Effects Of Maize And Soybean Intercropping On Soil Quality And Surface Arthropods

Intensive agricultural production and large-scale single planting have significantly increased grain yield,but they can neither regulate themselves nor maintain themselves,thus breaking the normal succession of the natural ecosystem.In order to maintain the operation of this system,it is necessary to constantly increase the input of external pesticides and fertilizers.With the continuous intensification,the environmental problems brought by the intensification have gradually emerged,and the biodiversity and ecological balance have been destroyed and soil quality has declined.Crop diversity cultivation can use different crops to absorb and utilize the characteristics of different nutrients in the soil to balance the soil nutrients.In this experiment,two treatment points were taken for maize and soybean under the wide stripe planting mode,and one treatment point was taken at the junction to explore the effects of wide stripe planting of maize and soybean on soil quality and soil surface arthropods.The main results are as follows:?1?The soil was extracted from corn and soybean soil and the soil p H,organic matter content,soil water content,NH₄⁺-N,NO₃^--N,total nitrogen,total phosphorus and available phosphorus content were determined.At the end of growth period,there were no significant differences in p H,organic matter content,soil water content,NH₄⁺-N,NO₃^--N,total nitrogen,total phosphorus and available phosphorus content?P>0.05?;The soil NO₃^--N content at the five treatment points was significantly different?P<0.05?,and the soil NO₃^--N content in corn was significantly higher than that in soybean soil.In the wide seeding experiment of corn and soybean,soybean reduced the absorption of soil nitrate nitrogen to meet the demand of corn for nitrate nitrogen in the system.At the same time,the reduced nitrate nitrogen did not affect the normal growth of soybean.It could also reduce the application of nitrogen fertilizer,reduce the large amount of soil nitrate nitrogen residue,and reduce the risk of nitrate leaching.?2?Identification and classification of surface arthropods caught by trap method in corn and soybean fields.The effects of wide strip planting of maize and soybean on soil surface arthro pods were analyzed.Longitudinal comparison of the whole growth period of soybean fields arthropod diversity index is higher than corn field arthropod diversity index,but both index due to the outside world are mutated fell sharply,compared to the border processing point,at the junction of relative outside conditions change diversity index fell quite gentle,finally achieve uniform.It indicates that the surface arthropod community formed at the junction is more buffering than that in the field of common corn and soybean,and it changes slowly in response to the stimulation of external conditions.The analysis of the dominant concentration index shows that the dominant concentration index at the junction increases steadily with the sampling time.Compared with soybean and corn fields,the dominant concentration index at the junction changed more smoothly over time,indicating that the surface arthropod community at the junction was more stable than that in soybean and corn fields.The dynamic changes of arthropod community similarity index over time were obtained by parewise comparison of two adjacent treatment points.During the growth period,the similarity index of soil arthropod communities of soybean and corn experienced a sharp decline,among which the surface arthropod communities of corn were particularly serious.By contrast,the similarity index of junction communities changed steadily without sharp fluctuation.The results showed that wide seeding planting of maize and soybean could improve the stability of arthropod community on the soil surface,which was consistent with the results of other indexes.?3?RDA sequencing was used to analyze the correlation between the community characteristics index of farmland arthropod and soil physical and chemical factors in the wide range of maize and soybean seeding plots.The results showed that the decrease of soil nitrate nitrogen content could reduce the number of dominant species of surface arthropods,and increase the richness index,diversity index and evenness index of surface arthropods.The improvement of these characteristic indexes strengthened the community stability and improved the community's ability to resist external disturbance.