Evidence type: Research
Organisation: Woodland Trust
The Woodland Trust believes that climate change is the biggest threat to the UK's native woodland. This booklet summarises for those actively engaged in climate change and environmental policy the complex interdependencies between forests and climate and why our view of forests and woods must change. It describes the adaptive measures we believe are necessary for woodland in the UK to remain resilient in the face of climate change and to offer a higher quality, more sustainable environment for everyone.
Forests are of crucial importance in the global carbon cycle, both as sources and sinks for atmospheric CO2.
In the northern hemisphere and particularly in temperate areas, increases in CO2 may enable forests to grow faster because of increased photosynthesis, leading to additional uptake of carbon by forests. But hopes that climate change could mean increased forest productivity may be misplaced since an increase in temperature also increases respiration by plants and can speed breakdown of soil organic matter, both of which release CO2 to the atmosphere.
Trees sequester carbon from the atmosphere using roots as well as leaves and needles. Undisturbed forest soils also accumulate organic matter that in turn stores carbon. Creating new forests as carbon sinks, as a method of mitigating climate change, is consequently a potentially attractive option.
However, for the UK to become carbon neutral, through forestry planting alone, would require an area of 50 million hectares. This is twice the land area of the UK.
We cannot think of individual woods or nature reserves without consideration of the wider landscape. We must promote opportunities for movement and adaptation of species within the landscape, and create new landscapes that make this possible.
By working with nature, adaptation strategies attempt to reduce the frequency and intensity of these events, for instance, by planting woodland and re-creating grassland. In a country like Britain with such low woodland cover,it is ironic and almost negligent, that there is not more research underway to investigate the potentially positive impacts that afforestation of water catchments and floodplain woodland would have in relieving flood risk and benefiting both wildlife and society.
The following steps must form part of an adaptation strategy:
- Preventing any further loss of semi-natural habitats,
- Restoring all woodland and other semi-natural habitats, which have been planted with non-native conifer plantations
- Targeting habitat creation in areas where there is the greatest potential for woodland biodiversity to expand and survive
- Reducing the negative effects of intensive land use on semi-natural habitats by creating protective 'buffers'
- Reducing the intensity of the land-use between semi-natural habitats, increasing the ability of wildlife to move through the landscape
- Continuing to regenerate woodland or create new woodland with 'native' or naturalised species.