The Effect Of Biochar On The Quality Of Pakchoi And The Accumulation Of Heavy Metal Cadmium

Due to the acceleration of industrialization,heavy metal pollution caused by industrial waste water,waste gas and waste slag is serious.Excessive fertilization in agriculture and the application of manure with excessive heavy metals may cause heavy metal pollution to the soil.In this paper,biochar is used to improve the soil environment and the quality of vegetables by utilizing the adsorption of heavy metals by biochar.By understanding how the application of biochar changes the form and migration capacity of heavy metals in the soil,high-efficiency and economical heavy metals are established.To provide scientific basis for rational utilization of biochar to remediate heavy metal contaminated soil and safe production of vegetables.In this paper,potted Chinese cabbage with different biochar was used as the research object.By measuring the quality of Chinese cabbage and the change of heavy metal content in soil under different treatments,the optimum adsorption concentration of biochar on heavy metals was screened.Parallel experiments were conducted to verify the effect of biochar on the quality of Chinese cabbage and the adsorption effect of heavy metal Cd in organic manure.Get the following conclusions.?1?Different concentrations of biochar promoted the growth and quality of Chinese cabbage.The plant height,chlorophyll,soluble protein and cellulose content of Chinese cabbage reached the maximum under T₂ treatment.The VC content and soluble sugar content of Chinese cabbage under T₃ treatment reached significant effect,which increased 81.08%and 136.86%respectively compared with the control.The nitrate content of the plant was significantly reduced by biochar concentration,and the reduction effect of T₂ treatment was the most significant,which was 13.61%lower than that of control.?2?Organic fertilizer and compound fertilizer promoted the growth and quality of Chinese cabbage to a certain extent.The root length,chlorophyll,soluble sugar and nitrate content of F₁treatment with compound fertilizer reached significant levels,which increased by 26.46%,35.85%,72.39%and 53.06%compared with the control.?3?The soluble protein content and VC content of F₂ treatment with 2.5%chicken manure were 9.33 mg·g^-1and 6.43 mg·100g^-1,respectively,which increased by 58.17%and 43.37%compared with the control.?4?The addition of biochar could promote soil enzyme activity,urease activity and phosphatase activity under T2 treatment increased by 147.93%and 154.96%respectively compared with the control.?5?The lowest activity of urease and dehydrogenase was 1.16 mg·g^-1and 28.90 mg·g^-1under the treatment of F₃ with 5%chicken manure organic fertilizer,which were 31.40%and54.24%lower than the control,respectively.The activities of phosphatase and invertase were significantly increased by 0.49 mg kg^-1and 48.80 mg·kg^-1,respectively,which were 13.95%and218.95%higher than the control.?6?Biochar can adsorb heavy metal Cd in soil.The adsorption effect of 3%biochar concentration is more significant.The content of heavy metal in roots of plants is significantly higher than that in leaves.Chicken manure organic fertilizer can increase the content of heavy metal Cd in plants and soil.The higher the concentration of heavy metal Cd,the higher the content of heavy metal Cd in leaves,roots and soil under F3 treatment,the heavy metal content in leaves,roots and soil is 0.33 mg·kg^-1,0.51mg·kg^-1and 0.34mg·kg^-1respectively,increased 0.21mg·kg^-1,0.33 mg·kg^-1and 0.19 mg·kg^-1,which were significantly higher than those of the control.In summary,Biochar,NPK compound fertilizer and organic fertilizer can promote the growth of plant height,root length and other growth indicators of Chinese cabbage,and the accumulation of nutrient quality such as soluble sugar,soluble protein and VC.The application of NPK compound fertilizer and chicken manure organic fertilizer could increase the nitrate content of Chinese cabbage,while biochar could significantly inhibit the nitrate accumulation.The effect of applying biochar to improve soil nutrient content and soil enzyme activity was better than that of applying NPK compound fertilizer and chicken manure organic fertilizer.Biochar can effectively adsorb Cd in plant and soil,and the adsorption effect of T₂ treatment is more significant.The application of organic fertilizer increased the content of heavy metals in plant and soil,and chicken manure organic fertilizer significantly increased the content of heavy metals in leaves,roots and soil of pakchoi,with F₃ increasing the most significant effect.