56 research outputs found
<i>Sinelobus stanfordi</i> (Richardson, 1901): A new crustacean invader in Europe
This short note reports on the first European records of Sinelobus stanfordi (Crustacea: Tanaidacea: Tanaidae). The species has been recorded from five different water bodies in the Dutch coastal area and in the docks of the Belgian harbour of Antwerp. S. stanfordi was until now not known to inhabit (North-) European coasts and estuaries. It is thus very likely that its origin is non-indigenous
Tweekleppigen (Bivalvia) in de Zeeschelde: verkennende monitoring en potentiële rol van schelpdieren in de Boven-Zeeschelde
New crustacean invaders in the Schelde estuary (Belgium)
This paper reports on the first records of three non-indigenous crustacean species in the Zeeschelde estuary (Belgium). All three species are native to the Western Pacific Ocean and are probably transported in ballast water or hull fouling. The isopod Synidotea laevidorsalis has been recorded earlier in Europe from two locations, in the south of France and in Spain. The present records constitute a range extension of more than 1000 kilometres to the north. The crab Hemigrapsus takanoi and the prawn Palaemon macrodactylus were found for the first time in the brackish reaches of the Schelde estuary. The finding of these species demonstrates the vulnerability of the estuarine system to the invasion of exotic species
10 jaar monitoring op het Groot Buitenschoor
The results of 10 years monitoring on the Groot Buitenschoor are reported. Macrobenthos data were analysed to explore both temporal and spatial trends in biomass and density, related to some abiotic parameters (sediment composition, altitude). Micro-pollution of the sediment was examined for several years. Evolutions in tidal marsh vegetation were assessed by comparison of two vegetation maps. Changes in wintering and migrating waterbird communities were analysed and related to environmental characteristics and macrobenthos populations. Finally an attempt was made to identify possible impacts of the construction and exploitation of the nearby container terminal
Overzicht analyseresultaten van de sedimentkarakteristieken langs de Zeeschelde en haar zijrivieren (1999 tot september 2005)
Pace: An Advanced Structure for Handling Multitechnique NDT Data
The analysis of NDT data is a problem of growing importance and complexity, encountered in many industrial fields, such as electricity production, oil industry, aeronautics, infrastructure inspection or metal production. This is why dedicated systems have begun to appear in the previous years to handle this particular part of a nondestructive inspection, located after the data acquisition and leading to the diagnosis
Tidal wetland restoration at Ketenisse polder (Schelde Estuary, Belgium): developments in the first year
Ketenisse polder is a former intertidal brackish marsh (30ha) situated in the mesohaline part of the Schelde Estuary. In the 19th century its central part was embanked as a polder. In the mid 1980’s the area was raised above intertidal level when it was used as a dumping site for the excavated soil from the Liefkenshoek tunnel. In 2002 the area was restored, it was levelled with a weak slope below mean high water level, creating the optimal starting conditions for the development of intertidal mudflats and marshes. Geomorphological changes, sediment characteristics and colonisation by phytobenthos, vegetation, zoobenthos, water birds and breeding birds at the restored site are monitored. The monitoring results of the first year after tidal restoration are presented. Sedimentation as well as erosion between 0 and 30cm was observed in the first year. Local changes in stream current patterns caused erosion on parts of the former mudflats; sheltered depressions filled up relatively fast. Median grain size showed large variation. Organic carbon content of the sediment varied between 0.5 and 15% and was closely related to sediment medium grain size. Chlorophyll a concentrations were negatively correlated with median grain size and tended to increase from the low water line to the shore. They were comparable to nearby intertidal areas and displayed similar seasonal variability with a maximum in spring. The large surface covered wtithVaucheria was indicator of initiated succession towards tidal marsh. Scirpus maritimus and transitional vegetations to Chenopodiaceae-vegetations established with increasing altitude. The Chenopodiaceae-vegetations were relicts of earlier vegetations before the tidal restoration, and will probably disappear. The macrobenthos community was dominated by Oligochaetes, which were present in 73% of all samples and attained an average density of about 40*103 ind. m-2. Other macrobenthos species found were nematods, copepods and Corophium. On the sheltered sampling stations macrobenthic densities were high compared to those on nearby intertidal areas. In the first season, 15 breeding bird species were recorded, the most common species being the Pied Avocet (Recurvirostra avosetta). The most common waterbirds were Common Shelduck (Tadorna tadorna), Greylag Goose (Anser anser), Pied Avocet (Recurvirostra avoset) and Lapwing (Vanellus vanellus), typical species for the mesohaline part of the estuary. The first year’s results suggest that Ketenisse polder has the potential to develop towards a varied and normal functional intertidal area
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