and the distance to the light source in a real-time process. The pipeline algorithm is implemented using Field Programmable Gate Arrays (FPGA). These devices present architecture capable of handling the sensor output stream using a massively parallel approach and they are efficient enough to resolve several Adaptive Optics (AO) problems in Extremely Large Telescopes (ELTs) in terms of processing time requirements. The FPGA implementation of the wavefront phase recovery algorithm using the CAFADIS camera is based on the very fast computation of two dimensional fast Fourier Transforms (FFTs). Thus we have carried out a comparison between our very novel FPGA 2D-FFTa and other implementations. [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]

Highlights: What are the main findings? The presence of marine litter in sublittoral areas is determined by the density of coastal tourist territories and is lower in areas predominantly used for tourism versus those of mostly resi-dential use; Data collection methodology using depth line transects is essential for estimating marine litter density; The presence of macro debris from motor vehicle tyres is independent of urban areas and their associated density and is also unrelated to maritime access. What are the implications of the main finding? The density of coastal tourist territories plays a crucial role in determining the possible presence of marine litter in sublittoral areas and developing specific preventive policies; It is not possible, with current technology, to use remote means of complex surface and bottom collection of marine litter without depth transects; The deposition of a characteristic type of marine litter, used tyres, shows patterns of occurrence totally independent of coastal urban density. The coastal strip, characterized by the urbanization of coastal tourist territories (CTTs), has expanded over decades through civil engineering, altering the shoreline dynamics and creating artificial beaches crucial for tourism. To examine the relationship between extensive land use in CTTs for tourism and residences and the presence of marine litter, a specific parametric study was conducted along the coast of Tenerife, the largest island in the Canary Islands. Due to Tenerife's geographical location and exposure to the descending Gulf Stream flow, the coastal waters in the selected zone experience waste impact at both local and global scales. However, the presence of marine litter deposited by ocean currents is at a micro level and falls outside the scope of this report. This study parameterised urban reality in study areas, and the presence of macro waste has been parameterised using standardised units of measurement. This enables the establishment of source measurements that will contribute to preventative measures against this type of coastal pollution. The interdependence between tourist zoning, civil seafront engineering works along the seafront, and marine litter presence in inaccessible and visible areas for tourists requires a methodology to better understand waste origin and loading areas. This knowledge is crucial for an effective local monitoring system. A quantitative overlay reading methodology has been designed in the urban setting through calculations of urban densities, while examining the waste in these areas' immediate infralittoral flooring through the use of visual underwater extraction. Anticipating the type and quantity of waste in each area will allow for the implementation of effective awareness, promoting action for preventative and corrective measures at the urban level. The results show a direct dependence between urban density and the presence of waste, as well as an equation that makes it possible to anticipate the amount of waste according to urban density and its relational vector. There is no discontinuity between them, as each area is affected by others to the extent that they establish the parametric continuity conditions determining each field. Therefore, it is possible to relate them beyond a one-on-one relationship. This approach fosters sustainable tourism development, reducing pressure on the sea and enhancing the utilisation of tourism revenues in measures to address waste-related challenges and promotes sustainable tourism development in Europe's coastal regions. [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]

A fungal endophyte originating from the Canary Islands was identified as a potent antagonist against the fungal phytopathogen Hymenoscyphus fraxineus, which causes the devastating ash dieback disease. This endophyte was tentatively identified as Pezicula cf. ericae, using molecular barcoding. Isolation of secondary metabolites by preparative high-performance liquid chromatography (HPLC) yielded the known compounds CJ-17,572 (1), mycorrhizin A (3) and cryptosporioptides A–C (4–6), besides a new N-acetylated dihydroxyphenylalanin derivative 2, named peziculastatin. Planar structures were elucidated by NMR and HRMS data, while the relative stereochemistry of 2 was assigned by H,H and C,H coupling constants. The assignment of the unknown stereochemistry of CJ-17,572 (1) was hampered by the broadening of NMR signals. Nevertheless, after semisynthetic conversion of 1 into its methyl derivatives 7 and 8, presumably preventing tautomeric effects, the relative configuration could be assigned, whereas comparison of ECD data to those of related compounds determined the absolute configuration. Metabolites 1 and 3 showed significant antifungal effects in vitro against H. fraxineus. Furthermore, 4–6 exhibited significant dispersive effects on preformed biofilms of S. aureus at concentrations up to 2 µg/mL, while the biofilm formation of C. albicans was also inhibited. Thus, cryptosporioptides might constitute a potential source for the development of novel antibiofilm agents. [ABSTRACT FROM AUTHOR]

