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As noted on the previous page, "ecosystems" are
described to include:
All the living organisms and
all the non-living components
of a given area
interacting as a
whole functional unit.
Urban Ecosystems
Thus, we need to consider the
wildlife, plant life, humans, and non-living natural components of inner
cities in our thinking about ecosystems. Urban Ecosystems
are/were natural ecosystems that have been altered, modified, or changed by humans in a variety of ways and in varying
degrees.
Some cities and towns in more recent times have wisely planned and
left natural open space and greenbelt areas with trees and plant life among the
developed areas. These natural areas and parks have provided places
for wildlife to survive, preserved some beneficial ecological
processes, and enhanced the quality of life for
people living and working in these communities.
Ecosystems
without Eco
On the other hand, there are many areas (large and small) in urban ecosystems
that are almost entirely devoid of nature. Areas where
little or no thought was given to preserving some natural
aspects and ecological processes in the landscape.
What about the
wildlife, the people, and the environmental health in such
places? Where do the children go to play, and to learn
about nature? Where do the wild things go? How far
will humans and wildlife have to go to find nature, as urban
sprawl spreads forever out covering over the natural landscape?
Urban Heat
Islands
In many cities where explosive growth and development have
occurred without consideration of the environment,
urban heat islands have been created. This
happens when too much preexisting natural vegetation has been
replaced by dense concrete jungles, and too much heat
from sunlight is absorbed and retained by man-made materials.
This concentrated heat can be seen by remote sensors NASA has in
space. Some major culprits causing this phenomena involve
the concrete of building
surfaces; dark tar in rooftops; and asphalt paving in roads,
airports, parking lots, and driveways. These surfaces collect and absorb more heat from the sun rather than
reflect it. Street canyons of clustered tall
skyscrapers with narrow streets between them are another
problem, in that the normal cooling air flow of winds are
blocked from circulating. All these things in urbanizing a
natural environment disrupt the ecological processes of thermal
balance, and heat islands develop. As a city heats up,
more air conditioning is used. This requires more energy
to be generated by power plants, leading to more toxic
emissions. During hot summer months, heat islands often
can increase the amount of smog created by vehicles.
People that live and work in heat islands are at more risk
regarding their health.
Regenerative
Ecosystems
We need to redesign Heat Islands into Eco-Cities
as regenerative ecosystems that function to
support the natural environment rather than deplete and pollute
it. Use of materials such as reflective roofing and
lighter colored paving will help mitigate some of the harmful
effects of development. Another important way to lessen
the impact of development is to increase urban forest cover in
cities. Free shade tree programs are being offered in some
cities. The Sacramento Municipal Utility District (SMUD),
in collaboration with the Sacramento Tree Foundation, has
planted more than 350,000 SMUD trees to help the environment and
improve air quality in the region.
In the past, we
didn't realize the harmful effects human activities would have
until the damage was already done. But, we no longer can
use that as an excuse for the predicament our environment is in.
Ignorance is not bliss, as the old saying goes; it's remiss.
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