Search publications of the members of the Royal Belgian institute of natural Sciences
-
Ostracodes
-
Late Eifelian and Early Givetian ostracod assemblages from Wellin, Hotton and On-Jemelle (Ardenne, Dinant Synclinorium, Belgium). Paleoenvironmental implications
-
Middle/Late Givetian ostracod assemblages from the Aisne quarry (Durbuy area, Ardenne, Belgium). Biostratigraphic and palaeoecological implications
-
Repositioning Data Management Near Data Acquisition
- This chapter intends to propose a solution to the progressive paradigmatic drift that emerges when data is part of a workflow where processes and contexts are not accessible. In this case end users can have difficulties in identifying possible anomalies, or events that might be very important for the dataset and its interpretation. Since sustainable development is based on cross-disciplinary studies, this can revert in misunderstanding and difficulties to work collaboratively. To address this issue it is proposed to fill the gap between the data and its acquisition through a logging system named EARS that records underway data such as for example: meteo or swell, and events such as: anomalies or acquisition milestones. Once all these information are stored, they can be linked to the data through an OGC compliant metadata model and gathered as summaries as required by several data management initiatives.
-
Consistent patterns of spatial variability between NE Atlantic and Mediterranean rocky shores
- Examining how variability in population abundance and distribution is allotted among different spatial scales can inform of processes that are likely to generate that variability. Results of studies dealing with scale issues in marine benthic communities suggest that variability is concentrated at small spatial scales (from tens of centimetres to few metres) and that spatial patterns of variation are consistent across ecosystems characterized by contrasting physical and biotic conditions, but this has not been formally tested. Here we quantified the variability in the distribution of intertidal rocky shore communities at a range of spatial scales, from tens of centimetres to thousands of kilometres, both in the NE Atlantic and the Mediterranean, and tested whether the observed patterns differed between the two basins. We focused on canopy-forming macroalgae and associated understorey assemblages in the low intertidal, and on the distribution of Patella limpets at mid intertidal levels. Our results highlight that patterns of spatial variation, at each scale investigated, were consistent between the Atlantic and the Mediterranean, suggesting that similar ecological processes operate in these regions. In contrast with former studies, variability in canopy cover, species richness and limpet abundance was equally distributed among spatial scales, possibly reflecting the fingerprint of multiple processes. Variability in community structure of low intertidal assemblages, instead, peaked at the largest scale, suggesting that oceanographic processes and climatic gradients may be important. We conclude that formal comparisons of variability across scales nested in contrasting systems are needed, before any generalization on patterns and processes can be made.
-
Geographic patterns of biodiversity in European coastal marine benthos
- Within the COST action EMBOS (European Marine Biodiversity Observatory System) the degree and variation of the diversity and densities of soft-bottom communities from the lower intertidal or the shallow subtidal was measured at 28 marine sites along the European coastline (Baltic, Atlantic, Mediterranean) using jointly agreed and harmonized protocols, tools and indicators. The hypothesis tested was that the diversity for all taxonomic groups would decrease with increasing latitude. The EMBOS system delivered accurate and comparable data on the diversity and densities of the soft sediment macrozoobenthic community over a large-scale gradient along the European coastline. In contrast to general biogeographic theory, species diversity showed no linear relationship with latitude, yet a bell-shaped relation was found. The diversity and densities of benthos were mostly positively correlated with environmental factors such as temperature, salinity, mud and organic matter content in sediment, or wave height, and related with location characteristics such as system type (lagoons, estuaries, open coast) or stratum (intertidal, subtidal). For some relationships, a maximum (e.g. temperature from 15–20°C; mud content of sediment around 40\%) or bimodal curve (e.g. salinity) was found. In lagoons the densities were twice higher than in other locations, and at open coasts the diversity was much lower than in other locations. We conclude that latitudinal trends and regional differences in diversity and densities are strongly influenced by, i.e. merely the result of, particular sets and ranges of environmental factors and location characteristics specific to certain areas, such as the Baltic, with typical salinity clines (favouring insects) and the Mediterranean, with higher temperatures (favouring crustaceans). Therefore, eventual trends with latitude are primarily indirect and so can be overcome by local variation of environmental factors.
