Deng Lin, Li Zhu, Wang Jie, Liu Hongyan, Li Na, Wu Longhua, Hu Pengjie, Luo Yongming, Christie Peter
a Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences , Nanjing , China.
b College of Resources and Environmental Engineering, Guizhou University , Guiyang , China.
Int J Phytoremediation. 2016;18(2):134-40. doi: 10.1080/15226514.2015.1058328.
In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.
在两项长期田间试验中，对锌（Zn）/镉（Cd）超富集植物东南景天（Sedum plumbizincicola）进行了研究，以通过与玉米（Zea mays）间作和种植密度这两种农艺策略来优化对金属污染土壤的植物提取。长期植物提取后，土壤总锌和镉浓度显著降低。但地上部生物量以及镉和锌浓度并未随修复时间的增加而表现出显著差异。在间作试验中，“东南景天与玉米间作”处理的植物修复效率高于东南景天单作，且玉米的镉浓度低于国家最大限量。在种植密度试验中，植物修复效率随种植密度的增加而提高，每公顷440000株时达到最大速率。这些结果表明，以适当种植密度种植并与玉米间作的东南景天能够在不影响谷类作物生产力的情况下，对污染土壤实现较高的修复效率。这种种植系统将充足的农业生产与土壤重金属植物提取相结合。
