Effects of Long-Term Straw Returning on Soil Aggregates and Organic Carbon in Tobacco-Growing Soil
[Objective]This study aims to explore the effects of long-term straw returning in the Central Henan tobacco-growing area on the distribution and stability of soil aggregates and the impact on organic carbon[Methods]From 2021 to 2022,in the long-term fertilization experimental fields of Zhengzhou Science and Education Park,Henan Agricultural University,the agronomic traits of tobacco plants and soil physicochemical indicators were measured under three treatments:no fertilizer(NF),chemical fertilizer(NPK),and chemical fertilizer plus wheat straw return(NPKS).[Results](1)After 30 days of transplanting,the NPKS treatment significantly increased plant height,maximum leaf length,number of effective leaves,and maximum leaf area compared with the NF and NPK treatments.(2)After 90 days of transplanting,NPKS treatment significantly increased the content of organic matter,alkali-hydrolyzed nitrogen,available phosphorus,and available potassium in the surface soil(0-20 cm)compared with the NF and NPK treatments.(3)After 90 days of transplanting,compared with NF and NPK treatments,NPKS treatment significantly increased the content of macro-aggregates and water-stable macro and large aggregates in both surface and subsurface(20-40 cm)soils,significantly reducing the content of micro-aggregates,while also significantly improving the stability of mechanical and water-stable aggregates.(4)Long-term straw returning increased the organic carbon content in surface and subsurface soils,with the main functional groups of soil organic carbon being phenols,aromatics,olefins,polysaccharides,and carbohydrates.NPKS treatment significantly increased the content of aromatic,olefinic,and carbohydrate functional groups in surface soil compared to NPK treatment,with no significant difference in the organic carbon functional group content in subsurface soil among treatments.(5)After 90 days of transplanting,the impact of alkali-hydrolyzed nitrogen and available potassium on the formation of soil large aggregates and the improvement of aggregate stability was stronger than that of organic carbon.[Conclusion]Long-term straw returning not only promotes the growth and development of tobacco plants but also enhances the stability of soil aggregates.
万方数据
维普
