Effect Of Gasification Slag Compound Fertilizer Application On Soil And Crops

Gasification slag is a solid waste produced by coal slurry entering the gasifier under high temperature and high pressure oxidation in the process of ammonia synthesis in a urine plant.Its massive discharge polluted the air,soil and groundwater,etc.In order to reduce environmental pollution and improve resource utilization,gasification slag was used in industry and agriculture.Flyash,biochar,coal-based and other resources with similar properties were used in agriculture for soil improvement and compound fertilizer production and so on,which could effectively improve crop growth and nutrient utilization.Therefore,using Pakchoi as the experimental material gasification slag was made into compound fertilizer to study the effects of different dosage of gasification slag compound fertilizer on soil nutrients,p H value,organic matter,soil enzyme activity,growth,yield,quality and nutrient absorption and utilization of Pakchoi by pot experiment,and explore the effects of different dosage of gasification slag compound fertilizer on soil and crops,providing technical basis for preparation and application of gasification slag compound fertilizer.The main results were as follows:(1)The contents of soil organic matter,ammonium nitrogen,nitrate nitrogen,available phosphorus and available potassium in different growth stages of Pakchoi could be increased by applying different amounts of gasification slag compound fertilizer.Compared with the treatment of chemical fertilizer(HF),the organic matter and available phosphorus increased by 18.47 % and 20.16 % respectively in the treatment of high dosage gasification slag compound fertilizer(QHZ-high)at maturity stage(45 days).Nitrate nitrogen,available nitrogen and available potassium increased by 12.55 %,40 % and 2.34 %,respectively,under moderate amount of gasification residue compound fertilizer(QHZ-medium).Ammonium nitrogen increased by 5.97 % in low dosage gasification slag compound fertilizer(QHZ-low)treatment.The application of gasification slag compound fertilizer can reduce p H value by0.01～0.23 units compared with that of chemical fertilizer.Among the three kinds of gasification slag compound fertilizer,the soil with QHZ-low treatment had the highest ammonium nitrogen content.The nitrate nitrogen content in QHZ-medium is the highest.QHZ-high the content of organic matter,available phosphorus and available potassium with high,and the p H value is the lowest.(2)The activity of soil enzyme could be improved by applying different amount of gasification slag compound fertilizer.In the mature stage of Pakchoi,compared with HF treatment,urease activity in QHZ-low treatment increased by 11.45 %,and the effect was the most significant.The phosphatase activity of QHZ-medium was increased by 18.96 %,and the effect was the most significant.The urease activity and phosphatase activity of QHZhigh treatment were the highest,and increased by 71.43 % and 283.33 %,respectively,compared with the control.(3)Application of different amount of gasification slag compound fertilizer can promote the growth and nutrient accumulation of Pakchoi.In the mature stage,QHZ-high treatment had the highest plant height,leaf area,SPAD value,fresh weight,dry matter accumulation,nitrogen,phosphorus and potassium accumulation,and the most significant effect among three kinds of gasification slag compound fertilizer treatments.Compared with CK,they increased by 55.39 %,169.40 %,50.98 %,817.66 %,472.80 %,291.63 %,364.90 %and 519.69 %,respectively.(4)Applying different amounts of gasification slag compound fertilizer could improve the quality of Pakchoi.In the mature stage,the contents of VC,soluble protein and crude fiber of QHZ-high treatment increased by 28.08 %,64.25 % and 7.45 % respectively compared with CK.(5)The application of gasification slag compound fertilizer could improve the yield and nutrient utilization efficiency of Pakchoi.In the mature stage of Pakchoi,compared with HF treatment,the yield of QHZ-high was the highest 878.24 g/pot;The yield of QHZ – low increased by 101.29 %,and the effect was the most significant.The utilization rates of N,P and K increased by 7.26 %,4.68 % and 25.93 % respectively,the contribution rates increased by 0.89 %,3.01 % and 3.58 % respectively,the partial productivity increased by 49.82 g/g,155.70 g/g and 83.04 g/g respectively,the agronomic efficiency increased by 114.87 g/g,155.70 g/g and 83.04 g/g respectively.The results showed that the gasification slag compound fertilizer had the greatest effect on the utilization and contribution rate of Pakchoi K,and had the most obvious effect on the partial productivity,agronomic efficiency and physiological efficiency of P.No matter how much the application amount of gasification slag compound fertilizer is,the contents of soil organic matter,nitrate nitrogen,ammonium nitrogen,available nitrogen,available phosphorus,available potassium and the activities of urease and phosphatase can be increased,and the soil p H can be reduced.The high dosage of gasification slag compound fertilizer could promote the growth,increase the SPAD value and the accumulation of nitrogen,phosphorus and potassium,and improve the yield and nutrient utilization efficiency of Pakchoi.Therefore,the gasification slag compound fertilizer has application prospect in agriculture.