-
Essence of the patterns of cover and richness of intertidal hard bottom communities: a pan-European study
- Coastal ecosystems are highly complex and driven by multiple environmental factors. To date we lack scientific evidence for the relative contribution of natural and anthropogenic drivers for the majority of marine habitats in order to adequately assess the role of different stressors across the European seas. Such relationship can be investigated by analysing the correlation between environmental variables and biotic patterns in multivariate space and taking into account non-linearities. Within the framework of the EMBOS (European Marine Biodiversity Observatory System) programme, hard bottom intertidal communities were sampled in a standardized way across European seas. Links between key natural and anthropogenic drivers and hard bottom communities were analysed using Boosted Regression Trees modelling. The study identified strong interregional variability and showed that patterns of hard bottom macroalgal and invertebrate communities were primarily a function of tidal regime, nutrient loading and water temperature (anomalies). The strength and shape of functional form relationships varied widely however among types of organisms (understorey algae composing mostly filamentous species, canopy-forming algae or sessile invertebrates) and aggregated community variables (cover or richness). Tidal regime significantly modulated the effect of nutrient load on the cover and richness of understorey algae and sessile invertebrates. In contrast, hydroclimate was more important for canopy algae and temperature anomalies and hydroclimate separately or interactively contributed to the observed patterns. The analyses also suggested that climate-induced shifts in weather patterns may result in the loss of algal richness and thereby in the loss of functional diversity in European hard bottom intertidal areas.
-
Coexistence dilemmas in European marine spatial planning practices. The case of marine renewables and marine protected areas
- The question whether coexistence of marine renewable energy (MRE) projects and marine protected areas (MPAs) is a common spatial policy in Europe and how a number of factors can affect it, has been addressed by empirical research undertaken in eleven European marine areas. Policy drivers and objectives that are assumed to affect coexistence, such as the fulfillment of conservation objectives and the prioritization of other competing marine uses, were scored by experts and predictions were crosschecked with state practice. While in most areas MRE-MPA coexistence is not prohibited by law, practice indicates resistance towards it. Furthermore expert judgment demonstrated that a number of additional factors, such as the lack of suitable space for MRE projects and the uncertainty about the extent of damage by MRE to the MPA, might influence the intentions of the two major parties involved (i.e. the MRE developer and the MPA authority) to pursue or avoid coexistence. Based on these findings, the interactions of these two players are further interpreted, their policy implications are discussed, while the need towards efficient, fair and acceptable MRE-MPA coexistence is highlighted.
-
The role of physical variables in biodiversity patterns of intertidal macroalgae along European coasts
- In the frame of the COST ACTION ‘EMBOS’ (Development and implementation of a pan-European Marine Biodiversity Observatory System), coverage of intertidal macroalgae was estimated at a range of marine stations along the European coastline (Subarctic, Baltic, Atlantic, Mediterranean). Based on these data, we tested whether patterns in macroalgal diversity and distribution along European intertidal rocky shores could be explained by a set of meteo-oceanographic variables. The variables considered were salinity, sea surface temperature, photosynthetically active radiation, significant wave height and tidal range and were compiled from three different sources: remote sensing, reanalysis technique and in situ measurement. These variables were parameterized to represent average conditions (mean values), variability (standard deviation) and extreme events (minimum and maximum values). The results obtained in this study contribute to reinforce the EMBOS network approach and highlight the necessity of considering meteo-oceanographic variables in long-term assessments. The broad spatial distribution of pilot sites has allowed identification of latitudinal and longitudinal gradients manifested through species composition, diversity and dominance structure of intertidal macroalgae. These patterns follow a latitudinal gradient mainly explained by sea surface temperature, but also by photosynthetically active radiation, salinity and tidal range. Additionally, a longitudinal gradient was also detected and could be linked to wave height.
-
Assessment of the conservation value of the Vlakte van de Raan Site of Community Interest. MARECO report 16/02.
-
Amniotic eggshells from the Haţeg Basin (Upper Cretaceous, Romania).
-
Vertebrate remains in the 2003 Bernissart drill: histological assessment.
-
First Maastrichtian vertebrate assemblage from Provence (Vitrolles-La-Plaine, France).
-
Integrated results of the new material from the 2002-2003 boreholes in Bernissart (Mons Basin, Belgium).
-
Recent studies on the latest Cretaceous dinosaurs in Heilongjiang (Amur) River area.
-
Seafloor morphology and habitats of tidal channels in the Venice Lagoon, Italy tidal channel habitats. Chapter 9.
