To call a city a parasite is not to belittle it, but to be realistic.. In undisturbed nature, parasites and hosts tend to coevolve for coexistence; otherwise, if the parasite takes too m
Trang 1and the city provides many desirable cultural institutions, such
as museums and symphonies, that are not available in rural
areas
In summary, cities are essentially parasites on the
low-energy countryside To call a city a parasite is not to belittle it,
but to be realistic In undisturbed nature, parasites and hosts
tend to coevolve for coexistence; otherwise, if the parasite
takes too much from its host, both die if the parasite has
only one host Currently humans have only one habitable
hostFthe earth
Especially threatening to the global life-support ecosystems
is the explosive growth of mega-cities in the less-developed
nations, caused in part by the increasing dominance of
an-other techno-ecosystem, that of industrialized agriculture, with
its often excessive consumption of water and use of toxic and
enriching chemicals These systems produce more food
products per unit of space, but in turn are prodigious polluters
and by their economic might drive small farmers out of
business worldwide, forcing them into cities that are unable to
assimilate them This current situation illustrates what
engin-eer and former president of MIT PaulGray (1989)has written:
‘‘A paradox of our time is the mixed blessing of almost every
technological development.’’ In other words, technology has
its destructive as well as beneficial side To bring the natural
and technical ecosystems into a mutualist relationship will be
society’s greatest challenge in the twenty-first century
See also: Ecosystem Services Energy Flow and Ecosystems Human
Impacts on Ecosystems: An Overview
References
Force JE and Maddie GE (1997) The human ecosystem Society and Natural Resources 10: 369–382.
Gray PE (1989) The paradox of technological development In: Technology and the Environment, pp 192–205 Washington, DC: National Academy Press Lotka AJ (1925) Elements of Physical Biology Baltimore: Williams and Wilkins.
Machlis GE, Force JE, and Birch WR (1997) The human ecosystem as an
organizing concept in ecosystem management Society and Natural Resources
10: 347–367
Naveh Z (1982) Landscape ecology as an emerging branch of human ecosystem
science Adv Ecol Res 12: 189–237.
Odum HW (1936) Southern Regions of the United States Chapel Hill: University of
North Carolina Press
Odum HW and Moore HE (1938) American Regionalism New York: Henry Holt.
Sukachev VN (1959) The correlation between the concepts ‘‘forest ecosystem’’ and
‘‘forest biogeocoenose’’ and their importance for classification of forests IX International Botanical Congress 2: 387.
Tansley AG (1935) The use and abuse of vegetational concept terms Ecology 16:
284–307
Ecosystem, Concept of 63