The right trees planted in the right places can reduce the risk of flooding, provide shade for our wildlife, reduce soil erosion and help to cool down our towns and cities.
Trees in the urban environment
The urban heat island effect means that temperatures in our towns and cities tend to be around 2°C higher than in rural areas. The built environment is also designed to increase runoff which means that water supply to these trees is often limited. Therefore it could be said that trees in urban areas are already adapted to the type of climate change that we can expect to see in the UK over coming decades. Trees and woodland are a vital component of what has become known as "Green Infrastructure" - a network of interconnected and multipurpose green areas. It is important to think about whether the species currently used as street trees will be suited to our future climate.
As well as reducing the risk of flooding in urban areas, woodland in headwater catchments can reduce the intensity and volume of floodwaters. Floodplain woodland lower in the catchment can provide floodwater storage and reduce peak flows.
Trees planted along riverbanks can also provide shade, helping to maintain lower water temperatures. This can help limit the effects of climate change on fish populations.
Soil erosion control
Tree canopies reduce rainfall intensity, act as a windbreak, and stabilise soil, reducing erosion. By reducing soil erosion trees also help to reduce consequent diffuse water pollution and the flooding that results from water courses silting up.