Research On The Response Mechanism Of Euonymus Japonicus To Compound Pollution Of Atmospheric SO₂-Pb

Currently,air pollution is one of the major environmental crises facing mankind,hindering the sustainable development of human society.Atmospheric SO₂-Pb complex pollution is a serious threat to people's life and health,and effective treatment is the key to improve the atmospheric environment.Eco-recovery of vegetation technology to purify compound pollution of atmospheric SO₂-Pb,which is regarded as secure and environmentally friendly atmospheric governance technology with landscaping function,has been the current ecology and landscape garden research frontier hot spots.In this paper,based on the study of the symptoms of atmospheric SO₂-Pb complex polluted area,the contents of S and Pb in leaf and the related physiological and biochemical indexes?POD activity,pH,etc.?were studied by using field sampling method.As three times repetitive randomized block design of experiment,the samples of Euonymus japonicus were sampled in compound pollution of atmospheric SO₂-Pb area and non-polluted area.Based on the analysis of variance,multiple comparison,correlation analysis and principal component analysis on that,the response mechanism of Euonymus japonicus to compound pollution of atmospheric SO₂-Pb was revealed on cellular level,which laid a theoretical foundation for the ecological restoration of compound pollution.Conclusion for the research indicates:1.Damage characteristics and resistance to atmospheric SO₂-Pb complex pollution of Euonymus japonicus: Under atmospheric SO₂-Pb combined pollution stress,the leaves of Euonymus japonicus did not appear obvious injury symptoms and normally grow.Euonymus japonicus showed strong resistance to atmospheric SO₂-Pb complex pollution.2.The research of the response mechanism to atmospheric SO₂-Pb complex pollution for Euonymus japonicus shows:?1?The Chl content,MDA content,O2-production rate,POD activity,APX activity,SS content and SP content of Euonymus japonicus leaves were significantly affected by atmospheric SO₂-Pb pollution,but no significant effect on pH.Chl content was lower than that of nonpolluted area,while POD and APX activity,MDA,soluble sugar and soluble protein content and O2-production rate all increased.?2?The content of Chl in Euonymus japonicus leaves was negatively correlated with O2-production rate,POD and APX activity and soluble sugar content;And negatively correlated with soluble protein content.The soluble protein content was positively correlated with POD and APX activity and soluble sugar content.There was a significant positive correlation between the production rate and the POD activity and the soluble protein content,and was positively correlated with the content of MDA.The APX activity was positively correlated with the soluble sugar content,but negatively correlated with the pH value.?3?In the first principal component,the absolute value of MDA content,POD activity and O2-generation rate was higher.In the second principal component,the pH value,soluble sugar content and APX activity load were higher.3.Study on purification response mechanism of Euonymus japonicus to SO₂-Pb complex pollution in atmosphere shows :The difference of S and Pb contents of Euonymus japonicus leaves in different areas was extremely significant.Under atmospheric SO₂-Pb combined pollution stress,the S and Pb contents in Euonymus japonicus leaves were significantly higher than those in non-polluted areas,and there was a moderate positive correlation between the them.Atmospheric SO₂-Pb complex pollution,SO2 and Pb diffusion into Euonymus japonicus leaves could destroy the chlorophyll structure,increase the intracellular reactive oxygen species and change the membrane permeability.Euonymus japonicus would improve the resistance to SO₂-Pb complex pollution mainly through enhancing POD,APX and other antioxidant enzyme activity,speeding up the rate of reactive oxygen scavenging to protect the cell membrane system and by increasing the soluble sugar,soluble protein and other osmotic regulation substances to maintain cell pH and osmotic pressure stability.