Research On The Effect Of Sludge Biochar In Soil Improvement And Plant Growth

The use of biochar made of sludge for plant growth and soil improvement can solve the problem of sludge outflow,and can also solve the drawbacks of traditional sludge land use methods,and sludge biochar also has the function of adsorbing and solidifying heavy metals,thereby achieving the purpose of reduction,stabilization and resource utilization.The results of planting experiments and physical and chemical properties of loam improved by sludge charcoal showed that the growth of Chinese cabbage in the sludge charcoal group was the best,and the growth of Chinese cabbage in the 10%and 20% improver dry weight group was the best;The application increases the total porosity of the loam,non-capillary porosity,sand content,water-stable large agglomerates,NPK content and organic matter content.Relatively speaking,the addition of sludge charcoal makes the improved loam better.Physical and chemical properties(especially bulk density,salt content,aeration and water permeability,and organic matter content),which is consistent with the results of planting experiments.The experiment of planting soil and soil physicochemical properties improved by sludge charcoal showed that the addition of sludge charcoal did not promote the growth of sandy cabbage,and the growth of Chinese cabbage in sludge composting group and sludge charcoal group did not.Significant difference,compared with the control group,there is no advantage,10% and 20% improver dry weight added amount of cabbage is relatively the best growth;sludge carbon addition is not ideal for the improvement of physical and chemical properties of sandy soil,two The addition of modifiers increases the sand content and reduces the amount of clay and powder.The addition of sludge compost reduces the bulk density and significantly increases the salt content.The addition of sludge charcoal reduced total porosity,capillary porosity,water retention and maximum water content,which is consistent with the results of planting experiments.In short,the addition of sludge charcoal is not ideal for improving sandy soil.The experiment of planting heavy metal nickel contaminated soil by sludge charcoal and the analysis of heavy metal morphology showed that the heavy metal content in pakchoi was not detected.In the improved heavy metal contaminated soil,the unstable state of heavy metal nickel changed to a small trend and stable state.The residual state has a tendency to increase;in addition,the toxic leaching amount of sludge carbon nickel is less than that of dry sludge.In short,sludge charcoal has the function of adsorbing and solidifying heavy metals and alleviating the hazards of heavy metals,and it is more environmentally friendly.