Abstract:
Objective This study aimed to analyze the species composition and community structure of soil mesofauna arthropods, collembolans and mites under the cultivation of maize tillage and nitrogen application, to provide a reference for suitable tillage methods and fertilizer management in maize farmland in black soil.
Methods A two-factor split-plot design was adopted for maize field in black soil area. Soil tillage was the main factor and nitrogen application was the secondary treatment. There were four treatments in total: rotary tillage without nitrogen (CKN0), rotary tillage with nitrogen (CKN180), strip tillage without nitrogen (STN0) and strip tillage with nitrogen (STN180). Tullgren dry funnel method was used to collembolan and mites in nitrogen application. Changes in soil physical and chemical properties, species composition and community characteristics of mites and collembolans, and their correlation were analyzed and compared under different treatments by community characteristics analysis methods (such as principal component analysis, non-metric multidimensional scaling, etc.).
Results Total of 5427 soil animals were obtained and belonged to 28 families and 41 species. The diversity of collembolan and mite communities was significantly altered by tillage management, specifically, the abundance and biomass of collembolans and mites were significantly higher in strip tillage-managed land than in rotary tillage-managed land. Meanwhile, over 70% of collembolan species and mite families in strip tillage-managed land had an increase in abundance and biomass compared to the rotary tillage-managed land, including Allonychirus songi, Oribellidae sp.1 and Pantelozetes sp.1. Nitrogen application had a non-significant effect on of collembolan and mite communities, while nitrogen application influenced collembolan and mite communities significantly in rotary tillage managed land, resulting in a higher abundance and biomass of collembolan in nitrogen addition land than in the nitrogen control land, but it was opposite for mite. The structural equation model showed that nitrogen application was the only variable that directly affected crop productivity. In addition, the tillage practices had a negative effect on soil properties, and the soil properties had a further negative effect on the diversity of mites, resulting in a positive indirect effect of tillage practices on the diversity of mites.
Conclusion On the one hand, strip tillage increases the food resources of soil animals through straw return, which directly promotes the abundance and biomass growth of collembolans and mites, and indirectly promotes the increase of the diversity of collembolans and mites by increasing soil pH value and organic carbon content. The responding strategies of different collembolans and mites to nitrogen fertilization should be differed.