城市化的生态风险及其管理

摘要

城市化体现在人口向城市聚集和城市景观扩张的同时,社会结构发生了极大变化,城市生产生活方式向更加广泛的地区扩散.然而,随着人口的过度密集和城市的日益扩张,交通拥堵、空气污染、废物堆积、流行病肆虐等“城市病”频发.城市通过大量汲取和消耗自然资源,向周围环境排放大量污染物,改变了区域生态系统的原有结构和功能,产生了严峻的生态风险,进而制约着城市生态系统的可持续发展.城市化的生态风险正逐步得到广泛关注,但对其具体的内涵和影响尚不明晰.归类描述了城市化过程中面临的各种生态风险,分析了导致生态风险的主要因素,阐述了辨识与评价生态风险的基本方法,提出了城市化生态风险的调控管理对策.%With urbanization,not only population is gathering to the city and urban landscape is expanding,but also social structure is changing greatly.At the same time,urban modes of production and consumption are spreading to a wider area.However,with over-concentrated population and extensive expansion of cities,"urban diseases" such as traffic congestion,air pollution,waste accumulation and epidemics occur frequently.City consumes natural resources excessively and discharges a large amount of pollutants to the surrounding environment,which will change the original structure and function of regional ecosystem,and then severe ecological risks emerge and the sustainable development of urban ecosystem is constrained.The ecological risks of urbanization have been gradually getting more attention,but the concrete definition and impacts of urban ecological risks are still unclear.Therefore,this paper defines all kinds of ecological risks and analyses their main influencing factors in the process of urbanization.The major methods for ecological risk identification and assessment are also expounded,and some suggestions for ecological risk management of urbanization are presented.