摘要
修复效率低一直是植物修复技术需要解决的关键问题之一.基于我国的CO2减排压力和CO2对植物生长的必要性,选择C3植物绿豆和C4植物玉米作为修复植物,以DEHP为目标污染物,探索增施CO2对植物修复土壤DEHP污染的影响.结果表明:DEHP对两种植物生长和根际微环境都产生了抑制性影响.增施CO2后,两种植物地上干质量显著增加,叶片SOD酶活性明显下降,根际土壤碱性磷酸酶活性增加,根际微生物群落结构改变,根际耐DE-HP胁迫微生物数量增加,表明增施CO2对促进植物生长、增强植物抗DEHP胁迫能力、改善根际微环境有积极作用.增施CO2还促进了两种植物对DEHP的吸收,特别是植物地下部分.这些共同作用导致增施CO2后的两种植物根际DEHP残留浓度明显下降,土壤污染植物修复效率提高.整体上看,增施CO2对C3植物绿豆的影响明显大于C4植物玉米.可以将增施CO2作为强化植物修复过程的措施之一.
Low efficiency of remediation is one of the key issues to be solved in phytoremediation technology. Based on the necessity of reducing CO2 emission in China and the significance of CO2 in plant photosynthesis, this paper studied the effects of enhanced CO2 fertilization on the phytoremedi- ation of polluted soil, selecting the C3 plant mung bean (Vigna radiate) and the C4 plant maize (Zea mays) as test plants for phytoremediation and the DEHP as the target pollutant. DEHP pollu- tion had negative effects on the growth and rhizosphere micro-environment of the two plants. After enhanced CO2 fertilization, the aboveground dry mass of the two plants and the alkaline phosphatase activity in the rhizosphere soils of the two plants increased, the COD activity in the leaves of the two plants decreased, the microbial community in the rhizosphere soils shifted, and the numbers of the microbes with DEHP-tolerance in the rhizosphere soils increased. These changes indicated that en- hanced CO2 fertilization could promote the plant growth and the plant tolerance to DEHP stress, and improve the rhizosphere micro-environment, Enhanced CO2 fertilization also increased the DEHP uptake by the two plants, especially their underground parts. All these effects induced the residual DEHP concentration in the rhizospheres of the two plants, especially that of mung bean, decreased obviously, and the phytoremediation efficiency increased. Overall, enhanced CO2 fertilization pro- duced greater effects on C3 plant than on C4 plant. It was suggested that enhanced CO2 fertilization Could be a useful measure to enhance the efficiency of phytoremediation.
出处
《应用生态学报》
CAS
CSCD
北大核心
2013年第3期839-846,共8页
Chinese Journal of Applied Ecology
基金
中央高校科研业务费专项(ZZ1106)资助
关键词
植物修复
DEHP
增施CO2
残留浓度
phytoremediation
DEHP
enhanced CO2 fertilization
residual concentration.