EVALUATION OF ENVIRONMENTAL QUALITY OF ATMOSPHERE BY DETERMINATION OF ELEMENT CONTENT IN PLANTS AND SOILS IN TIANJIN
Lin Shun-hua Huang Yin-xiao Yao Yi-qun Han Rong-zhuang (Institute of Botany,Academia Sinica,Beijing)
165 plants and 40 soil samples were collected at seven areas in Tianjin.The analysis of sulphur and heavy metals in these samples showed the polluted degree of the air.It is indica- ted that the plants at smeltery(polluted industry area)contain Zn,Cu,Cd,Pb highest and Ni, S higher.The content of heavy metals in these plants were 3—11 times higher than that of the background value.In business-traffic area and park,the amount of Zn,Cu,Ni,Cd in the plants were 1.5—3.5 times higher than the background value.In the other area,such as culture-education area,road and suburbs,the pollution is not significant,and in the clean area (Panshan),all elements in the plants are the lowest.As to the soils in polluted industry area (Smeltery),the amount of Pb,Cu,Cd,Zn and S was 725,348,9,3 and 14 times higher than that of the background value respectively.Among them,most of Pb,Cu were deposited in sur- face layer.In soil of business-traffic area,Pb,Cu,Cd,Zn and S were 2—10 times higher than the background value,and in the soil of clean area,all elements are also the lowest. The stomata of plants which were blocked by the particles going down from the air.resulted in increase in the stamotal diffusive resistance and the order of the resistance in the different places are as follows:polluted industry areasparksbusiness-traffic areasroadclean areas. These results are in agreement with the polluted state of the plants and soils in above mention- ed areas.