The Change Of Physiology And Ultrastructure Of Epiphytic Bryophytes Under Different Air Pollution Level

Two Pterocarya stenoptera epiphytic bryophytes Entodon compressus C. Muell. and Haplocladium microphyllum(Hedw.) Broth, under long range of air pollution in different places in Nanjing are used to evaluate the degree of pollution conditions in different areas by analyzing the contents of heavy metal and element S. The relation between the changes of epiphytic bryophytes physiological and biochemical criterion and the changes of ultrastructure under different pollution gradients are also studied in this thesis.Analyzing the contents of contaminants of Entodon compressus C. Muell. in different sampling points, we can evaluate their pollution status. The results are concluded as follows: (1) Xiashu forestry farm and Zijin Mountain are belong to clean areas, (2) Nanjing Forestry University and Qingliang Hill are belong to slightly polluted areas, (3) Jiuhua Hill and Zhujiang Road are belong to moderate polluted areas, (4) Nanjing chemical factory, lipid chemical factory and Qixia refinery are belong to heavy polluted areas.We take the Entodon compressus C. Muell as an example to study the changes of physiological and biochemical index under different pollution level. We concluded that the total content of chlorophyl is decreasing as the air pollution is increasing. So is the content of chlorophyl a and chlorophyl b. The more serious the degree of pollution is, the lower the ratio of chlorophyl a and chlorophyl b is. At the same time the content of dissoluble sugar is increasing while the dissoluble proteins go through a procedure of increasing at first and decreasing as the pollution come to a certain degree. The activity of POD and SOD suffers the same procedure.The appearance of Entodon compressus C. Muell in the clean areas is as follows: Its blades are neat and extend; the surface of the blades are clean. As the aggravation of the pollution, the blades wind and shrink and there is also a large amount of particles attach to the surface of the blades. Viewing from the cytoarchitecture, as the pollution aggravating, the cholorplasts of the Entodon compressus C. Muell expand, the slices of internal capsule disappear, capsules rupture, some cholorplasts even disintegrate; The ridge of the mitochondrion expand to roundness, some of the ridge even disappear, some of the mitochondrion became transparent and then disappear at last; The nucleus distort, the nuclear membrane invaginate and rupture, nuclelus disperse, chromatic agglutination, some parts of the nuclear membrane dissolve, karyoplasms give off into the cytoplasm; the cell wall is thinning...