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Costly battles to prevent flooding and combat pollution should enlist a
natural and often unrecognised ally – trees and woodland
Trees have long been known to soak up carbon dioxide, but their parallel
abilities to reduce pollution and prevent flooding are sharply defined
in a new report from the Woodland Trust
The benefits of trees
and woods
Conserving and restoring native woods, and creating new ones, can
improve water quality, reduce localised flooding, and may alleviate the
effects of larger floods.
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Creating native woodland in the right place can reduce pollution
entering water courses by as much as 90% and has the potential to
mitigate large and small floods
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Restoring conifer plantations to native woodland or other habitats
can reduce acidification of water and increase water quantity.
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Maintaining the existing area of native woodland will help to preserve high
water quality and continue to have a role in reducing floods
How land use
affects water
Rivers, streams, ditches and groundwater are all affected by land use
around them. This could be nutrients draining out of agricultural fields
and polluting ditches or chemicals washed off roads and soaking down
into the groundwater
This means how land is managed and what grows on it has a big impact on
how polluted water is and how much water there is.
How trees and woods interact with
water
Trees affect water quality and quantity in the following ways:
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Trees take up large amounts of water through their roots and ‘catch’
rainfall with their leaves, branches and trunks. This can affect
water the amount of water in river.
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Trees stabilise soil with their roots, so increasing the amount
soaking into the soil and reducing the amount of water running off
the surface. This helps reduce soil erosion, washing of sediment
into water, and the effects of flooding.
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Woodland, in the
right place, can slow down flood waters as the trees and shrubs are
a barrier to the flow of water as compared to shorter vegetation or
bare ground.
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They take up nutrients and pollutants from the soil. This reduces
the amount of pollutants entering rivers
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Their leaves ‘scavenge’ or catch pollutants from the air which are
later washed off into watercourses by rain. This can lead to
pollution and acidification of water
particularly by
conifers.
Press release
Woods are hidden ally in flooding and pollution fight
Links
Woodland actions for biodiversity and their role in water management
(PDF 2.9MB - opens in a new window)
Image gallery - High resolution images for press use.
Forest Research - The Research Agency of the Forestry Commission .
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Woodland actions for biodiversity
and their role in water management
(PDF 2.9MB - opens in a new window)
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