The incorporation of digital didactic materials into the teaching and learning process of students, both in Early Childhood and Primary Education, inevitably entails changes. Some of them concern teacher training, others the interactions and roles of the members of the educational community, and others the innovation, a priori, of the educational process itself. In this context, characterized by the digitization of classrooms, questions arise that this research aims to answer: What vision do teachers have of the incorporation of these media? In what learning situations are they used and for what purposes? Are there differences between the use of digital resources in the infant and primary school stages? This article aims to analyze and compare the perceptions of teachers in two different contexts: the Autonomous Community of the Canary Islands and the Valencian Community. By means of a qualitative study, the focus is on knowing the teachers' assessment of the usefulness of these resources and on identifying the uses given to them in classroom practices. The results show how, despite the widespread use of digital materials in both stages, some teachers are rethinking their use with students at an early age. [ABSTRACT FROM AUTHOR]

Simple Summary: Date stone beetles tunnel into the seeds of several palm species, where they establish brood galleries in which they spend their entire life cycle. Their larvae, which consume the seed's albumen, pupate and hatch in the seed, with multiple generations co-existing until all the seed's albumen has been consumed. Little is known about the initial tunneling and nature of the establishment of the brood galleries. Through experimentation with seeds of the Canary Islands Date Palm, this study shows that the beetles exhibited an overwhelming preference for a penetration at the grooved side. Behavioral observations showed that, in order to penetrate, the date stone beetle needs to be able to push its mandibles into the epicarp of the seed. The main thrust is generated by the hind legs which requires traction as provided by the groove. When tunneling, the mid legs function as a pivot, while the fore legs enable lateral control. When in the tunnel cavity the pair of mid legs act as wall anchors. Gustatory cues prevent the beetle from tunneling through to the other side. The nature of these gustatory cues remains unclear at this point and awaits future research. The cryptic spermatophagus date stone beetle (Coccotrypes dactyliperda Fabricius, 1801) tunnels into palm seeds for oviposition and subsequent establishment of brood galleries. Based on behavioral observations this paper describes the biomechanical and gustatory parameters that govern the initial excavation of the tunnels and the subsequent establishment of the galleries. When tunneling into Canary Islands Date Palm (Phoenix canariensis Chabaud, 1882) seeds, penetration principally occurs at the dorsal side of the seed, in particular the groove, which allows the beetle to gain the required traction. Tunneling is executed in a circular fashion with clockwise or counter-clockwise repositioning in approximately one-eighth to one-quarter turns. Biomechanically, the three pairs of legs provide thrust (hind legs), pivoting (mid legs), and lateral control (fore legs). Gustatory cues, the nature of which remains unclear at this point, prevent the beetle from tunneling through to the other side. [ABSTRACT FROM AUTHOR]

Cumbre Vieja volcano, located in La Palma Island (Canary Islands, Spain), erupted on 19 September 2021. Some papers have been published in the past in which the tsunamis generated by a potential massive landslide due to a collapse of one of the volcano flanks are investigated. However, a potential slide of the lava flow down the island slope has not been considered yet. A numerical model has been applied to simulate the propagation of the tsunami generated by such slide and to assess its consequences in the near field (Canary Islands and west coast of Africa). The model provides maps of maximum wave heights and arrival times of the tsunami, as well as time series of water surface elevation at several selected locations. Since the volume involved in such potential slide is a priori not known, several values were tested and their effects compared. [ABSTRACT FROM AUTHOR]

