Trees
bring many benefits to humans in
the urban environment and some problems if they are not managed.
The
benefits include health improvement both psychological from their
presence and greenery to the filtering of air and water pollution.
London Planes and Limes are especially good at this as they have been
cultivated to cope with highly polluted atmospheres (in Victorian
times).
Trees also
provide shade and, if there are enough of them, reduce the heat wave
effect in a city. This is further improved by their cooling due to
evaporation, and evidence shows that a 10% increase in canopy cover
can
reduce a city’s peak temperature by some 3 degrees. This could save
lives. Trees mitigate the climate in the winter reducing heating bills
to a minor extent. They also provide a buffer to storm water run off
and
can delay or even minimise urban flooding if there are enough of them.
Bristol City Council aspires to a city wide canopy cover of 30% which is
very ambitious and will take decades. The canopy cover in our
conservation area is approx 15% and can only be increased to maybe 20%
by more garden trees and street and parks trees. The canopy cover in our
conservation area is approx 15% and can only be increased to maybe 20%
by more garden trees and street and parks trees.
What a leading expert had to say...
Please click here to read a summary of a talk given by Marcus Grant, to the Bristol Tree Forum. Marcus is the Deputy Director of the World Health Organisation Collaborating Centre based at UWE in Bristol
