March 29, 2012
When people talk about the city, the first thing they thought is the building and the traffic. It’s hard to connect city to the ecological and the environment. But as the humanity is rapidly urbanizing, by 2010, more than 50% of the world population is expected to live in the city. (The World Bank, 2010) Cities can be tremendously efficient. It can easier to provide water and sanitation for a large number of people living closer together, while access to health, education, and other social and cultural services is also much more readily available. However, as a city grows, the cost of meeting people basic needs are increases, as does the strain on the environment and natural resources. That’s why urban ecosystem is so important to us.
The emerging field of urban ecology as both valid and central to understanding the global environment now embraced in the scientific community. According to the data given by the World Bank about the concentration of human activity in urban centers, the trues is humans are the dominant species in all ecosystems, and the pace of environmental change, urban ecology is a critical area for environmental research. “Understanding urban natural resources and urban natural systems also has important implications for public health, economic development, education and community development in urban areas.” (Charles P. 2001)
If we thinking about the city, the development of ecological will have a broad and profound impact on all the important issues of social which faced by urban stakeholders. For example, public health, resource allocation, water quality, energy conservation, historical and natural preservation will all benefit from a revisionist approach that includes the biology of the system as the foundation for its understanding and management.
Urban ecosystem and current problem
The definitions of “urban” are varying among countries and often are specific to the political, social, and economic context in which they are utilized. “There also are another explain about urban which defined by The United States Census Bureau which is the populated regions with a density of 1600 people/km^2 or greater and a minimum population of 2500.” (Alan R. 2003)
Human demography has shown a steady increase in the percentage of people living in cities. “Beginning with the advent of agriculture 5,000-10,000 years ago, humans have been developing bigger and more densely populated urban centers. This pattern of urbanization is evident in both developed and developing nations.”(Bolund P. 1999) As the research did by the Millennium Ecosystems Assessment, “Urbanization and urban growth continue to be major demographic trends. The world’s urban population increased from about 200 million (_15% of world population) in 1900 to 2.9 billion (_50% of world population) in 2000, and the number of cities with populations in excess of 1 million increased from 17 in 1900 to 388 in 2000. As people are increasingly living in cities, and as cities act as both human ecosystem habitats and drivers of ecosystem change, it will become increasingly important to foster urban systems that contribute to human well-being and reduce ecosystem service burdens at all scales.” (Global & Multiscale Assessment Reports, 2001)
(Global & Multiscale Assessment Reports, 2001)
As human population has increased, so has our species’ impact on global ecosystems. “The fossil record points to five major periods of rapid extinction during the past 500 million years on the planet, all of which occurred prior to the evolution of our human lineage. These catastrophic events were triggered by rapid, un-buffered environmental change. The most recent complete cycle, triggered by an asteroid impact on the planet, occurred approximately 65 million years ago during the Cretaceous period and caused the extinction of at least 50% of all of the...