Effects Of Organic Fertilizer Substitution On Physical And Chemical Properties Of Black Soil And Maize Yield

It has a huge cost to the ecological environment that excessive use of fertilizer.There are such as excessive use of fertilizers in farmland and low utilization rate of organic fertilizer resources in China.It is more feasible to implement organic fertilizer instead of chemical fertilizer in a large area,the black soil having a lot of poultry manure,large reserves of organic fertilizer and rich nutrient content.In this study,the typical sticky bottom black soil was used as the test subject and decomposed sheep manure was organic fertilizer.There were 6 treatments,namely,no fertilization treatment(CK)and single application of chemical fertilizer(NPK).Single application of organic fertilizer(OM),organic fertilizer + chemical fertilizer(OM100),organic fertilizer + nitrogen fertilizer nitrogen reduction of 30%(OM70),organic fertilizer + nitrogen fertilizer nitrogen reduction of 50%(OM50).According to field experiments,soil bulk density,field water holding capacity,three comparisons,soil porosity,soil p H,organic matter,alkali nitrogen,available phosphorus,available potassium,total nitrogen,total phosphorus,total potassium,corn yield,etc.were measured and analyzed.Under the condition of replacing organic fertilizer,the effect of organic fertilizer substitution on soil physical and chemical properties and yield.The main results are as follows:(1)Moderate organic fertilizer replacement can reduce soil bulk density.A certain degree alternative fertilizer by organic fertilizer can significantly improve field water capacity.Moderate organic fertilizer treatment can increase soil capillary porosity,significantly increase the soil gas phase ratio and reduce the liquid phase ratio(2)In the short term,the organic matter of organic fertilizer treatments after harvest were lower than that of single application of chemical fertilizer treatment(NPK).This study considered that foreign organic materials entered the soil rich in organic matter,causing positive excitation effect and consuming soil original,because of " positive priming effect".The replacement of organic fertilizer can increase the content of available potassium and total nitrogen in soil.Compared with single application of chemical fertilizer,the effect of improving total phosphorus and total potassium in soil is not obvious.(3)For corn yield,single application of organic fertilizer will result in crop yield reduction in the short term,and moderate organic fertilizer replacement can replace crop yield.(4)On the premise of ensuring that production does not reduce production,economic benefit analysis,organic fertilizer replacement treatment OM70 output ratio is the largest,can better improve the utilization of fertilizer resources,maintain corn production,optimize agricultural resource allocation.Based on the correlation analysis of physical and chemical properties(OM,OM50,OM70,OM100)physicochemical properties and yield,organic matter has significant or extremely significant correlation with soil physical properties,combined with the "positive priming effect" of organic matter,indicating exogenous organic matter.Entry into the soil has a significant or extremely significant effect on soil physical properties.Based on the analysis of principal component comprehensive scores for physical and chemical properties of each treatment,it is indicated that moderate organic fertilizer replacement(OM70,OM50)can improve soil physical and chemical properties,and single application of organic fertilizer(OM)can not shape a good water-gas balance state suitable for plant growth;The linear fitting analysis of the physicochemical properties of some organic fertilizer treatments(OM100,OM70,OM50)showed that the soil physical and chemical properties decreased with the increase of the proportion of organic fertilizer instead of nitrogen fertilizer.Based on the multiple linear regression analysis of the soil nutrient content of each treatment,the moderate organic fertilizer replacement(OM70)can improve the soil nutrient content compared with the single application of chemical fertilizer.The linear fitting analysis of the organic fertilizer replacement treatment nutrient score shows that with organic matter.The increase of fertilizer replacement nitrogen ratio,soil nutrient content increased first and then decreased.(5)Based on the above analysis,this study synthesizes the physical and chemical properties of each treatment and analyzes it.It is considered that the replacement of moderate organic fertilizer can improve soil physical properties and soil nutrient status better than single application of chemical fertilizer and single application of organic fertilizer.Single application of organic fertilizer will cause crop yield reduction in a short period of time.Among them,organic fertilizer instead of nitrogen fertilizer is 30%(OM70),which can promote crop yield increase,improve agricultural resource allocation,and improve nutrient status.