生物炭对镉铅污染土壤中金银花生理特性及镉铅积累的影响

Influence of Biochar on Accumulation of Soil Cd and Pb in and Physiological Characteristics of Lonicera japonica

采用盆栽试验,研究了镉铅污染土壤中添加生物炭对金银花生理特性及其镉铅积累的影响。结果表明:添加2%~16%的生物炭处理可显著增加金银花的净光合速率、叶绿素含量和根系活力,明显降低其SOD活性;添加6%~16%的生物炭时金银花根部与茎部的镉与铅的含量均显著下降;添加2%~16%的生物炭时金银花叶部与花中的镉与铅的含量均显著下降。添加8%以上的生物炭能使金银花花中的镉与铅的含量降低到安全范围。

To investigate the effects of biochar on plant physiological characteristics and inhibition of heavy metal accumulation in plant organs,Lonicera japonica was used as plant material in a pot experiment,in which biochar was added into artificially Cd-and Pb-polluted soil at 0%,2%,4%,6%,8%,10%,12%,14% and 16% of biochar-soil dry weight ratio gradients.Net photosynthetic rate,chlorophyll content,root activity,SOD activity,and heavy metal contents in roots,stems,leaves and flowers were evaluated.The results showed that the addition of 2%-16% biochar into potting soil significantly increased net photosynthetic rate,chlorophyll content and root activity,and decreased SOD activity.Adding 6%-16% biochar significantly decreased Cd and Pb contents in roots and stems (P<0.05).Adding 2%-16% biochar significantly decreased Cd and Pb contents in leaves and flowers (P<0.05).Considering several indicators,the optimum ratio of biochar to soil is more than 8% for Lonicera japonica,which can significantly reduce Cd and Pb contents in flowers of Lonicera japonica to the medicinal plant safety standard.