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Planting Biomass Crops - assessment of options to reduce soil carbon loss - NF0441

The establishment of bio-energy crop plantations of short rotation coppice (Willow) trees may contribute to government strategy to mitigate net CO2 emissions in accordance with U.K. commitments to the U.N. Kyoto Protocol on Climate Change. In addition to the provision of "carbon neutral" fossil fuel replacement, bio-energy plantations may also contribute to CO2 emissions mitigation by enhancing sequestration of carbon in soil organic matter in the underlying soils.

We will review available literature and on-going research, both in the U.K. and internationally, on the potential for soil carbon sequestration under short rotation coppice (SRC) bio-energy crops. A particular concern is the effect of establishing SRC on grassland. Cultivation may stimulate initial losses of carbon offsetting the later benefits of sequestration of C into soil organic matter. Reducing soil tillage is likely to lower the initial losses of carbon from the disturbance of the organic matter. An experiment will be carried out on at Wellesbourne to test the effects of different cultivation treatments on the establishment and subsequent yields of short rotation coppice on a heavy soil. Conventional autumn ploughing will be compared against banded tillage methods, where only soil immediately in contact with the planting material is disturbed. The experiment will point to methods which promise to reduce initial soil disturbance, but it will be difficult to generalise the effects on CO2 emissions: Therefore, a review of algorithms will be made to asses the possibility of predicting the effects of these reduced tillage methods on overall C sequestration. To support this soil samples will be taken from established grassland of different ages, including Wellesbourne, to determine the relative effects of age of grassland on losses of CO2. This will enable the break-even point – when sequestration exceeds emissions – to be estimated for a range of sites. This information will be incorporated into a decision support tool to maximise the benefits of short rotation coppice crops established after grassland. Strategies of managing the changeover from grassland to short rotation coppice, while ensuring maximum C sequestration, will be a key output of the project.
Time-Scale and Cost
From: 2008

To: 2013

Cost: £329,772
Contractor / Funded Organisations
Warwick - HRI