3种园林植物对土壤重金属Cd的吸收及修复研究

以自来水处理作对照,采用土培法研究了3种Cd处理浓度下棕竹、宛田红花油茶、博白大果油茶对土壤重金属Cd的吸收及修复能力,为Cd超积累植物的筛选及土壤Cd污染治理提供依据。结果表明,与对照组（0 mg.kg-1）相比,10、25、50 mg.kg-1 Cd处理45 d后,3种园林植物均能较好生长,未出现任何中毒症状;10、50 mg.kg-1 Cd处理浓度下,3种园林植物地下部（根系）Cd含量均大于地上部（茎、叶）,且随着Cd处理浓度的增大,地下部（根系）Cd含量增幅均大于地上部（叶、茎）,其中棕竹根系Cd含量增幅最大,是10 mg.kg-1处理的7.05倍;在10～50 mg.kg-1处理浓度范围内,3种园林植物地上部与地下部Cd含量比值均较低,且Cd在3种植物体内的迁移率均随处理浓度增大而降低。

Phytoremediation properties of three ornamental plants for cadmium absorption in soils

An experiment was conducted to investigate the phytoremediation properties of three ornamental plants viz.,Rhapis excelsa,Camellia polyodonta and Camellia gigantocarpa for soil cadmium（Cd） absorption in order to provide references for Cd hyperaccumulating plant screening and soil pollution control.The experiment was conducted in soil-pot culture system and plants were treated with Cd（10,25 and 50 mg·kg-1）.The results showed that all ornamental plants grew well and did not showed any toxic symptoms in soils while containing 10,25 and 50 mg·kg-1 cadmium compared to control.When the cadmium concentrations were 10 and 50 mg·kg-1,the Cd contents in the underground parts（roots） of three ornamental plants were all higher than that in the aboveground parts（stems and leaves）.With the increasing cadmium concentration,the increasing rates of cadmium contents in the underground parts（roots） of three ornamental plants were all higher than that in the aboveground parts（stems and leaves）.The Cd content in the roots of the Rhapis excelsa at 50 mg·kg-1 Cd concentration was 7.05 times higher than that at 10 mg·kg-1 cadmium concentration and its increasing rate of cadmium content was the highest amongst all ornamental plants.The ratio of cadmium contents in aboveground part to underground part in all ornamental plants were low and their mobility decreased with increasing cadmium concentration in the soil.