Effects Of Continuous Combined Application Of Organic And Inorganic Fertilizers On Soil Fertility And Crop Yield Of Yellow Cinnamon Soil

The yellow cinnamon soil is one of the main soil types in the dry farming area of China.It has high production potential,superior water and heat conditions,and strong fertilizer conservation.However,the yellow cinnamon soil is sticky,compact in structure,with farming obstacles and unstable crop yield.Therefore,it is of great significance to improve the fertility of the yellow cinnamon soil.In this study,based on the platform of field experiment,the effects of continuous organic-inorganic combined application on small yield and soil fertility were monitored,and the best fertilization method was selected to guide scientific fertilization.The main results are as follows1.Continuous application of organic and inorganic fertilizer can significantly affect the yield and components of wheat and maize.Compared with CK,fertilization can significantly increase the number of grains per spike and increase crop yield.Compared with NPK treatment,NPKS treatment,NPKM treatment and NPKSM treatment significantly increased the yield of wheat and maize.Among them,NPKM treatment had the best yield increasing effect,and grain number per spike also increased significantly.Wheat yield increased by 7.05%and grain number per spike increased by 11.19%;The yield of maize increased by 11.25%and the number of grains per ear increased by 19.94%.2.Continuous application of organic and inorganic fertilizer had effects on nitrogen accumulation and nitrogen use efficiency of wheat and maize.Compared with NPK treatment,other organic and inorganic treatments significantly increased nitrogen accumulation in stems.leaves and grains of wheat plants,and improved nitrogen use efficiency.The accumulation of nitrogen in grain was greater than that in stem and leaf.and that in maize was greater than that in wheat.Among them,NPKM treatment had the highest nitrogen accumulation,which increased by 20.23%,28.89%and 14.98%in wheat.33.46%,22.57%and 14.78%in maize,15.09%and 13.67%in wheat and maize,respectively.The nitrogen use efficiency of wheat was higher than that of corn,and th real use efficiency was higher than that of corn.3.Continuous application of organic and inorganic fertilizer can affect the change of soil physical and chemical properties.The results showed that the contents of availabl phosphorus,available potassium and organic matter increased significantly unde long-term different organic fertilization methods,but the changes of soil pH,tota nitrogen and Alkali hydrolyzed nitrogen were not significant,and the soil bulk densit,decreased,which promoted the formation of soil micro aggregate structure to larg aggregate structure and improved the stability.NPKM treatment increased the contents o available phosphorus,available potassium and organic matter by 23.54%,19.17%an 19.17%,respectively 04%,the effect is remarkable.4.Continuous application of organic and inorganic fertilizer also affected soil nitrogen balance under wheat maize annual rotation system.Compared with NPK treatment,different organic replacement fertilization methods can reduce nitrogen surplus to a certain extent.Chemical fertilizer and straw,chemical fertilizer and manure,and combined application of chemical fertilizer and straw and manure can reduce nitrogen loss,improve crop nitrogen absorption capacity and reduce nitrogen surplus.The total surplus of two years can be reduced by 92～138 kg/ha.Compared with NPK treatment,NPKM had the least soil surplus,followed by NPKS or NPKSM.