Orfeo BELSPO Instutional Open Access Repository for Federal Organisation
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Etat des connaissances archéologiques sur l’église Notre-Dame de Mousty à l’époque médiévale
No full textFirst record of three alien termite species (Insecta: Isoptera) in Belgium
No full textThe presence of subterranean termites (Family Rhinotermitidae) and drywood termites (Family Kalotermitidae) poses significant challenges as potential pests, capable of causing substantial damage to wooden structures and leading to economic losses. Some species within these families exhibit high levels of destructiveness and have become invasive in numerous regions worldwide. Introductions or expansions of termite populations often result from the importation of infested wood, plants, or soils. Here, we document the initial occurrences of three exotic termite species in Belgium: Cryptotermes brevis and Reticulitermes banyulensis in Brussels (Brussels Capital Region), and Reticulitermes flavipes in Brugelette (Hainaut province; Walloon region). Morphological identification of specimens was corroborated through DNA-barcoding validation. While infestations of Cryptotermes brevis and Reticulitermes banyulensis are likely inconsequential due to unfavorable local climatic conditions, the establishment and spread of Reticulitermes flavipes in Belgium is more likely and will be monitored closely. These findings underscore the importance of vigilance and effective pest management strategies to mitigate potential impacts
An ichthyological borderland: the fishfauna of Nyungwe National Park and surroundings (Rwanda, East Africa).
No full textA Statistical Study of Local Dust Storm Occurrences on Mars Using the 2.77 μm CO2 Band Observed by OMEGA/Mars Express
Full text linkLocal Dust Storms (LDS) are defined as dust storm phenomena that cover an area smaller than 1.6 × 106 km2 or persist for less than three sols. The study of LDS is critical for understanding dust transport processes in both horizontal and vertical directions and the evolution of large-scale dust storms on Mars. However, the relatively small scale and short lifetime make it difficult to detect with previous studies. OMEGA onboard Mars Express (MEx) has conducted spectroscopic measurements with high spatial resolution (up to ∼400 m/pixel). Here, we present a method to retrieve dust optical depth and detect LDS using the 2.77 μm CO2 absorption band. At this wavelength, photons are absorbed before reaching the surface, and the photons collected by OMEGA have been scattered around 20–30 km altitude by dust. We have detected 146 LDS events from the retrieved dust optical depth in MY27-29. The LDS were generally observed in the southern summer season, while frequent occurrences of LDS were observed during the northern summer (Ls = 130°–150°) in MY27. The remarkable increase in LDS is also identified just before the global dust storm in MY28. We found a peak in the probability of LDS around noon in both seasons, Ls = 0°–180° and Ls = 180°–360°. In Ls = 0°–180°, high probability areas are found only in specific regions, such as Chryse Planitia. The probability areas expands over a wide range, except high-latitude north of 40°N in Ls = 180°–360°. These findings highlight the spatiotemporal roles LDS play in dust transport, providing insights into the dust cycle (245/250 words)
Influence of temperature on crystallisation and dissolution of salts and salt mixtures in built environment
Full text linkSalt weathering significantly degrades building materials, necessitating a thorough understanding of
influencing factors. While prior research has focused on relative humidity (RH), temperature effects on
salt crystallisation and dissolution remain less explored. This study examines selected single salts and
mixtures, using the ECOS/RUSALT thermodynamic model to assess equilibrium behaviour across
temperatures from 1 °C to 50 °C and RH values from 15% to 98%. Results show that crystallisation
and dissolution RH generally decrease with rising temperature. Single salts exhibit monotonic
changes, whereas mixtures behave variably. Calcium-rich mixtures have lower mutual crystallisation
and dissolution RH than sulfate-rich ones, with further reductions in magnesium-containing mixtures.
Lower temperatures promote the formation of more output salts. Model limitations are acknowledged
to explain discrepancies between predictions and real-world observations. These findings enhance
understanding of salt behaviour under climatic variations, aiding strategies to mitigate salt damage in
building materials
République Démocratique du Congo, Carte administrative et routière de la ville de Goma - Quartier Mapendo
No full textInbreeding depression, functional traits and phenotypic plasticity in an endangered tree species with a mixed mating system
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Global Carbon Monoxide Column Derived from HIRAS-II/FY-3F Satellite Observations
Full text linkThe Hyperspectral Infrared Atmospheric Sounder-II (HIRAS-II) onboard China’s FungYun (FY)-3F meteorological satellite was launched in August 2023. This study presents the first attempt to retrieve the global carbon monoxide (CO) column from HIRAS-II/FY-3F spectra based on a newly established full-physics algorithm. The CO global columns derived from the HIRAS-II/FY-3F satellite are compared to measurements from the Infrared Atmospheric Sounding Interferometer (IASI) onboard Europe’s MetopB satellite, as both satellites have the same spectral range with a similar overpass time. The correlation coefficient between the IASI/Metop-B and HIRAS-II/FY-3F CO retrievals is about 0.8. The HIRAS-II/FY-3F satellite can capture well the regions with high CO values, e.g., Africa, North America, and East Asia. The relative difference in the CO global column between HIRAS-II and IASI is 1.2±13.7(1σ)%, which is within their combined retrieval uncertainty. The CO plumes from the fire emissions in North America between 18 and 23 July 2024 were observed by the HIRAS-II/FY-3F satellite and consistent with the CAMS (Copernicus Atmosphere Monitoring Service) model simulations. Our results show that the HIRAS-II/FY-3F spectra are of good enough quality to provide quantitative observations of global CO column remote sensing observations
