LIFE CO2SAND: Improving sandy substrates with clay
Climate change may make cover sand substrates more acidic and dehydrated, with the result that today's agricultural functions are no longer possible. The particpants within LIFE CO2SAND believe that they can make the substrates of arable land more resilient to climate change by adding clay to the sandy topsoil. The aim to treat 700 hectares of arable land with sandy substrates with clay, up to and including 2027, to increase the content of fine clay (lutite) to 8%.
The Province of Gelderland and Rijkswaterstaat are working closely together on the LIFE CO2SAND pilot project. Rijkswaterstaat aims to make its own large-scale earth-moving operations more sustainable, while the Province of Gelderland's focus is on making agriculture more sustainable.
Benefits of clay
Once it has been environmentally assessed, excavated clay soil is now frequently reused to make ponds and lakes less deep, or used in projects where the ground needs to be elevated. This means that the benefits of clay as an agricultural soil improver are not being exploited. The expected benefits for cover sand substrates treated with clay are listed below:
- The ground will retain greater volumes of water over a longer period
- Les nutrient run-off
- Greater agricultural yield
- Increase in nutrient availability for crops
- Increase in organic material in the soil, plus the expectation of more carbon being captured as a result
- Improvement in conditions for soil life
To add scientific credence to this, Wageningen University and Research and Eurofins are carrying out tests at de Marke experimental farm and various trial fields.
Encouraging municipalities with the soil-flow system dynamic model
The aim is to encourage high-quality reuse in new contracts for public projects. The Buyer Group is developing new procurement requirements for this. And LIFE CO2SAND is jointly working on the development of the soil-flow system dynamic model (SDMG). This model, developed by Copernicos, determines the circular value of excavated soil for a range of applications linked to municipal targets.
Policy makers, procurement teams and contractors can use the SDMG as a decision-making tool. The Environment and Planning Act offers options for upscaling this further. We want to offer support and encourage municipalities to configure soil-quality maps differently, and to make it possible to use soil from other regions.
Period
July 2021 - June 2027
European programme
LIFE
Project website
Partners
Rijkswaterstaat; Province of Gelderland; European Union; Wageningen University & Research; de Marke experimental farm