-
Limitations of Predicting Substrate Classes on a Sedimentary Complex but Morphologically Simple Seabed
-
Ergasilid copepods in Africa: first application of next-generation sequencing and update on distribution and phylogenetic position of Ergasilus kandti, a parasite of cichlid fishes
- Ergasilidae are a family of globally distributed copepods parasitizing freshwater fishes. Despite their widespread occurrence, their phylogeographic patterns are poorly understood, specifically in the African Great Lakes. Here, we aim to provide an update on distribution of Ergasilus kandti, a copepod species infecting Tylochromis polylepis, an endemic cichlid fish species in Lake Tanganyika, and the phylogenetic relationship of African ergasilids. We present the first record of E. kandti parasitizing the gills of T. polylepis in Lake Tanganyika proper, identified through light microscopy and, for the first time for any ergasilid, confocal laser scanning microscopy. We suggest that this technique adds spatial context to characters and are hardly visible while using light microscopy. Phylogenetic analyses based on ribosomal DNA fragments suggest two monophyletic groups of African ergasilids. However, the phylogenetic relationships of Ergasilus remain unresolved, possibly because of the insufficient resolution of these widely used phylogenetic markers and low taxonomic coverage. A comparison of ergasilid mitochondrial genomes highlights traits found in other parasite lineages including genome shrinkage and low evolutionary rates of the cox1 gene. This study presents the most extensive molecular characterization of any ergasilid species to date.
-
Recent non-marine ostracods (Crustacea) from New Caledonia (Melanesia, Pacific Ocean)
- The New Caledonian Archipelago is a hot spot for biodiversity and endemism. Here, we report on new records of nine species from localities on the main island, Grande Terre, and illustrate these: Ilyodromus viridulus (Brady, 1886), Stenocypris hislopi Ferguson, 1969, S. macedonica Petkovski & Meisch, 1996¸ S. malayica Victor & Fernando, 1981, Bradleytriebella lineata (Victor & Fernando, 1981), Hemicypris pyxidata (Moniez, 1892), Heterocypris incongruens (Ramdohr, 1808), Cypridopis vidua (O.F. Müller, 1776) and Limnocythere stationis Vávra, 1891. We also provide redescriptions and illustrations of the valves and carapace of Stenocypris marginata Daday, 1910 sensu Méhes, 1939, Cypris granulata Daday, 1898 and Kennethia major (Méhes, 1939); for the latter species also including some soft parts. Therefore, twenty two certain species have thus far been reported from the New Caledonian Archipelago. The status of seven uncertain species is also discussed. Previous records of Stenocypris major (Baird, 1859) from Grande Terre, mainly by Méhes, are here considered to belong to S. hislopi. We propose to reject the presence of Cyprinotus cingalensis Brady, 1886 in New Caledonia and suggest to consider Cypridopsis sarasini Méhes, 1939 as an “uncertain species” (sensu Meisch et al. 2019). We also argue that Eucypris wolffhuegeli Méhes, 1914 might be a synonym of H. incongruens and suggest that Strandesia rouxi Méhes, 1939 might be considered a junior synonym of an existing species, pending further research.
-
High water temperature significantly influences swimming performance of New Zealand migratory species
- Anthropogenic structures in freshwater systems pose a significant threat by fragmenting habitats. Effective fish passage solutions must consider how environmental changes introduce variability into swimming performance. As temperature is considered the most important external factor influencing fish physiology, it is especially important to consider its effects on fish swimming performance. Even minor alterations in water properties, such as temperature and velocity, can profoundly affect fish metabolic demands, foraging behaviours, fitness and, consequently, swimming performance and passage success. In this study, we investigated the impact of varying water temperatures on the critical swimming speeds of four migratory New Zealand species. Our findings revealed a significant reduction in critical swimming speeds at higher water temperatures (26°C) compared to lower ones (8 and 15°C) for three out of four species (Galaxias maculatus, Galaxias brevipinnis and Gobiomorphus cotidianus). In contrast, Galaxias fasciatus exhibited no significant temperature-related changes in swimming performance, suggesting species-specific responses to temperature. The cold temperature treatment did not impact swimming performance for any of the studied species. As high water temperatures significantly reduce fish swimming performance, it is important to ensure that fish passage solutions are designed to accommodate a range of temperature changes, including spatial and temporal changes, ranging from diel to decadal fluctuations. Our research underscores the importance of incorporating temperature effects into fish passage models for habitat restoration, connectivity initiatives, and freshwater fish conservation. The influence of temperature on fish swimming performance can alter migration patterns and population dynamics, highlighting the need for adaptive conservation strategies. To ensure the resilience of freshwater ecosystems it is important to account for the impact of temperature on fish swimming performance, particularly in the context of a changing climate.
