Geography Reference
In-Depth Information
waters, reducing the costs in sewage systems. In addition, since trees act as noise
barriers, their use along roads can reduce one of the other unwelcome aspects of
urban life. Green spaces also help the absorption of rain water into the soil, whereas
the asphalt or concrete cover of so many city surfaces adds to the rapidity of runoff,
which in heavy storms can lead to excessive flooding. So cities with higher surface
permeability due to more green areas are more likely to cope with floods, as a series
of interactive maps in a recent report dealing with climate change and urban adap-
tation has also shown (EEA
2012
). Urban areas are also well-known heat islands,
since the roads and buildings absorb and keep heat, ensuring that they have higher
temperatures than rural areas. This led the European Environment Agency's (EEA
2011b
) climate modelling group to estimate the effect of green space in reducing
temperatures and improving health. They calculated that a 10 % increase in green
space in urban areas reduced average temperatures in European urban areas by 1 ﾰC,
whereas a 10 % decrease can lead to an 8.2 % increase in average temperature. In
a world in which global warming is known to be increasing, adding green space
reduces the negative effect of these heat island effects in summer. These effects are
not trivial, for in the summer of 2003 over 70,000 extra deaths were recorded in 12
European countries due to a heat wave.
Although these five sets of advantages provide the main positive benefits for
adding green space and parks in cities, they have been complemented by the rec-
ognition that green areas in cities can also provide
environmental restoration
, and
also help add to the
food supplies
of cities, issues that will be discussed in subse-
quent sections. As always with urban changes, the addition of green areas has many
problems, even negatives. For example, there is always the problem of reconciling
conflicting, or even incompatible, uses in these areas. More generally, the costs of
implementation and the maintenance of parks in particular may be an important line
item in urban municipality budgets, especially in areas where increasing vandal-
ism has destroyed plants and other property, leading to extra costs—although at-
tempts to involve schools in educating youths about respect for property and green
spaces has helped reduce some vandalism problems. The increase in urban budget
problems since the financial crisis from 2007 has led some towns to reduce main-
tenance, which decreases their attractiveness. Others have charged entrance fees to
some parks, in addition to the more usual payment for various recreational facilities,
which reduces their public accessibility. But a more periodic difficulty is associated
with the night-time problems of parks or forested areas in cities, a long standing
problem. Many become places where anti-social activities or criminal behaviour
occur after dark, making them dangerous, or at least unpleasant places, for the ma-
jority of the population who avoid such areas at night, though some with alterna-
tive life-styles may be attracted to them and accept the dangers. Although regular
park patrols cut out some of these problems for the majority, the usual response of
municipal authorities is to lock the parks at night and to discourage night usage—
which again restricts their potential use—except in areas which can have easily pa-
trolled and well-lit access routes or which contain functions such as entertainment
and food services that attract people.
