Urban soils act functionally as an ecological screen in protecting urban environment.Their degradation,however,is in essence a process of providing ecological services,such as sink of all kinds of pollutants,at the cost of their own quality.Therefore,as a result,they often come across a variety of environmental problems.Besides physical degradation,such as compaction,enrichment of various elements associated with human activities,heavy metals,and organic pollution are the major problems with urban soil environment.The main features of urban soil contamination are characterized firstly by strong accumulation of socalled ‘urban elements' such as Cu,Zn,Pb and Hg,but less of other heavy metals;and secondly by spatial isolation,which means the contamination is not spatially continuous.During the process of urban development,heavy metal contamination of urban soils happens not only nowadays,but also did in the past,especially when primitive mining and metal processing prevailed.Furthermore,urban soils are often polluted by organic pollutants,especially polycyclic aromatic hydrocarbons (PAHs),with roadsides and industrial sites being the major vulnerable areas.PAHs therein have normally 2～6 rings and predominantly 2～4 rings,strongly suggesting their pyrogenic background,including motor vehicles,industrial activities and coal burning. So far,studies on urban soil contamination and other related environmental problems have concentrated mainly on three aspects,firstly source,status and diffusion patterns of urban soil contamination;secondly impact and risk assessment of soil contamination on environment,ecology and biological health;thirdly better use and management of urban soils.More researches are expected in the coming near future on environmental capacity of urban soils,threshold values and dynamics of translocation of these contaminants,interactions between soil,water and organisms,and biological effects of pollution. These studies are important to the establishment of a science-based risk assessment system for urban soil environment,soil pollution control and better management of urban soils and environment.
张甘霖,赵玉国,杨金玲,赵文君,龚子同.城市土壤环境问题及其研究进展[J].土壤学报,2007,44(5):925-933. DOI:10.11766/trxb200605310523 Zhang Ganlin, Zhao Yuguo, Yang Jinling, Zhao Wenjun, Gong Zitong. URBAN SOIL ENVIRONMENT ISSUES AND RESEARCH PROGRESSES[J]. Acta Pedologica Sinica,2007,44(5):925-933.复制