Introduction Of Swedish Energy Energy And Its Enrichment And Adaptation To Heavy Metal Cadmium

Salix 1（Salix dascladus）,Salix 2（Salix dascladus）,Salix E（Salix viminalis）, Salix C（Salix fragilis）,Salix S（Salix sino-purpurea）,Salix M（Salix matsudana）as the studied object,their adaptability was evaluated by planting them in two nurseries of Tianjin and their Cadmium resistance and accumulation ability also be studied by determining their ecophysiological responses under Cadmium stress.The primary results were as follows:1.Energy willow clones grew quickly from May to August,and their growth biomasses were more than three times of Salix S.The evaluated result of their adaptability was Salix E＞Salix C＞Salix 2＞Salix S.2.For the growth biomass,Salix E、Salix C were restrained less and Salix M、Salix 1 were restrained more under the higher Cadmium concentration.With increasing Cadmium concentration,the root-mass ratio and the root-shoot ratio of five clones increased first and then declined,but the leaf-mass ratio declined first and then increased.3.The contents of chlorophyll and chlorophyll a were more than the control under the lower Cadmium concentration,but the higher Cadmium concentration inhibited the synthesization of chlorophyll.With increasing Cadmium concentration, the average value of net photosynthetic rate and stomatal conductance of 4 clones increased first and then declined basically,but the transpiration rate declined and the water use efficiency increased.4.Generally,the activity of SOD,POD,CAT and Root increased first and then declined.However,the CAT activity of every willow clones changed not much under different Cadmium concentration.For Salix E and Salix C,the activity of SOD and40 mg.kg^-1Cadmium concentration,but other three clones first declined significantly under lower Cadmium concentration.5.With increasing Cadmium concentration,the Cadmium contents of 5 willow clones’ roots all increased,the Cadmium contents of their shoots and leaves increased first and then declined,but their accumulation coefficients declined basically.The distribution of Cadmium in clones was root＞shoot＞leaf.Salix E、Salix C’s Cadmium accumulation ability was stronger in root and shoot,and Salix 2’s leaf had the strongest Cadmium accumulation ability.6.Subordinate function analysis suggested that the tolerance of 5 willow clones to soil Cadmium contamination was in order of Salix E＞Salix C＞Salix M＞Salix 2＞Salix 1.In summary,Salix 2、Salix E、Salix C grew well in Tianjin and could be planted more to acquire energy and beautify city;Salix E、Salix C have stronger Cadmium resistance and accumulation ability,thus they could remedy the Cadmium polluted soil.