Study On Resistance And Tolerance Of Eulaliopsis Binata To Heavy Metal

This experiment has studied the effects of nine levels of combination pollution of cadmium (Cd) and lead (Pb) on growth and physiology oi Eulaliopsis binata, as well as on restoration of Cd and Pb. The aim was to estimate the tolerance to them and make ourselves understand environmental value of Eulaliopsis binata. The main results were as follows:1. The results suggested that Eulaliopsis binata have a better absorption capacity of Cd than Pb. And the content of the two metals in root was higher than that in aboveground. In the treatments which was more than 20 μg·g^-1 Cd, the root absorbed 87.73-209.64 μg·g^-1Cd. This indicated it was close or above critical levels for Cd hyper-accumulator (100 μg·g^-1) . While among all the treatments, the aboveground part had absorbed 1.21-16.56 μg·g^-1Cd. And this was far way from critical levels for hyper accumulator. The root absorbed 112.46-864.68μg·g^-1Pb, while aground part absorbed 4.56-27.78 μg·g^-1 below critical levels for Pb hyper-accumulator (1000 μg·g^-1. The accumulating index of Pb were between 28.88 and 222.81, while that of Cd were from 5.24 to 58.51. This demonstrated Eulaliopsis binata have a higher accumulating capacity of Pb than Cd. When the content treatments of Pb was definite, the content of Cd in the plant increased with the content of Cd in the soil; at the same time, when the content treatments of Cd was definite, the content of Pb in the plant increased with the content of Pb in the soil.2. The combined pollution of Cd and Pb produced slight negative effects on the growth of Eulaliopsis binat. With increasing of combined Cd and Pb pollution, the tillage number, root length, shoot height, and biomass decreased unobviously3. Under compounded pollution of Pb and Cd, the content of chlorophyll in leaves was less than that of the CK obviously. Cd contributed more to chlorophyll than that Pb. The compounded pollution of Pb and Cd gave different effects on three protective enzymes. The activity of SOD in plant were activated by lower or mediate content of heavy metals and inhibited by higher content; The activity of POD showed remarkably decrease, the activity of CAT was promoted in major conditions. Hence, CAT gave main protection for the plant. On the present respect, Cd produced heavier damage to the...