Thanks-Minor extraction on land: sand, gravel and clay

The map shows the geological recoverable amount of sand, gravel and clay when no more than 5 meters of coating has to be excavated. Surface minerals are used for the production of many building materials. In the Netherlands, around 150 million tonnes of building materials are needed each year. Part of it comes from abroad, part is obtained by reuse (15 to 20 %), but a large part is still obtained from primary extraction. Since 1900, the extraction of high sand has been carried out at various locations by reducing ground level in the context of agricultural improvements (exchange plotting). Since the 1970s, there has been a decline in superficial dissipation due to increasing social resistance and stricter legislation. Sand extraction is now mainly carried out in concentrated wells. In addition, extraction takes place through the ‘work making’ principle. For example, in new construction projects sand is extracted for use in the project and at the same time creates water storage. The extraction of surface minerals requires around 400 hectares of land per year. About half of this, about 200 hectares, remains as deep water. The other 200 hectares will be given a new spatial destination through refurbishment, for example as a nature or recreation area. Alternative is the extraction of sand from the IJsselmeer, the Randmeren and the North Sea. The extraction of gravel is mainly foreseen from the mesh works in Limburg. The extraction and reservation of sand and gravel are regulated by law and land based win locations are designated by the province. The extraction of sand and gravel creates a space shed that can conflict with other uses on the one hand, on the other hand, extraction can also go hand in hand with design issues such as the provision of space for the rivers and temporary water storage.本地图展示了开挖覆盖层不超过5米时，砂石与黏土的地质可采储量（geological recoverable amount）。 地表矿产（surface minerals）可用于生产各类建筑材料。荷兰每年约需1.5亿吨建筑材料，其中部分源自进口，15%至20%通过再生利用获取，但仍有大部分依赖原生开采（primary extraction）。 自1900年起，为推进农业改良（地块互换，exchange plotting），荷兰在多处通过降低地面标高开展高品位砂石开采作业。 自20世纪70年代起，受社会阻力不断增加、立法监管日趋严格影响，表层砂石开采规模持续下滑。当前砂石开采主要集中于规模化矿区；此外，开采作业遵循“工程联动”原则：例如在新建工程项目中，开采的砂石可直接用于工程建设，同时同步打造蓄水空间。 地表矿产开采每年约占用400公顷土地，其中约一半（即200公顷）将留存为深水水域，剩余200公顷将通过修复改造赋予新的空间用途，例如打造自然保护区或休闲游乐区。除此之外，砂石开采也可在艾瑟尔湖（IJsselmeer）、兰德湖（Randmeren）及北海海域开展；砾石开采则主要规划于林堡省（Limburg）的网状矿区。 砂石的开采与储备受法律监管，陆上开采点位由各省划定。砂石开采会带来区域空间格局的变化，一方面可能与其他土地利用方式产生冲突，另一方面也可与相关规划设计协同推进，例如为河道治理预留空间、建设临时蓄水设施。