Urban Green Areas – their functions under a changing lifestyle of ...

surround. That is most intensive for the air temperature in parks on hot summer-days,
with some wind and low humidity.
UGAs help buffer the level of groundwater. A bare surface cannot retain rainwater
and buffer and the level of groundwater as well as a surface covered with vegetation.
Those are important points when urbanisation rates are high. Planners and designers
were careless about sewage system, there were terrible flood in rain seasons which is
responsible partly by city planners. And lakes and ponds in parks and gardens can
keep and supply water as well. Thus, UGAs are taken for granted as supply water
sources for groundwater (see JIM 2008).
Regarding parks and gardens influent almost all environmental indexes positively. On
the one hand, they raise humidity and oxygen content in the air of surrounding areas.
On the other hand, they absorb noise and dust from nearby transportation systems or
industry. FETZER (1995: 142) shows that coniferous trees catch 80 %, while
deciduous trees catch 60 % dust particles. By that, UGAs make more liveable for
their flora system and reduce green house effects to its own urban.
UGAs keep biodiversity. UGAs as nature sites are habitats for fauna and flora.
Obviously, so many species lives in natural environment, but not concrete surfaces.
Therefore, if everywhere in urban settlement is houses, factories, buildings, streets,
we loose so many ecological systems. That means existing genres are popular
phenomenal. Biologists determined that it ruins the Earth (TARRAMT/CORDELL
2002).
At last but not least, there is a study indicated that “the noise reduction effect green
barriers. The results show that a shelterbelt with a width of 10 meter only decreases
noise by 3-6 dB. A reduction of 20 dB is first achieved at a width of 50 meter”
(LAGSTROEM 2004: 30). The specific ecological function of a green area depends
of probably on its site, size and kinds of vegetation, etc. (see
BOLUND/HUNHAMMAR 1999).
2.4.2 Economic benefits
Overall the economic benefits of urban green spaces were somewhat neglected in focus
group discussions of the benefits that they might bring to urban areas (see
MARCOTULLIO 2001; TZOULAS et al. 2007). Only one group of young people in
Sheffield, mentioned the possible benefits for green spaces in attracting businesses to the
city and two groups mentioned the role they might play in attracting visitors and tourists.
Less is known about economic benefits of urban green spaces, compared with the intention
of increasing the attractiveness of the areas and enhancing surrounding land values.
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