Research On Comprehensive Utilization Of Straw And Environmental Remediation Of Black Soil

Straw is a good biological resource.Abandonment or incineration is not only a waste of resources,but also pollutes the environment.In recent years,the control of straw incineration has become increasingly strict,and the state encourages the development of straw comprehensive utilization technology.Soil degradation in the black land is a global crisis,mainly due to the absorption of soil nutrients by continuous cultivation without effective supplementation,as well as soil environmental pollution caused by excessive application of chemical fertilizers.In order to realize the utilization of straw as a resource and solve the problem of soil degradation in black soil,this study prepared straw fermentation fertilizer and selected the test fertilizer through indicators such as the degree of maturity.Through pot experiments,the effects of the types and application rates of straw fermentation fertilizer on the black soil environment and corn growth were studied,and the comprehensive evaluation of the remediation effect of straw fermentation fertilizer on black soil was conducted.The results are as follows:(1)Using corn straw,chicken manure,and cow manure as raw materials,straw fermentation fertilizer was prepared at different ratios.It was found that the fermentation temperature of cow manure straw fermentation fertilizer(1:1)and chicken manure straw fermentation fertilizer(1:1)met the requirements for harmless treatment and had the highest degree of humification,so they were selected as soil remediation materials.(2)The application of straw fermentation fertilizer reduced the soil p H value during the maize growth period,and the straw fermentation fertilizer with high fertilization amount in the mature stage increased the soil p H value,increased the soil organic matter content,was conducive to the accumulation of soil organic matter,increased the soil nutrient content,and the impact effect was related to the fertilization amount and fertilization type.At the seedling stage,the contents of ammonium nitrogen,available phosphorus and available potassium in the soil were increased to a certain extent by each fertilization scheme.During the jointing period,when the fertilization rate of chicken manure-straw fermentation fertilizer and cow manure-straw fermentation fertilizer is 15%,the ammonium nitrogen and available phosphorus content of soil can be significantly increased.When the fertilization rate of the above two straw fermentation fertilizers was 15%,the soil available potassium content was significantly increased compared with the seedling stage.During the ripening period,the soil ammonium nitrogen content increased in each fertilization scheme.(3)The application of straw fermentation fertilizer can improve soil enzyme activity.Soil enzyme activity was affected by the amount of fertilizer applied,and there was a positive correlation between the maturity period and the amount of fertilizer applied.Enzyme activity is also affected by soil environment,among which soil p H and organic matter content are the main influencing factors,and there are also interactions between soil enzymes.(4)The application of straw fermentation fertilizer increased the plant height,stem diameter,and 1000-grain weight of corn to a certain extent,and was significantly positively correlated with the amount of fertilizer applied.Applying straw fermentation fertilizer can significantly increase the plant height and 1000-grain weight of corn,among which,chicken manure straw fermentation fertilizer with a fertilization amount of 15% is the highest.Soil enzyme activity has a significant impact on maize growth.Straw fermentation fertilizer can improve soil environment,regulate soil enzyme activity,and help maize absorb nutrients by affecting soil nutrient content.(5)Based on principal component analysis-cluster analysis,the evaluation model of black soil remediation effect was constructed.The results showed that the application of straw fermentation organic fertilizer could achieve black soil remediation,and the chicken manure-straw fermentation fertilization scheme with a fertilization rate of 15% in the late stage of maize growth had the highest comprehensive score.The main influencing factor of straw fermentation fertilizer on the remediation effect of black soil was the fertilization amount,which increased with the increase of fertilization amount,and chicken manure-straw fermentation fertilizer had a better remediation effect on black soil.