Study Of The Effect Of Tea Saponin On Remediation Of Cadmium And Zinc In Soil

Tea saponin is a kind of biosurfactant and has the characteristic of good biodegradation and large surfactivity. Its application in soil heavy metal pollution restoration is a new research in recent years The purpose of this thesis is to discuss probe into the safety effectiveness of tea saponin and provides foundation for Scientific and reasonable utilization of tea saponin repair soil heavy metal, by the research of rapeseed seedling growth and physiological properties with tea saponin,the absorption of soil heavy metal and the influence of soil enzyme activity with tea saponin. Main research results are as follows:(1) In hydroponic nutrient with the concentration of Cd for 5, the heights and the weights of rape with tea saponin concentrations were first rised then reduced.(2) In hydroponic nutrient with the concentration of Cd for 5, the activities of SOD and CAT of the rape leaves with tea saponin concentrations were first rised then reduced. Tea saponin in low concentration range can ease rape poison of Cd, improve the system of rape leaves antioxidant enzymes , and partly lighten the rape leaves plasmalemma peroxide level.(3) In the Cd, Zn pollution of soil, with tea saponin concentration increases, rapeseed height and dry weight first reduce and then rise . From the tea saponin concentration of 0.5 mmol·kg-1, rape plant height and dry weight are higher than comparison group. Therefore, the tea saponin in certain concentration range can mitigate rapeseed growth of Zn, Cd poisons.(4)Adding the tea saponin to soil doesnot affect the form of soil Zn, but mitigating toxieity was most signifieant,but can increase oxidation and extract weak Cd content, thereby improving the Cd biological toxicity.(5)The distribution of plants for the root > stem after Cd, Zn absorbed in rapeseed. Tea saponin change the distribution of Cd, Zn in rapeseed,and more transfer from root to stem ang leaves. The Cd concentration ability is stronger than Zn, and the rape root concentration Cd, Zn also higher than cauline leaf.(6)Tea saponin can reduce soil urease activity, but can improve soil catalase activity.