Effect of biochar on the solidification of cadmium in soil and the growth of leek

LIU Hui; SUN Xiulan

doi:10.3969/j.issn.1673-2871.2023.12.017

Abstract：To investigate the effects of biochar on the different forms of total cadmium and cadmium in soil,soil chemical properties,and the growth of Chinese chives,we used potted plants with added cadmium chloride(CK)as a control and set up three different ratios of biochar treatment:1％biochar+cadmium chloride(T1),2％biochar+cadmium chloride(T2),and 5％biochar+cadmium chloride(T3).The biomass of Chinese chives during and after harvest,the total cadmi-um content in the soil,and the proportion of different forms of cadmium,soil chemical properties and other indicators were measured.The results showed that compared with CK,adding different proportions of biochar improved soil chemi-cal properties and significantly increased soil pH;the biomass,plant height,and root length of leeks significantly in-creased;reduced the proportion of exchangeable cadmium in soil,increased the proportion of iron manganese oxide bound cadmium,organic matter bound cadmium,and residual cadmium,thereby reducing the total cadmium content in plants.Among them,T2 treatment has the best effect on improving the quality of leeks and reducing the cadmium content in various parts,compared with CK,soil pH was significantly increased by 0.53-1.23,the biomass of leaf,stem and root were significantly increased by 17.3％-32.6％,20.1％-58.6％,15.6％-30.5％,plant height and root length were significant-ly increased by 4.4％-12.3％and 12.6％-26.0％,respectively,the total cadmium content in leaves,stems and roots de-creased by 66.4％-93.6％,71.3％-92.7％and 28.7％-59.0％,respectively,which can be promoted and applied in practical production.