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Assessing the accessibility to critical resources for volcanic risk management in Goma, DR Congo
No full textImages dans le vitrail domestique d’une fameuse héroïne de Boccace : la dévouée et aimante Griselda
Get PDFFirst record of <i>Nigma puella</i> (Simon, 1870) in Belgium, validated by genetic identification (Araneae, Dictynidae)
Get PDFThe presence of the bleeding heart spider Nigma puella (Simon, 1870), a member of the Dictynidae family, had not been formally confirmed in Belgium until now. The species was recorded in Tihange in 2023 through a photograph posted on Observations.be / Waarmeningen.be, the Belgium participatory platform for monitoring biodiversity. Subsequently, in 2024, two males and a female were captured at the same site. Their identity is now confirmed through sequencing a fragment of their cytochrome c oxidase I (COI) gene and examining their morphological characteristics. A list of key characters is also presented for the three species of Nigma Lehtinen, 1967 found in Belgium. The list of Dictynid species occurring in Belgium is updated
Development of a multi-entry identification key for economically important fruit fly larvae (Diptera: Tephritidae: Dacinae).
No full textAnalysis of the long-range transport of the volcanic plume from the 2021 Tajogaite/Cumbre Vieja eruption to Europe using TROPOMI and ground-based measurements
Get PDFThe eruptions of the Tajogaite volcano on the western flank of the Cumbre Vieja ridge on the island of La Palma between September and December 2021 released large amounts of ash and SO2. Transport and dispersion of the volcanic emissions were monitored by ground-based stations and satellite instruments alike. In particular, the spectrometric fluorescence and Raman lidar for atmospheric moisture sensing (RAMSES) at the Lindenberg Meteorological Observatory measured the plume of the strongest Tajogaite eruption of 22–23 September 2021 over northeastern Germany 4 d later. This study provides an analysis of SO2 vertical column density (VCD) and layer height (LH) measurements of the volcanic plume obtained with Sentinel-5 Precursor/TROPOspheric Monitoring Instrument (TROPOMI), which are compared to the observations at several stations across the Canary Islands. Furthermore, a new modeling approach based on TROPOMI SO2 VCD measurements and the Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT) was developed, which confirmed the link between Tajogaite eruptions and Lindenberg measurements. Modeled mean emission height at the volcanic vent is in excellent agreement with co-located TROPOMI SO2 LH and local lidar ash-height measurements. Finally, a comprehensive discussion of the RAMSES measurements is presented. A new retrieval approach has been developed to estimate the microphysical properties of the volcanic aerosol. For the first time, an optical particle model is utilized that assumes an irregular, non-spheroidal shape of the aerosol particles. According to the analysis, the volcanic aerosol consisted solely of fine-mode inorganic, solid, and irregularly shaped particles – the presence of large aerosol particles or wildfire aerosols could be excluded. The particles likely had an isometric to slightly plate-like shape with an effective half of the particle maximum dimension around 0.1 µm and a refractive index of about 1.51. Moreover, mass column values between 70 and 110 mg m−2, mean mass concentrations of 45–70 µg m−3, and mean mass conversion factors between 0.21 and 0.33 g m−2 at 355 nm were retrieved. Possibly RAMSES observed, at least in part, volcanic secondary sulfate aerosol, which was produced by gas-phase homogeneous reactions during the transport of the air masses from La Palma to Lindenberg
An Eye in the Sky - Tracking Ammonia Pollution From Space
Get PDFAmmonia is a chemical commonly found in fertilizers, cleaning products, and even animal waste. While this substance does have some important uses, rising emissions of ammonia in the atmosphere can pose serious risks to human health, plant and animal health, and the environment. Therefore, measuring and tracking ammonia levels in the air is crucial, especially as human activities, such as large-scale farming and industrial processes, release more and more ammonia. In this article, we will tell you about the main sources of ammonia pollution, the dangers it poses to health and the environment, and how scientists are using satellites to monitor ammonia levels from space. By keeping a close eye on ammonia trends, researchers hope to trigger ways to reduce emissions and protect the planet for future generations
Description of a new endemic <i>Enteromius</i> (Teleostei: Cyprinidae) from the upper Malagarazi in Burundi: Lessons for a protected area under implementation
No full textRecent collecting efforts in the upper Malagarazi basin (2013 2022) allowed for an integrative study based on qualitative (colour), quantitative (meristic and metric), and barcoding gene [mtDNA, cytochrome c oxidase (COI)] data of specimens similar to Enteromius sp. ascutelatus , being a previously identified, potentially, new species. Based on these data, the present study confirms its identification as a new species for science, which is here formally described as Enteromius nzigidaherai sp. nov. This new species belongs to the group of Enteromius species for which the last unbranched ray of the dorsal fin is flexible and devoid of serrations along its posterior edge. This species has a horizontal series of black spots at the midlateral level of the sides. Three congeneric species, known from the Congo basin sensu lato, with two of them also found in the upper Malagarazi basin, are most similar to it. However, E. nzigidaherai sp. nov. is distinguished from the two sympatric upper Malagarazi species, that is, E. quadrilineatus and E. lineomaculatus, at least by two meristics and two morphometrics. It is also distinguished from E. urostigma, known from the upper Congo basin, by two meristics and one, apparently related, morphometric. In addition, a barcoding (mtDNA, COI) study revealed that the specimens of E. nzigidaherai sp. nov. form a well-supported, separate lineage, with a K2P genetic distance of more than 10% with specimens identified as E. quadrilineatus and E. lineomaculatus, both originating from the upper Malagarazi basin and for which tissue samples were available. Finally, the new species was found to be endemic to the upper reaches of two left bank affluents of the upper Malagarazi basin: the Muyovozi and the Kinwa. However, both affluents are threatened by human activities, which seem to have resulted in its local disappearance as recent intensive collecting efforts in the latter affluent have remained unsuccessful. The species should thus be considered Critically Endangered (CR) according to IUCN criteria B1ab(ii,iv)c(i,iii). Therefore, it is hoped that the present description draws renewed attention to the importance of aquatic protection in the region by highlighting the need for the effective establishment of the Malagarazi Nature Reserve and concern for its optimal delimitation to efficiently protect the entire ichthyofauna of the upper Malagarazi, without excluding the fish species confined to its affluent rivers
