![]() ![]() Due to the high demand for sand, rivers and beaches are being dug up, with major consequences for ecosystems, flood protection, groundwater levels and the navigability of rivers.Despite a seeming abundance of sand, and its low cost relative to other mined commodities, rapidly escalating global demand has led to pressure on supplies, and salt-free river sand is particularly prized for use in construction work.Īsia’s development boom is a key global driver of global sand demand – with Singapore by far the biggest importer. Sand can be compared to fossil fuels: we extract more sand than nature can replenish. It is a raw material that is not easily extractable in every location and that we need in ever-increasing quantities. The extraction of sand is a global problem. The models will also include the effects of sand extraction on the composition of the sea bed, and on the animals that live in it. The models will simulate how sand extractions change the flow, the turbidity of the water and the growth of phytoplankton, the tiny algae that zooplankton feed on. "We will investigate how zooplankton, tiny animals that juvenile fish feed on, are affected by sand extractions, using laboratory experiments and models”. "Our colleagues at Wageningen Marine Research will investigate which underwater landscape is favourable for juvenile fish, and therefore for the fishing community," says Johan van der Molen, researcher at NIOZ. Fishermen are involved in the research because they know better than anyone which slopes produce the best catches. So that fishing for plaice and sole is not threatened. The research consortium will now study, for example, in what shape, in what direction, with what gradients and to what depths sand can best be extracted. This is alarming because the Dutch coast is also very important as a nursery ground for commercial flatfish species such as sole and plaice that live on sandy North Sea bottoms. A great deal of fine sediment was later trapped in that area. Take the sand extraction site for the Second Maasvlakte, for example. "Because we need more and more sand, we need to think carefully about how we plan to leave the North Sea floor," says Martin Baptist, coordinator at Wageningen Marine Research. Thinking about how to leave the North Sea floor behind And locally the sea currents change because of the pits and gullies created on the bottom. “Sand extraction can cloud the water so much that it has a negative effect on the growth of algae, the basis of the marine food chain, and its main grazers, the zooplankton.” Habitat of animals also changes because the grain size of the remaining sand is different. Shells, worms, starfish and fish are sucked up and die,” says Dick van Oevelen, marine biologist at NIOZ. “Sand extraction causes damage to life in and on the sea bed. Not only because we want to build more roads, houses and residential areas, but also because the rising sea level means that we need more and more sand for coastal safety.Įffects of sand extraction in the North Sea But our need for sand is going to increase even more. Every year, we dredge a stretch of seabed the size of the island of Schiermonnikoog by some eighty centimetres. Every year, we extract around 12 to 15 million cubic metres to protect our coastline, plus around 15 million cubic metres sand for roads, residential areas and for concrete. ![]() In the Netherlands, we extract a lot of sand, especially from the North Sea. ![]()
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