Subject and objectives
The Raw Materials Initiative highlights the improvement of the EU knowledge base as a condition to enhance sustainable supply from within the EU. Comprehensive information on geological resources is required and should underpin the preparation of spatial plans. Knowledge on the distribution, composition, and dynamics of geological resources is indeed critical in responding most appropriately to increasing societal and economical challenges. Such knowledge is the backbone of long-term strategies securing sustainable supplies of energy, water, and mineral resources.
During the last decade, socio-economical demands for marine geological resources have increased up to 100 million m³ in the North-East Atlantic region (OSPAR). In Belgian waters, only 2.5 million m³ has been extracted annually, though in a new vision on Marine Spatial Planning, many new initiatives are foreseen that require much larger volumes of sand and gravel and thus depend on the availability and sustainable supply of aggregate resources. At present, there is neither a quantitative estimate of the resources available, nor of their quality and depletion rates. No digital geological knowledge base exists, even though it is clearly a necessary platform for assessing the transnational impact of aggregate extraction.
Within the southern North Sea, the Belgian part of the North Sea (BPNS) is a relatively resource-depleted environment. The sandy and gravelly Quaternary deposits at the seabed are the main sediments of resource quality. They are typically thin, averaging less than 10 m. In between sandbanks their thickness is locally less than 2.5 m. For coastal protection and industry needs, exploitation of marine aggregates has been in place since the late 1970s. Since extraction has increased in volume and frequency, during the last decade, monitoring results have shown perturbations in the seabed, with limited regeneration of the sand volumes reflecting only minor import from elsewhere in the system. In the absence of regeneration, true resource sustainability cannot be achieved; therefore, new and conscientious approaches are needed on how to optimize the use of available resources, considering the surface and subsurface potential. A key research question in view of developing a sustainable geological marine exploitation strategy is: How can the exploitation be optimized in the long-term while limiting negative impacts on the ecosystem?
This project contributes to solving this research question and has the following main objectives:
These project objectives will be achieved following a flexible, integrated and innovative approach, anticipating on an urgent need for adaptive management in an era of rapid environmental change and fast-changing socio-economical boundary conditions. TILES results will have wide applicability in the integrated management of the marine environment and will contribute, through its anticipation on Europe’s Marine Strategy Framework Directive, to the EU’s commitments made at the 2002 World Summit on Sustainable Development.
Sustainable use of marine resources is inevitably linked to a good environmental status (GES). This is the 2020 goal of the Marine Strategy Framework Directive. To allow monitoring of the evolution towards GES, a series of descriptors have been defined. Related to physico-chemical seabed attributes, descriptor 6 on seafloor integrity and descriptor 7 on hydrographic conditions are relevant to TILES. MSFD Art. 9 stipulates that GES for seafloor integrity refers to the structure and functions of the ecosystems that need safeguarding, without adversely affecting benthic ecosystems, whilst GES for hydrographic conditions means that permanent alteration of hydrographical conditions does not adversely affect marine ecosystems. ‘Not adversely affected’ can be interpreted as meaning that impacts may be occurring, but all impacts are sustainable such that natural levels of diversity, productivity, and ecosystem processes are not degraded.