Simple Summary: Cardiopulmonary dirofilariasis is a vector-borne zoonotic disease caused by the nematode parasite Dirofilaria immitis. This disease is cosmopolitan and mainly affects canids and felids and accidentally humans. The Canary Islands (Spain) are considered an endemic area and some of its islands such as the islands of Tenerife and Gran Canaria (provincial capitals) are considered hyperendemic. The aim of our study was to develop a quantitative proposal of the risk of infection by D. immitis using an ecological niche model (ENM), taking into account environmental and bioclimatic variables that affect the presence of culicid mosquitoes, to maximize its resolution and, in addition, estimate the impact of future climatic conditions in 2080 on the risk of infection. Nineteen environmental and bioclimatic variables were processed and modeled using ArcMap 10 and MaxEnt 3.4. The model was weighted by the number of Dirofilaria spp. generations and validated with the prevalence and geolocation of D. immitis-infected dogs across the Canary Islands. The risk map of D. immitis infection in the Canary Islands is high in all the islands, except for the higher altitude areas, and as for the analysis of range change, the projection for 2080 does not show a large increase in the extension of areas suitable for Culex spp., but rather a modification in the distribution of these areas. This model will help veterinary and public health professionals to carry out more effective and localized prevention and control of cardiopulmonary dirofilariosis (heartworm disease). Heartworm disease is a vector-borne zoonotic disease caused by Dirofilaria immitis. The Canary Islands (Spain), geolocated close to the coast of Western Sahara, is an archipelago considered hyperendemic where the average prevalence in domestic dogs is high, heterogeneous, and non-uniform. In addition, Culex theileri has been reported as a vector of the disease on two of the most populated islands. Our aim was to develop a more accurate transmission risk model for dirofilariosis for the Canary Islands. For this purpose, we used different variables related to parasite transmission; the potential distribution of suitable habitats for Culex spp. was calculated using the ecological niche model (ENM) and the potential number of generations of D. immitis. The resulting model was validated with the geolocation of D. immitis-infected dogs from all islands. In addition, the impact of possible future climatic conditions was estimated. There is a risk of transmission on all islands, being high in coastal areas, moderate in midland areas, and minimal in higher altitude areas. Most of the dogs infected with D. immitis were geolocated in areas with a high risk of transmission. In 2080, the percentage of territory that will have been gained by Culex spp. is small (5.02%), although it will occur toward the midlands from coastal areas. This new model provides a high predictive power for the study of cardiopulmonary dirofilariosis in the Canary Islands, as a hyperendemic area of the disease, and can be used as a tool for its prevention and control. [ABSTRACT FROM AUTHOR]

This study presents the results of the long-term monitoring of PM10 and PM2.5 concentrations using a low-cost particle sensor installed in a suburban environment in the Canary Islands. A laser-scattering Nova Fitness SDS011 sensor was operated continuously for approximately three and a half years, which is longer than most other studies using this type of sensor. The impact of African dust outbreaks on the aerosol concentrations was assessed, showing a significant increase in both PM10 and PM2.5 concentrations during the outbreaks. Additionally, a good correlation was found with a nearby reference instrument of the air quality network of the Canary Islands' government. The correlation between the PM10 and PM2.5 concentrations, the effect of relative humidity, and the stability of the sensor were also investigated. This study highlights the potential of this kind of sensor for long-term air quality monitoring with a view to developing extensive and dense low-cost air quality networks that are complementary to official air quality networks. [ABSTRACT FROM AUTHOR]

The literature on water use in hotels has identified numerous determinants of water consumption, but a consensus has yet to be reached on the influence of some of these factors. This article aims to enhance the current research framework on water use in the hotel sector by presenting a case study of one hotel in Tenerife, Canary Islands. The conceptual framework of water consumption in hotels is presented based on the previous literature. Starting from that, basic statistical analysis and bivariate correlations were performed on water consumption data from 2007 to 2019 to determine the significant factors affecting both total water consumption and consumption per guest night. Special attention was paid to water usage in gardens and the impact of weather conditions, as there is a lack of research focused on them. Additionally, the water management actions of the hotel were classified according to the business' themes proposed for the Sustainable Development Goals, using an internationally recognized guide, thus addressing one of the gaps identified in the literature. The results generally support previous research findings, but some discrepancies were noted regarding the number of guest nights and the effectiveness of implementing water-saving measures. This raises new questions about the characteristics of various water-saving measures, such as room renovation, and their influence on customer behavior, which may alter the intended impact on water consumption. Therefore, the findings of this study can provide an insight into unclear aspects in this area. They could also benefit hotels in terms of sustainability communication by allowing them to position their actions with an internationally recognized framework. [ABSTRACT FROM AUTHOR]

Despite that previous research exists, there is a need for further research on the quantitative aspects of this Nexus. Existing Water-Energy-Environment Nexus management tools and frameworks are based on indicators aiming to model the whole system, analyze the involved resources, and test potential management strategies. The environmental, social, and economic consequences of actions already taken and ongoing projects require important focus because of the strong relationship between water and energy supply, and that both are key issues for society's development and sustainability. The present research focuses on the indicators that the Water-Energy-Environment Nexus tools and frameworks use to analyze the whole problem. Existing tools often require large amounts of data, becoming a time-consuming process that lowers the capacity to evaluate the political problems of high pollutants. With the aim of accelerating time evaluation, this research builds an indicator to rapidly evaluate the Water-Energy-Environment Nexus implications of replacing fossil-based power generation systems with wind and photovoltaic renewable energy systems in the water-scarce region of the Canary Islands. This indicator allowed the rapid evaluation of storylines in a small system with well-defined boundaries. Results show that the water sustainability index improved by 6.2% in comparison to fossil-based plants, while reducing 2750 tons of CO2. Although this methodology can be easily applied in different scenarios and locations, it further development to evaluate system boundaries and to provide extensive results. [ABSTRACT FROM AUTHOR]

