Vanden Eede, S.

Vincx, M.

Open Marine Archive

Can we protect our coastline and the beach ecosystem at the same 
time? 
Vanden Eede Sarah and Magda Vincx 
Research Group Marine Biology, Biology Department, Ghent University, Krijgslaan 281, S8,  
B-9000 Ghent, Belgium 
E-mail: sarahl.vandeneede@ugent.be; magda.vincx@ugent.be   
Whether we like it or not, the climate is changing. An increase in storms and rising sea levels are 
particularly problematic for low lying countries like Belgium. Every kilometer of our coastline is 
intensively used and densely populated. Coastal protection against erosion and flooding is as such 
absolutely indispensable. Soft coastal defence techniques like beach nourishment might help to 
solve the problem. The word ‘nourishment’ means supplying a beach with sand because its sand 
has either flown away with the wind or got washed off with the waves. As it safeguards the natural 
dynamics of the coast, beach nourishment has rapidly become a widely applied protective measure 
in Europe. Although beaches are often regarded as barren deserts, nothing can be further from the 
truth. Underneath the surface lies the world of the benthic organisms. The macrobenthos are the 
seafloor inhabiting benthic forms larger than one millimeter. They play a key role in the wider beach 
ecosystem, being part of the diet of intertidal birds and fish.  
 
Our research aims at unravelling the in-situ ecological effects of beach nourishment on the soft-
sediment macrobenthos. We focus on Lombardsijde beach as it was nourished from March until 
September 2009, under optimal conditions. It can be regarded as a prototype of ecological beach 
nourishment. Approximately 650,000m³ of sand was deposited on top of the beach over a distance 
of around 1,200m. The sand (grain size: 200-250μm) originated from the new fairway to Ostend. 
The soft substrates of Lombardsijde beach have been and are being extensively monitored since 
2004. Comparing the status of the beach before (t0 situation) and after (t1 situation) the 
nourishment provides us with the necessary answers. To distinguish the effects of beach 
nourishment from those of natural variation, we included control sites in our monitoring studies. 
The control site for Lombardsijde beach is the beach in front of Nieuwpoort-Bad.  
 
We discovered that Lombardsijde beach has changed between 2006 and 2010. Most changes took 
place during and directly following the nourishment with a clearly visible peak value for abundance 
(intertidal: 61species; subtidal: 162species), density (intertidal: 745247individuals.m-²; subtidal: 
131253597individuals.m-²) and biomass (intertidal: 0.70.1g.m-2; subtidal: 85.217.0g.m-2) during 
autumn 2010. Unlike previous years, we also found significant differences between the intertidal 
median grain size of Lombardsijde and its control site. The beach profile of Lombardsijde was 
altered in such a way that it resembles the beach profile of Nieuwpoort-Bad almost perfectly. No 
other distinct negative trends for the macrobenthos were found one year after ecological 
nourishment. 
 
 
 - 98 -


Can we protect our coastline and the beach ecosystem at the same time?

Can we protect our coastline and the  
beach ecosystem at the same time? 
 
Vanden Eede Sarah* & Vincx Magda 
 sarahl.vandeneede@ugent.be,  Marine Biology Section, Ghent University, Krijgslaan 281 - S8, 9000 Gent, Belgium  +329/264.85.15 
changing climate 
                        soft coastal defense techniques, like beach nourishment  
low lying countries, like Belgium 
2004 – 2011 (Spring): 
• Lombardsijde beach has changed, mostly during and 
directly following the nourishment  
• clearly visible peak value during autumn 2010 for: 
 
 
 
 
 
• no distinct negative trends for macrobenthos   
 
First results suggest: ‘ecological’ beach nourishment = 
good solution BUT further research is needed! 
 
Focus on Lombardsijde beach:  
• ±650000m³ sand over 1200m 
• Median grain size: 200-250µm  
• March-September 2009 
= ‘ecological’ beach nourishment 
 
? 
Intertidal Subtidal 
Density (# ind/m²) 745±247 13125±3597 
Abundance (# species/sample) 6±1 16±2 
Biomass (g AFDW/m²) 0.7±0.1 85.2±17.0 
What are the ecological in-situ impact effects of beach nourishment on macrobenthos? 
 
Before After Control Impact design: 
  t0  situation     ↔    t1 situation 
    2004, 2006 & 2008                      2010, 2011 & 2012 
 
• different years 
• different seasons (Spring/Autumn) 
 
0
100
200
300
400
500
600
700
800
900
2004 2006 2008 2009 -
Spring
2009 -
Autumn
2010 -
Spring
2010 -
Autumn
2011 -
Spring
2011 -
Autumn
Evolution of density and median grain size - Lombardsijde intertidal
Density (# ind/m²) Median grain size (µm)
nourishment


Can we protect our coastline and the beach ecosystem at the same time?

Abstract

Similar works

Full text

Available Versions

Open Marine Archive

Open Marine Archive