| With a rapid increase in industrial activities and urbanization, pollution derived from uncontrolled escapes of heavy metals such as cadmium, lead, chromium, copper, nickel, and zinc, has become serious. Assessing environmental pollution using plants has been proved to be a complementary method of investigation for pollutant analysis, and mosses, leaves of plants and tree barks have been used as bioindicators of atmosphere heavy metal pollutants in numerous studies. The analysis and comparison on leaves, tree bark, moss bags and live mosses monitoring technology carried out, and it is suggested that optimal monitoring technology could be used as bioindicator in monitoring for the heavy metal pollution in Nanjing, to monitor and study the status and it's change of heavy metal pollution in Nanjing. The main results are as follows:(1) The analysis and comparison on heavy metal contents in leaves and barks of different trees on the pollution zone and clean zone were carried out. The results showed that different species'leaves and barks had different adsorptive ability to the same metal, and the same species'leaves and barks had different adsorptive ability to the different heavy metals. Leaves of Populus deltoides, Cedrus deodara and barks of Liriodendron chinese, Cinnamomum camphora have high absorption capacity to heavy metals. Based on heavy metal average contents, the analysis and comparison on barks micromorphology of different trees on the pollution zone and clean zone were carried out. The results showed that rough barks had higher cumulative capacity than smooth bark, and the heavy metal adsorption capacity of tree barks had a relationship closely with micromorphology structures of tree barks. The analysis and comparison of the contents of Cd, Cr, Cu, Ni, Pb and Zn in the plants of 19 different species of bryophytes at Zijin Mt. on three different habitats were carried out. The results showed that different species of bryophytes had different adsorptive ability to the same metal, and the same bryophyte had different adsorptive ability to the different heavy metals, in which the Ptychomitrinm sinense had the highest absorption capacity to heavy metals in study mosses. According to the principle that monitoring plants should be widely distributed and based on actual survey, it is suggested that the moss Haplocladium could be used as bioindicators in monitoring heavy metal pollution in Nanjing.(2) The analysis and comparison on heavy metal contents in 5 kind materials of moss bags hunged on the pollution zone and the clean zone was carried out, and it is suggested that the mosses Hypnum plumaeforme and Sphagnum junghuhnianum could be used to study adsorption dynamics in monitoring heavy metal pollution in Nanjing. The results showed moss bag adsorption increased gradually with increasing time, and heavy metals contents of Cd, Cr, Cu, Ni, Pb and Zn showed a rising trend in 1~6weeks, therefore it is suggested that the hunging time of moss bags should be 6 weeks in air environmental conditions of Nanjing city. The analysis and comparison on time-varying model of heavy metal contents in several organs of Platanus hispanica on the pollution zone and clean zone were carried out. The results showed that the heavy metal contents in the pollution zone were significantly greater than what in the clean zone, and presented a different time variation. Besides that, the accumulative effect of bark and leaves was founded be more apparent than other organs.(3) The analysis and comparison on heavy metals content distribution in different organs, leaf tissue, annual and biennial r branches, and subcell of leaves of Platanus hispanica collected on the pollution zone and the clean zone were carried out. The results showed leaves and tree barks of Platanus hispanica have high absorption capacity to six kinds of heavy metals. Furthermore, concentration measure of tissues of Platanus hispanica leaves to these heavy metals was markedly different, and the concentration measure order was as follows: lower epidermis>upper epidermis, and sponge tissue>palisade tissue. Finally, the pollution index for cytoplasmic supernatant fraction of leaves is the largest, and Cr, Cu, Ni, Pb and Zn accumulates in the leaves where it is primarily distributed in the cytoplasmic supernatant fraction.(4) By means of ICP method, the contents of Cu, Pb, Zn, Cd, Cr in moss Haplocladium plants, leaves and tree barks of Platanus hispanica, Sphagnum junghuhnianum bags and corresponding soils at 10 monitoring sites in Nanjing city were measured. The correlations of the heavy metals'contents between these monitoring materials and the soil as well as the concentration of PM10 in the air were analyzed. The results indicated that some correlations were existed in these monitoring materials and corresponding soils, but there were more prominent correlations between the contents in these monitoring materials and the concentration of PM10. Moreover, heavy metal content of Haplocladium plants and moss bags in these monitoring materials had significant correlation with the concentration of PM10. It is suggested that the concentration of PM10 could be monitored by measuring the heavy metal contents in moss plants. In order to pick out the fine species for transportation pollution monitoring, some representative greenery species in Nanjing were chosen to systematically study the heavy metal elements (Pb, Cd and Cu)accumulation and physiological indexes (souble protein, praline content and MDA)changes in the leaves of 14 different tree species in the arterial roads and the suburb roads by chemical analysis method and physiological index determination method. The results showed that the heavy metal contents in the arterial roads were significantly greater than what in the suburb roads, which meaned transportation pollution was becoming more serious. Meanwhile, souble protein, praline content and MDA level on the arterial roads were much higher than suburb roads in general as well, which could be suffers from transportation pollution. According to the physiological indexes and heavy metal contents differences, Prunus cerasifera, Cedrus deodara, and Populus deltoides are founded as fine species for transportation pollution monitoring. Besides that, their functional types were divided based on relatively difference percentage of tree species'heavy metal content.(5) The contents of Cd, Cr, Cu, Ni, Pb and Zn in moss Haplocladium plants at 47 monitoring sites in Nanjing city were measured by means of ICP method.The relationship between the contents of heavy metals in the plants and environment factors were analyzed with average linkage cluster analysis method. The results indicated that the 47 monitoring sites could be divided into three groups of sites with different degree of heavy metal pollution, and there were some correlations to the degree of environmental pollution. By means of Kriging method, the isoline distribution maps of the heavy metals'contents were made. The maps showed that the heavy metal pollutions were heavy in center, and light pollution in suburban of Nanjing city, as were heavy in where have chemical plants and heavy traffic.(6) The contents of Cd, Cr, Cu, Ni, Pb and Zn in moss Haplocladium plants at different altitudes, in the North-west Zijin Mt. of Nanjing city were measured by means of ICP method. The results showed element concentrations did vary with altitude in related to elevation, and there were more prominent positive correlations between the contents in moss Haplocladium plants and altitude. Cd and Cu concentrations in moss Haplocladium plants were the highest in mid elevation, and this might change of moss at different altitudes. While Cr, Ni, Pb and Zn concentration generally increases with altitude within small Zijin Mt. areas, and this might be with relation to high contents of fine particles at high-altitude and diffusion conditions in summer.(7) The analysis and comparison of the contents of Cd, Cr, Cu, Ni, Pb and Zn in the leaves of Platanus hispanica and Pittosporum tobira historical specimens and fresh materials collected in 2006, 2009 at 14 different sites by means of ICP method was carried out. The results showed that the concentrations of the 6 heavy metals at all sample sites increased gradually from 1920's to 2009. By means of Kriging method, the isoline distribution maps of the heavy metals'contents in leaves of Platanus hispanica for different years were made.The changes of concentrations of the heavy metals especially in Zhongshan plant garden on Zijin Mt., Nanjing university and the heavy metal average contents of two species in different years were analyzed with Two-Factor analysis of variance and Linear regression method respectively. The results showed the concentrations of the 6 heavy metals at two sample sites increased gradually from 1920's to 2009, as well as heavy metal average contents in two trees'leaves. The increasing rate was Pb>Zn>Cu>Ni>Cr>Cd, which should be strengthened Pb pollution control because of it's the highest rising rate.
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