The occurrence of carbonatites in oceanic settings is very rare if compared with their continental counterpart, having been reported only in Cape Verde and Canary Islands. This paper provides an overview of the main geochemical characteristics of oceanic carbonatites, around which many debates still exist regarding their petrogenesis. We present new data on trace elements in minerals and whole-rock, together with the first noble gases isotopic study (He, Ne, Ar) in apatite, calcite, and clinopyroxene from Fuerteventura carbonatites (Canary Islands). Trace elements show a similar trend as Cape Verde carbonatites, almost tracing the same patterns on multi-element and REE abundance diagrams. 3He/4He isotopic ratios of Fuerteventura carbonatites reflect a shallow (sub-continental lithospheric mantle, SCLM) He signature in their petrogenesis, and they clearly differ from Cape Verde carbonatites, i.e., fluids from a deep and low degassed mantle with a primitive plume-derived He signature are involved in their petrogenesis. [ABSTRACT FROM AUTHOR]

Climate change and the appearance of pests and pathogens are leading to the disappearance of palm groves of Phoenix canariensis in the Canary Islands. Traditional pathology diagnostic techniques are resource-demanding and poorly reproducible, and it is necessary to develop new monitoring methodologies. This study presents a tool to identify individuals infected by Serenomyces phoenicis and Phoenicococcus marlatti using UAV-derived multispectral images and machine learning. In the first step, image segmentation and classification techniques allowed us to calculate a relative prevalence of affected leaves at an individual scale for each palm tree, so that we could finally use this information with labelled in situ data to build a probabilistic classification model to detect infected specimens. Both the pixel classification performance and the model's fitness were evaluated using different metrics such as omission and commission errors, accuracy, precision, recall, and F1-score. It is worth noting the accuracy of more than 0.96 obtained for the pixel classification of the affected and healthy leaves, and the good detection ability of the probabilistic classification model, which reached an accuracy of 0.87 for infected palm trees. The proposed methodology is presented as an efficient tool for identifying infected palm specimens, using spectral information, reducing the need for fieldwork and facilitating phytosanitary treatment. [ABSTRACT FROM AUTHOR]

Climate change may shift species outside of their current climatic tolerances, which can be problematic for oceanic islands with limited options for species migration. Their alpine habitats, which represent islands within islands, are a special concern due to high endemism rates. The Canary Islands have two examples for such fragile ecosystems above 2000 m, on La Palma and Tenerife. This study contributes an assessment of the Canary Islands' climatic habitat for 47 alpine plant species under observed climate change (1959–1989 versus 1990–2019 periods) as well as for future projections (2041–2060 and 2061–2080 periods). We analyzed the contraction of climatic habitats and migration requirements (biotic velocity) for each species to compensate for observed and predicted climate change. Our results suggest that temporary climate refugia exist on Tenerife but are insufficient on La Palma, where habitat loss due to historical climate change has already created an area of significant concern: the Cumbre Vieja Natural Park. On Tenerife, current alpine species can find suitable climate habitats in the caldera area and on the Teide-Pico Viejo volcano. That said, migration paths toward these refugia are long and complex, and human-assisted migration may be required. Species-specific statistics to support such management interventions are provided in this study. [ABSTRACT FROM AUTHOR]

A survey of the lichen family Graphidaceae in Macaronesia (Madeira, the Canary Islands, and the Azores) is presented, with detailed treatments for the genera Allographa, Fissurina, and Graphis. All other species are listed and new records provided. A key to all Graphicacy known from Macaronesia, except the thelotremoid species, is presented. The following species are newly described: Fissurina azorica, Fissurina elaiocarpoides, Fissurina nigrolabiata, and Topeliopsis juniperina. Many species are newly recorded for one or more islands of the three archipelagos. [ABSTRACT FROM AUTHOR]

