Urban soil research has aroused great attention in recent year s. Previous studies were mainly focused on urban soil physics
and chemistry, soi l geography to constrain the source, distribution, transport and deposition of p ollutants such as heavy metals, hazard organic matter, but little work is relate d with soil microbiology. In this paper, the authors report the variation of mic robial features in urban soils as compared with adjacent rural areas. The result s show significant changes in basal
respiration rate, microbial biomass and ecop hysiological parameter in the urban environment because of the anthropogenic str ess. Rural soils are obviously large in size of microbial community than urban s oils, as indicated by microbial biomass, but apparently lower in microbial respi ration strength expressed by respiration rates, and also have lower C-mic/C -org and metabolic quotient (qCO-2) values, which gave lower level and sta ble microbial activity in rural soils, thus activating the microorganisms to con sume much more energy carbon but in lower utilization efficiency. So microbial b iosensors can effectively indicate the environmental transition from rural area to urban condition under stress of
heavy metal pollution.