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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]

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 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 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]