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The economic importance of the Belgian ports: Flemish maritime ports, Liège port complex and the port of Brussels – Report 2016
Get PDFThis Working Paper analyses the economic importance of the Belgian ports based largely on the annual accounts data for the year 2016. As the years prior to 2016 have been described in earlier papers in the same series, we mainly focus on the figures for 2016 and developments between 2015 and 2016. On the back of strong growth, direct value added in the Belgian ports remained more or less stable in 2016 at around € 18 000 million (current prices) or roughly 4.3% of Belgium’s GDP. Direct value added declined in the Flemish seaports, mainly in the port of Antwerp. Ghent and Zeebrugge could only partly compensate for the fall in Antwerp’s value added, while Ostend showed a small decline itself. The inland ports as a whole grew over the period 2015-2016; the port of Brussels registered a decline and the Liège port complex an increase. Indirect value added is around 82% of the direct figure. After declining from 2012, direct employment in the Belgian ports was more or less stable in 2016 at around 115 000 FTE or approximately 2.8% of Belgium’s total domestic employment. Direct employment in the Flemish seaports increased, mainly in the ports of Zeebrugge, Ghent and Antwerp. Ostend showed a decline in employment. The inland ports recorded lower employment; the port of Brussels registered a decline, as did the Liège port complex. Indirect employment is around 1.2 times the direct figure. Delving deeper into the data and trying to explain the above trends in terms of the structural composition of the Belgian ports shows that all ports are concentrated on a few sectors, and within those sectors often on just a handful of companies. Based on the figures of the traffic, the Flemish ports can be considered as real bridgeheads for trade with the UK. Developments regarding the modalities and consequences of the Brexit therefor should be followed with the greatest attention. Given the existing import and export volumes in terms of tonnage, it seems it will mostly be a challenge in Zeebrugge and to some extent for Antwerp
Herziening van de initiële beoordeling voor de Belgische mariene wateren. Kaderrichtlijn Mariene Strategie – Art 8, lid 1a & 1b
Get PDFControl of the repeatability of high frequency multibeam echosounder backscatter by using natural reference areas
Get PDFThe increased use of backscatter measurements in time series for environmental monitoring necessitates the comparability of individual results. With the current lack of pre-calibrated multibeam echosounder systems for absolute backscatter measurement, a pragmatic solution is the use of natural reference areas for ensuring regular assessment of the backscatter measurement repeatability. This method mainly relies on the assumption of a sufficiently stable reference area regarding its backscatter signature. The aptitude of a natural area to provide a stable and uniform backscatter response must be carefully considered and demonstrated by a sufficiently long time-series of measurements. Furthermore, this approach requires a strict control of the acquisition and processing parameters. If all these conditions are met, stability check and relative calibration of a system are possible by comparison with the averaged backscatter values for the area. Based on a common multibeam echosounder and sampling campaign completed by available bathymetric and backscatter time series, the suitability as a backscatter reference area of three different candidates was evaluated. Two among them, Carr, Renard and Kwinte, prove to be excellent choices, while the third one, Western Solent, lacks sufficient data over time, but remains a valuable candidate. The case studies and the available backscatter data on these areas prove the applicability of this method. The expansion of the number of commonly used reference areas and the growth of the number of multibeam echosounder controlled thereon could greatly contribute to the further development of quantitative applications based on multibeam echosounder backscatter measurements
Status of the undisturbed mangroves at Brunei Bay, East Malaysia: a preliminary assessment based on remote sensing and ground-truth observations
Get PDFBrunei Bay, which receives freshwater discharge from four major rivers, namely Limbang, Sundar, Weston and Menumbok, hosts a luxuriant mangrove cover in East Malaysia. However, this relatively undisturbed mangrove forest has been less scientifically explored, especially in terms of vegetation structure, ecosystem services and functioning, and land-use/cover changes. In the present study, mangrove areal extent together with species composition and distribution at the four notified estuaries was evaluated through remote sensing (Advanced Land Observation Satellite—ALOS) and ground-truth (Point-Centred Quarter Method—PCQM) observations. As of 2010, the total mangrove cover was found to be ca. 35,183.74 ha, of which Weston and Menumbok occupied more than two-folds (58%), followed by Sundar (27%) and Limbang (15%). The medium resolution ALOS data were efficient for mapping dominant mangrove species such as Nypa fruticans, Rhizophora apiculata, Sonneratia caseolaris, S. alba and Xylocarpus granatum in the vicinity (accuracy: 80%). The PCQM estimates found a higher basal area at Limbang and Menumbok—suggestive of more mature vegetation, compared to Sundar and Weston. Mangrove stand structural complexity (derived from the complexity index) was also high in the order of Limbang > Menumbok > Sundar > Weston and supporting the perspective of less/undisturbed vegetation at two former locations. Both remote sensing and ground-truth observations have complementarily represented the distribution of Sonneratia spp. as pioneer vegetation at shallow river mouths, N. fruticans in the areas of strong freshwater discharge, R. apiculata in the areas of strong neritic incursion and X. granatum at interior/elevated grounds. The results from this study would be able to serve as strong baseline data for future mangrove investigations at Brunei Bay, including for monitoring and management purposes locally at present
Functional trait responses to sediment deposition reduce macrofauna-mediated ecosystem functioning in an estuarine mudflat
Get PDFHuman activities, among which dredging and land use change in river basins, are altering estuarine ecosystems. These activities may result in changes in sedimentary processes, affecting biodiversity of sediment macrofauna. As macrofauna controls sediment chemistry and fluxes of energy and matter between water column and sediment, changes in the structure of macrobenthic communities could affect the functioning of an entire ecosystem. We assessed the impact of sediment deposition on intertidal macrobenthic communities and on rates of an important ecosystem function, i.e. sediment community oxygen consumption (SCOC). An experiment was performed with undisturbed sediment samples from the Scheldt river estuary (SW Netherlands). The samples were subjected to four sedimentation regimes: one control and three with a deposited sediment layer of 1, 2 or 5 cm. Oxygen consumption was measured during incubation at ambient temperature. Luminophores applied at the surface, and a seawater–bromide mixture, served as tracers for bioturbation and bio-irrigation, respectively. After incubation, the macrofauna was extracted, identified, and counted and then classified into functional groups based on motility and sediment reworking capacity. Total macrofaunal densities dropped already under the thinnest deposits. The most affected fauna were surficial and low-motility animals, occurring at high densities in the control. Their mortality resulted in a drop in SCOC, which decreased steadily with increasing deposit thickness, while bio-irrigation and bioturbation activity showed increases in the lower sediment deposition regimes but decreases in the more extreme treatments. The initial increased activity likely counteracted the effects of the drop in low-motility, surficial fauna densities, resulting in a steady rather than sudden fall in oxygen consumption. We conclude that the functional identity in terms of motility and sediment reworking can be crucial in our understanding of the regulation of ecosystem functioning and the impact of habitat alterations such as sediment deposition