Effect And Mechanism Of Biochar On Soil Remediation Of Plumbum And Cadmium Multiple Contaminated Paddy Soil

The development of industry and agriculture not only brings great benefits, but also to the paddy soil has many negative effects, especially in the paddy soil heavy metal and organic pollution is more and more serious. Many experts and scholars in related fields have carried out research on the work of heavy metal pollution, organic pollution and heavy metal, organic compound contaminated soil remediation and comprehensive treatment, etc.. Biomass carbon is a kind of solid material, which has a high degree of aromatic, large specific surface area and porous characteristics, which has a high degree of aromatic, large specific surface area and porous characteristics, which can effectively reduce the activity of heavy metals and organic pollutants in soil and wastewater. This paper is to study the relationship between the input of the biomass carbon and the soil contaminated by lead and cadmium in the paddy soil. Specific results are as follows:By pot experiment, the effects of the whole environment on the whole environment of two sampling points were explored in three treatments, which were treated by fertilization, fertilization and composting, fertilization and composting. The average yield increase of 14.3% in the control group was more than that of the control group, and the application of the increase in the yield of the compost was 8.65%. It is explained that the biomass carbon can be more effective in improving soil nutrient contents and increasing the ion exchange capacity of soil. At the same time, this kind of combination also reduced the increase of soil salinity to a certain extent, which is helpful to the improvement of soil properties, and to promote the production of rice. After adding biological carbon, the pH value of the contaminated soil was improved, and the hydrolysis of Pb and Cd was affected. The Cd, Pb and the absorption of brown rice in paddy soil was significantly related to the absorption of brown rice, and the Cd and Pb contents in brown rice were decreased significantly by Pb. After the application of biomass carbon, soil exchangeable Cd content was decreased by an average of 44.4%, the average Cd content in brown rice decreased by 49.5%, and the average Pb content in soil decreased by 91%, and the Pb content in brown rice decreased by 61.3%.Using field rice experiments, the effects of this kind of biomass carbon on Soil and paddy crops in four different treatments were studied. The following is the specific research results. In terms of reducing the heavy metal to rice plants in migration rate, spraying lime and superphosphate treatment is superior to the control group, the specific values are as follows. Rice in heavy metals decreased values of Pb was 52.0%, Zn was 19.4% and Cd was 43.1%. In rice plants, the contents of Zn and Pb were as follows:root> stem leaf> shell> rice. The migration ability of all kinds of heavy metals was: Cd>Zn>Pb, and the migration of Cd was the strongest. The results showed that the yield of rice increased from 0.59 kg.m-2 to 0.72 kg.m-2, and the content of heavy metals in rice was also decreased, such as Zn, Cd and Pb.