According to most environmental scientists and policy makers, woodland expansion could be one of the most effective strategies to combat climate change. However, a new study led by the University of Plymouth which analyzed the temperate rainforests in Dartmoor, England, has found that protecting and expanding woodland is far from simple, and depends upon a variety of factors.
“The planting of trees and an end to deforestation are increasingly being highlighted as low cost and environmentally sensitive mechanisms to combat climate change. These measures have been factored into the net-zero agendas of UK and other governments, with world leaders also pledging to address the issue during COP26 in Glasgow last year,” said study lead author Dr. Thomas Murphy, a research fellow in Environmental Sciences at the University of Plymouth.
“Our findings however suggest the expansion of oak woodland into UK upland pasture systems is not a simple process. They may have a critical role to play, but these important temperate rainforests have been historically degraded and are now highly fragmented. Reversing that trend is likely to require strategic planting and informed livestock management.”
“Getting this right, however, will warrant a delicate balancing act and close cooperation with a range of stakeholders, including particularly landowners and graziers, at a time when upland farms are facing severe financial pressures and there are ongoing changes in incentives.”
According to Dr. Murphy and his colleagues, natural expansion is insufficient to adequately aid carbon storage, flood mitigation, and biodiversity protection in such forests. Instead, strategically targeted interventions and selective planting of certain vegetation types would be more appropriate strategies to improve forest quality.
The researchers argue that livestock grazing should be encouraged in areas close to native oak trees at the edge of woodlands since they can help reduce dense and competitive vegetation. However, in areas rich in oak seedlings and saplings, livestock should be excluded for at least 12 years to increase sapling survival and growth.
In addition, the scientists suggest that strategic planting and grazing management schemes should be implemented on upland valley slopes where current ecosystem provision is low and soil hydrological recovery is necessary. Finally, older and larger oak samplings (four to seven years) could be planted directly in regions where dense vegetation protects saplings from livestock.
The study is published in the journal Ecological Solutions and Evidence.