The TWIRLS project came to a close in September 2007. We'd like to thank all those involved in the project, especially our funders and collaborators. We've recently updated this site to provide easy access to the results of our activities.
The Treating Wastes for Restoring Land Sustainability (TWIRLS) was a project conerned with improving, restoring or remediating degraded land in Europe, using locally sourced waste materials. These materials can be mixed
together for the sustainable production of a growing medium, enabling plants to become established and
a whole ecosystem to develop.
The project was funded by the European Commission LIFE-Environment programme between October
2004 and September 2007, and managed in the College of Natural Sciences at Bangor University,Wales.
Partner organisations and collaborators in the project were: the quarrying companies Alfred
McAlpine Slate (in Wales) and Titan Cement (in Greece), the paper manufacturer UPM Kymmene UK
(in Wales), the Soil Science Institute of Athens, the Association of Communities and Municipalities of
the Attica Region (ACMAR), the waste-management company Envar (in England), and the Welsh
This work is important for three reasons. There is now a pressing need to:
- reduce the volume of waste disposed of by landfill. Europe produces approximately 2000 million
tonnes of waste per year – a figure that is increasing by around 10 per cent each year. Stricter
European legislative targets are reducing the amount of waste that can be sent to landfill, and we
have an environmental responsibility to recycle more of our waste.
- protect and improve soil. More than 16 per cent of the EU’s total land area is considered to have
degraded soil, in terms of erosion, water infiltration or carbon sequestration, or its fertility or
- reduce greenhouse gas emissions. Significant reductions in the EU’s emissions are required
following the commitments generated by the Kyoto Protocol and the 2007 climate summit in Bali.
Improved waste management can make a cost-effective contribution to meeting these targets.
Adding organic matter to soil improves its quality and functionality. The process has long been recognised
as beneficial to the soil’s fertility, structure, water retention and buffering capacity (the ability to resist rapid
changes in pH). Organic matter has large pore spaces, which improve water, gas and nutrient flows, and
its particles have a large, highly charged surface area, which can adsorb, or ‘attract’, nutrients and trace
elements, helping to prevent them leaching away and improving their availability to plants. Organic matter
is particularly beneficial to microorganisms as it supplies energy for growth as well as providing a longterm
supply of nutrients such as nitrogen, phosphorus and sulphur.
Soil degradation can occur for a number of reasons, including: contamination by pollutants from industry
or agriculture; intensive agriculture (especially the production of cereals); disturbance, such as mining or
quarrying; and industrial development, which seals the soil with an impermeable surface layer.
The TWIRLS project worked with four sites suffering from a
range of soil degradation issues.
- The waste rock tips of a slate quarry in Blaenau Ffestiniog,
NorthWales, which had no soil or vegetation.
- An urban brownfield area in North Wales, the site of the
former Shotton Steelworks, which had some areas
contaminated with persistent organic pollutants, and other
sandy areas supporting little vegetation.
- A former coal mine,Woolley Colliery, where colliery shale
made the soil so acidic that it prevented revegetation.
- Kamariza schist quarry in Greece, part of the Parnitha National Park, where the ground had become
compacted and waterlogged and had no soil or vegetation.
Urban brownfield sites are potentially important
refuges for a variety of insects and a key concern of the TWIRLS project
is to establish whether the addition of composted organic wastes to brownfield
sites has a positive or negative effect on insect biodiversity. In addition
to calculating the abundance and diversity of ground dwelling beetles
at our urban brownfield site in Shotton, we have compiled a database consisting
of high quality digital photos of each species found.
We've been busy at our experimental sites
and you can read about our recent activities in our Site
science and industry for environmental gain