Abstract 1. Urbanization and its influence on society, the city is the product of the development of social productive forces to a certain historical stage and the crystallization of human civilization. According to historical data and archaeological research, cities have existed for at least 5000 years. Since industrialization, the speed of urbanization has been accelerating. This concentration process is manifested in two forms: one is the increase in the number of cities, and the other is the continuous expansion of the population of each city. ......
Urbanization and its influence on society.
Cities are the product of the development of social productive forces to a certain historical stage and the crystallization of human civilization. According to historical data and archaeological research, cities have existed for at least 5000 years. Since industrialization, the speed of urbanization has been accelerating. This concentration process is manifested in two forms: one is the increase in the number of cities, and the other is the continuous expansion of the population size of each city, thus increasing the proportion of urban population to the total population.
The development of cities at home and abroad shows that urbanization has both positive and negative effects. On the one hand, urbanization can promote economic prosperity and social progress. Urbanization can intensively use land, improve energy efficiency and promote education, employment, health and social services.
On the other hand, while urbanization brings many benefits to people, it also produces a series of serious ecological and environmental problems, which have an impact on the natural ecosystem and people's health. These problems are mainly manifested in three aspects: first, urban climate change (such as heat island effect) and environmental pollution, including water, air, noise and solid waste pollution; Second, the exhaustion and shortage of natural resources, especially the overuse of fresh water, fossil fuels and cultivated land and the reduction of biodiversity; Thirdly, the increase of urban population has led to a large number of social problems, such as housing shortage, traffic congestion, reduction of green space, lagging education and health, among which housing problem has always been one of the main problems faced by many cities.
2. The formation and development of urban ecology
It is precisely because of the above reasons that all countries in the world have begun to attach importance to the ecological construction of cities. Especially since 1992 United Nations Conference on Environment and Development, human settlements have become an important factor to achieve sustainable development. The development of modern cities is getting rid of the traditional development mode centered on architecture and vision in the past and exploring a road of coordinated development between man and nature. Eco-city construction came into being. The new town has put forward new requirements for ecology for many years, and ecology has made new development under such conditions, thus forming a new branch discipline-urban ecology.
As we all know, ecology is a science that studies the relationship between biology and environment. For a long time, ecology is based on natural organisms or ecosystems. After the 1960s, with the increase of the world population and the aggravation of global problems such as resources and environment, ecologists gradually got rid of the initial narrow pure natural tendency and disciplinary limitations in the process of solving social problems, and brought human activities into the research scope, taking the complex system of nature-society-economy as the development direction of macro-field, and made obvious development in theory and research methods, showing strong vitality and a brand-new look.
Urban ecology is an interdisciplinary subject of ecological science and urban science, which was formed in the 1970s. However, ancient human settlements in China, cities in Europe and Indian villages in the southwestern United States all embody the idea of urban ecology.
In 1970s, a group of biologists began to study cities from a biological perspective. Their research focuses on the changing history of animals and plants under the influence of urban environment. In the early 1970s, the first research report published by the Club of Rome was The Limits to Growth. His estimation of the development prospect of world industrialization and urbanization further stimulated people's interest in studying urban problems from the perspective of ecology. 197 1 year, an international research project-Man and Biosphere (MAB) was launched under the leadership of UNESCO. Its purpose is to study the influence of increasing human activities on the whole biosphere and the possible environmental processes and pressures around the world, and to find out the ways and methods for human beings to manage the biosphere reasonably. In addition, the International Ecological Society (INTECOL) established the professional committee of "Urban Ecology" at the first international ecological conference held in The Hague on 1974, and organized and published the quarterly magazine "Urban Ecology". The World Meteorological Organization (WMO), the World Health Organization (WHO), the International Institute of Urban Environment (IIEA), the International Association of Landscape Ecology (IALE), the European Union (EU) and the Organization for Economic Cooperation and Development (OECD) have all carried out relevant research.
China's urban ecology started a little late, but developed rapidly. In the early 1980s, urban ecology was introduced into China, which aroused the extensive interest of ecologists, economists, geographers, urban planners and urban scientists. 1984 12 held the first national symposium on urban ecology in Shanghai, focusing on the research objects, objectives, tasks and methods of urban ecology. 1986 the second national symposium on urban ecology was held in Tianjin in June, focusing on the theoretical research of urban ecology and its practical application in urban planning, construction and management. 1987 10 10 In October, the "Man and Biosphere" Committee of UNESCO held a seminar on the ecology and development of cities and their surrounding areas in Beijing, which created conditions for promoting urban ecological research in China and extensive international exchanges and cooperation. 199765438+In February, the third national seminar on urban ecology and the seminar on urban sustainable development ecology were held in Shenzhen and Hongkong, with the theme of "Exploring the theory, method and practice of urban sustainable development ecology with China characteristics". During the period of 1990, the Chinese Ecological Society held eco-city seminars in Zhuhai and Macau, especially in August 2002, the international eco-city conference was held in Shenzhen, China, and the Declaration on the Construction of Shenzhen Eco-city was discussed and adopted. All these have a far-reaching impact on the development of urban ecology and the construction of eco-city in China.
