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Article Reference Dispersal capacity underlies scale-dependent changes in species richness patterns under human disturbance
Changes in the species richness of (meta-)communities emerge from changes in the relative species abundance distribution (SAD), the total density of individuals, and the amount of spatial aggregation of individuals from the same species. Yet, how human disturbance affects these underlying diversity components at different spatial scales and how this interacts with important species traits, like dispersal capacity, remain poorly understood. Using data of carabid beetle communities along a highly replicated urbanization gradient, we reveal that species richness in urban sites was reduced due to a decline in individual density as well as changes in the SAD at both small and large spatial scales. Changes in these components of species richness were linked to differential responses of groups of species that differ in dispersal capacity. The individual density effect on species richness was due to a drastic 90% reduction of low-dispersal individuals in more urban sites. Conversely, the decrease in species richness due to changes in the SAD at large (i.e., loss of species from the regional pool) and small (i.e., decreased evenness) spatial scales were driven by species with intermediate and high dispersal ability, respectively. These patterns coincide with the expected responses of these dispersal-type assemblages toward human disturbance, namely, (i) loss of low-dispersal species by local extinction processes, (ii) loss of higher-dispersal species from the regional species pool due to decreased habitat diversity, and (iii) dominance of a few highly dispersive species resulting in a decreased evenness. Our results demonstrate that dispersal capacity plays an essential role in determining scale-dependent changes in species richness patterns. Incorporating this information improves our mechanistic insight into how environmental change affects species diversity at different spatial scales, allowing us to better forecast how human disturbance will drive local and regional changes in biodiversity patterns.
Located in Library / RBINS Staff Publications 2023 OA
Article Reference Description d’une nouvelle espèce du sud du Vietnam appartenant au genre Sarmydus Pascoe, 1867 (7e contribution à l’étude du genre Sarmydus Pascoe, 1867) (Coleoptera, Cerambycidae, Prioninae)
Located in Library / RBINS Staff Publications 2022
Article Reference De witste ‘witsteen’ Gobertangesteen.
Located in Library / RBINS Staff Publications 2023
Article Reference QWIP: A Quantitative Metric for Quality Control of Aquatic Reflectance Spectral Shape Using the Apparent Visible Wavelength
The colors of the ocean and inland waters span clear blue to turbid brown, and the corresponding spectral shapes of the water-leaving signal are diverse depending on the various types and concentrations of phytoplankton, sediment, detritus and colored dissolved organic matter. Here we present a simple metric developed from a global dataset spanning blue, green and brown water types to assess the quality of a measured or derived aquatic spectrum. The Quality Water Index Polynomial (QWIP) is founded on the Apparent Visible Wavelength (AVW), a one-dimensional geophysical metric of color that is inherently correlated to spectral shape calculated as a weighted harmonic mean across visible wavelengths. The QWIP represents a polynomial relationship between the hyperspectral AVW and a Normalized Difference Index (NDI) using red and green wavelengths. The QWIP score represents the difference between a spectrum’s AVW and NDI and the QWIP polynomial. The approach is tested extensively with both raw and quality controlled field data to identify spectra that fall outside the general trends observed in aquatic optics. For example, QWIP scores less than or greater than 0.2 would fail an initial screening and be subject to additional quality control. Common outliers tend to have spectral features related to: 1) incorrect removal of surface reflected skylight or 2) optically shallow water. The approach was applied to hyperspectral imagery from the Hyperspectral Imager for the Coastal Ocean (HICO), as well as to multispectral imagery from the Visual Infrared Imaging Radiometer Suite (VIIRS) using sensor-specific extrapolations to approximate AVW. This simple approach can be rapidly implemented in ocean color processing chains to provide a level of uncertainty about a measured or retrieved spectrum and flag questionable or unusual spectra for further analysis.
Located in Library / RBINS Staff Publications 2022
Article Reference Assessment of PRISMA water reflectance using autonomous hyperspectral radiometry
Hyperspectral remote sensing reflectance (Rrs) derived from PRISMA in the visible and infrared range was evaluated for two inland and coastal water sites using above-water in situ reflectance measurements from autonomous hyper- and multispectral radiometer systems. We compared the Level 2D (L2D) surface reflectance, a standard product distributed by the Italian Space Agency (ASI), as well as outputs from ACOLITE/DSF, now adapted for processing of PRISMA imagery. Near-coincident Sentinel-3 OLCI (S3/OLCI) observations were also compared as it is a frequent data source for inland and coastal water remote sensing applications, with a strong calibration and validation record. In situ measurements from two optically diverse sites in Italy, equipped with fixed autonomous hyperspectral radiometer systems, were used: the REmote Sensing for Trasimeno lake Observatory (RESTO), positioned in a shallow and turbid lake in Central Italy, and the Acqua Alta Oceanographic Tower (AAOT), located 15 km offshore from the lagoon of Venice in the Adriatic Sea, which is characterised by clear to moderately turbid waters. 20 PRISMA images were available for the match-up analysis across both sites. Good performance of L2D was found for RESTO, with the lowest relative (Mean Absolute Percentage Difference, MAPD  25\%) and absolute errors (Bias  0.002) in the bands between 500 and 680 nm, with similar performance for ACOLITE. The lowest median and interquartile ranges of spectral angle (SA  8°) denoted a more similar shape to the RESTO in situ data, indicating pigment absorption retrievals should be possible. ACOLITE showed better statistical performance at AAOT compared to L2D, providing R2  0.5, Bias  0.0015 and MAPD  35\%, in the range between 470 and 580 nm, i.e. in the spectral range with highest reflectances. The addition of a SWIR based sun-glint correction to the default atmospheric correction implemented in ACOLITE further improved performance at AAOT, with lower uncertainties and closer spectral similarity to the in situ measurements, suggesting that ACOLITE with glint correction was able to best reproduce the spectral shape of in situ data at AAOT. We found good results for PRISMA Rrs retrieval in our study sites, and hence demonstrated the use of PRISMA for aquatic ecosystem mapping. Further studies are needed to analyse performance in other water bodies, over a wider range of optical properties.
Located in Library / RBINS Staff Publications 2022
Book Reference Het meest duurzame materiaal van België. Belgisch Porfier.
Located in Library / RBINS Staff Publications 2022
Inbook Reference Reuzen uit de Maas, een nieuw onderzoek van ijsschotszwerfstenen.
Located in Library / RBINS Staff Publications 2022
Article Reference Detection of Bonobos (Pan Paniscus) in Tropical Rainforest Canopies Using Drone-Based Thermal Imaging: A First Step Towards Accurately Estimating Population Sizes?
Surveying great ape populations is time-consuming and costly, and often relies on generalised parameters, resulting in imprecise population estimates. Using thermal imaging, through thermal cameras fitted on unmanned aerial vehicles, to detect primates directly from the air, may prove a useful alternative to conventional great ape population surveys. This may be especially true for bonobos (Pan paniscus) which, due to their large body size and nesting behaviour, could provide a uniquely identifiable thermal signature. We trialled the use of a thermal drone to record bonobos in their natural environment in the Democratic Republic of Congo, as a first step towards using the technique to survey great apes. Bonobos were observed asleep in their nests during all surveys at different flight speeds and heights, showing potential for the use of thermal drones as a method to survey great apes.
Located in Library / RBINS Staff Publications 2022
Techreport Reference Lithostratigraphic identification sheet Someren Member (Veldhoven Formation)
Located in Library / RBINS Staff Publications 2022
Inproceedings Reference Controls on rare earth element dynamics during low- and high-temperature fluid-rock interactions in carbonatites
Located in Library / RBINS Staff Publications 2023