Simple Summary: The rat lungworm, Angiostrongylus cantonensis, is the world's leading cause of eosinophilic meningitis in humans. It is an emerging zoonotic parasite endemic to Asia and the Pacific Islands that has spread to all continents except Antarctica. In the Canary Islands, its presence was first detected in 2010 on the island of Tenerife. Numerous studies demonstrated the high capacity of A. cantonensis to colonize new areas, especially its ability to parasitize a wide range of animals. Due to the similarity of the ecosystems that we can find between the islands that make up the Canary Archipelago and the great diversity of species of both vertebrates and terrestrial gastropods, the objective of this study was to analyze several species as possible hosts of A. cantonensis on other islands in the Canary Islands, with the use of molecular tools. The present study confirmed the presence of A. cantonensis in two mammalian species, Mus musculus and Felis catus, and in four terrestrial gastropod species, Limacus flavus, Milax gagates, Insulivitrina emmersoni, and Insulivitrina oromii. The presence of A. cantonensis implies a possible risk to humans and other animals, which justifies the need for control measures to control the possible risk of infection and, thus, prevent public health and veterinary problems. Angiostrongylus cantonensis is a metastrongyloid nematode and the etiologic agent of angiostrongyliasis, a disease characterized by eosinophilic meningitis. This emerging zoonotic parasite has undergone great expansion, including in some regions of Europe and America. In the Canary Islands, the parasite was first discovered parasitizing Rattus rattus on the island of Tenerife in 2010. To date, the distribution of this parasite in the Canary Islands has been restricted to the northern zone and the main cities of Tenerife. Using molecular tools for the sentinel species present in the Canary Islands, this study confirmed the presence of the nematode on two other islands in the Canary Archipelago: La Gomera and Gran Canaria. Furthermore, this emerging parasite was detected, besides in the common definitive host R. rattus, in wild Mus musculus and Felis catus and in four terrestrial gastropod species, Limacus flavus, Milax gagates, Insulivitrina emmersoni, and Insulivitrina oromii, two of them endemic to La Gomera, for the first time, increasing the number of non-definitive host species. This study reinforces the expansion character of A. cantonensis and highlights the importance of knowledge about sentinel species for identifying new transmission locations that help prevent and control the transmission of the parasite and, thus, prevent public health problems. [ABSTRACT FROM AUTHOR]

Simple Summary: The cave fauna of the Macaronesian archipelagos is rich in endemic species. In this region, most studies have been carried out in the Azores and the Canary Islands. In contrast to these archipelagos, the arthropod fauna of the lava tubes of the Madeira has not been well studied. Madeira is the only island in this archipelago with lava tube complexes suitable for endogenous arthropod species. In the two known complexes, San Vicente and Machico (Cavalum), 13 endemic species have been recorded; among these, there are two critically endangered cave spiders of the genus Centromerus. These caves not only have no protection measures, and while they are not exploited for tourism, they are under serious threats by the frequent passage of people. The San Vicente complex, the largest on the island, has undergone profound structural modifications for its tourist exploitation but still, since its inauguration in 1996, receives thousands of visitors per year. Until now, faunal studies of Madeiran caves have been the result of casual collecting. This work is the first monitoring study of Madeira's cave fauna. One-year monitoring has been done in four lava tubes of Machico: the Cavalum lava tubes (I, II, III) and the Landeiros tube. This study aimed to make a species checklist of the cave fauna present. So far, only three species of Collembola have been described for the Madeira lava tubes. Here we describe four new species, Neelus serratus Jordana & Baquero sp. nov., Coecobrya decemsetosa Jordana & Baquero sp. nov., Coecobrya octoseta Jordana & Baquero sp. nov., and Sinella duodecimoculata Jordana & Baquero sp. nov., and we update the checklist of the Collembola of lava tubes from three to 16 species. At present, the Machico complex caves represent the island's only natural lava tube habitats and are probably the main contributor to Madeira's cave biodiversity. The cave fauna of the Macaronesian archipelagos is rich in endemic species. Unlike the Azores and the Canary Islands, the cave fauna of the Madeira archipelago is little known. The only two cave complexes studied, Machico and São Vicente, lack protection measures. São Vicente is seriously threatened because it is being exploited for touristic purposes, while the Machico complex, the only one in its natural state, is open to the public but without any control. The importance of the conservation of this cave fauna is indisputable. So far, of the 13 cavernicolous species recorded, two of them—genus Centromerus—are critically endangered. Apart from occasional sampling, no monitoring study has ever been carried out. The aim of this work has been to make a species checklist of the cave fauna of the Machico complex, the least studied so far. For this purpose, during 2001–2002, a monitoring study was carried out using traps and manual collections in the lava tubes of Landeiros and Cavalum (I, II, III). Fourteen species of springtails were recorded. Of these, four are new species, Neelus serratus Jordana & Baquero sp. nov., Coecobrya decemsetosa Jordana & Baquero sp. nov., Coecobrya octoseta Jordana & Baquero sp. nov., and Sinella duodecimoculata Jordana & Baquero sp. nov., and one is a new record for the archipelago, Lepidocyrtus curvicollis Bourlet, 1839. [ABSTRACT FROM AUTHOR]