Urban ecology is a comprehensive discipline based on ecological theory, applying the methods of ecology and engineering, and integrating many disciplines to study the structure, function and dynamics of urban ecosystem with people as the core, as well as the interaction laws between the various components of the system and between the system and the surrounding ecosystem, and using these laws to optimize the system structure, adjust the system relationship, improve the efficiency of material transformation and energy utilization, improve the environmental quality, and realize reasonable structure, efficient function and harmonious relationship.
3. Eco-city construction
The concept of eco-city was put forward in the study of man and biosphere (MAB) initiated by UNESCO. Although related to the concepts of "green city", "healthy city", "garden city", "landscape city" and "environmental protection model city", there are some differences.
Although there is no unified definition at present, eco-city can be understood as a new form of spatial organization to adapt to human social life in the era of ecological civilization, that is, in a certain geographical space, the harmonious and sustainable development of human and natural systems is the advanced stage and form of human settlements (urban and rural) development. The characteristics of eco-city are integrity, harmony, efficiency, diversity and globalization.
Eco-city is a compound system composed of nature, economy and society, and each subsystem restricts and complements each other. Eco-city construction includes the following five levels: ecological security, ecological sanitation, ecological industry, ecological landscape and ecological civilization.
Eco-city requires good regional landscape and ecological environment, rational use of all kinds of land, determination of vegetation coverage and reasonable composition and structure of trees, shrubs and grasses according to local conditions; The atmospheric environment and water environment reach the clean standard, the noise is effectively controlled, and the comprehensive utilization and recovery efficiency of solid waste is high; Protecting biodiversity and its biological environment, integrating artificial environment and natural environment, ecological architecture has been widely used.
Eco-city requires the establishment of an eco-economic system. Ecological economy is a production system based on industrial ecology, including the implementation of ecological agriculture; Realize clean production, and replace terminal pollution control with whole process pollution control; The energy structure is more reasonable, and renewable clean energy has become the main body of the energy structure; In addition, eco-transportation, eco-architecture and eco-tourism are also important components of eco-city economic development.
Establish a new cultural system with "ecological culture" as the core, including the ecologicalization of consumption patterns, that is, sustainable consumption patterns; Advocating ecological civilization; People maintain physical and mental health and human nature is fully developed; Perfect laws and regulations system and high social management efficiency; The social security system and service system are sound, and the comprehensive service ability is strong; Population structure optimization; Convenient transportation.
At present, many different methods are applied to the evaluation of eco-cities. Such as urban ecological footprint method, ecological footprint method, life cycle evaluation method, fuzzy evaluation method, individual index evaluation method and comprehensive evaluation model.
At present, China generally adopts the methods of single index evaluation and comprehensive index evaluation. At present, China is studying the standardization of evaluation indicators. The selection of evaluation indicators is very important, and the following three principles should be followed:
First, representativeness. On the basis of scientific analysis, select representative indicators that can reflect the essential characteristics, complexity and quality level of the city. Second, comprehensiveness. The index system should comprehensively reflect the main characteristics of natural, economic and social systems and their interrelationships, and static indicators should be combined with dynamic indicators. Third, standardization. The selection of indicators should follow the principle of using general indicators recognized at home and abroad, so that the indicators can meet the corresponding specification requirements.
In addition, Hong Kong has successfully applied the method of urban metabolism in the study of urban ecology. In the study of urban ecology such as Guangzhou and Qingdao, the ecological footprint method is introduced.
Look forward
According to the requirements of urbanization development and ecological environment protection, urban ecological research and eco-city construction in the future should focus on the following aspects:
First, pay attention to the exploration of urban ecological theory, especially the research on the structure and function of cities of different sizes; Second, expand the scope of urban scientific research, that is, from the study of a single city to the study of urban-rural complex ecosystem, including the study of semi-urbanized areas and the study of rural industrialization and urban agglomerations; Third, develop the applicable technology system for eco-city construction and promote the ecologicalization of existing technologies; Fourth, provide methodological guidance for ecological landscape planning and ecological culture for the construction of ecological cities; Fifth, establish corresponding policies, decrees and reward and punishment systems to promote the development of eco-cities; Sixth, strengthen the education, training and capacity building of eco-city and enhance ecological awareness; Seventh, strengthen cooperation and exchanges among countries, cities and communities.