长期施用不同肥料对春玉米土壤锌锰形态的影响OA

To study the effects of different long-term fertilization measures on soil physical and chemical properties,total Zn,total Mn,available Zn,available Mn,and the contents of various forms of Zinc(Zn)and Manganese(Mn),a 32-year long-term field experiment from 1992 to 2023 was conducted.There were 9 treatments:a control treatment without fertilization(N0P0M0),four single chemical fertilizers treatments(N1P1M0,N2P2M0,N3P3M0,N4P4M0),three organic-inorganic combined fertilization treatments(N2P1M1,N3P2M3,N4P2M2),and a high organic fertilization treatment without chemical fertilizer(N0P0M6).Through redundancy analysis and path analysis of soil total Zn,total Mn,available Zn,available Mn and soil environmental factors,the effects of long-term different fertilization on the forms and biological availability of soil Zn and Mn were explored.The results showed that compared with the non-fertilization treatment,long-term different fertilization significantly increased soil organic matter,total nitrogen,available phosphorus,available potassium,cation exchange capacity and nitrate nitrogen content,and significantly reduced soil pH.Compared with the non-fertilization treatment,the sole application of chemical fertilizer(except for the N4P4M0 treatment)significantly reduced the total Zn content in the soil,while the N2P2M0 and N3P3M0 treatments significantly increased the total Mn content,and there was no significant change in the soil available Zn and Mn content.Organic-inorganic combination application and single application of high-quantity organic fertilizer significantly enhanced the total Zn,total Mn,available Zn and available Mn content in the soil.Among the organic-inorganic combination application treatments,the N3P2M3 treatment had the best effect,increasing by 7.0％,4.8％,447.6％and 43.6％,respectively.Long-term different fertilization treatments could reduce the content of mineral Zn and Mn,and increase the content of other forms of Zn and Mn.And all of these showed that the single application of high amount of organic fertilizer had a better effect than the organic-inorganic combined application and the single application of chemical fertilizer.Path analysis indicated that the main source of available Zn in the soil was oxide-bound Zn,exchangeable Mn was the main source of available Mn in the soil.Redundancy analysis revealed that soil available phosphorus explained 40.50％of the variance variation of total Zn and total Mn in the soil,total nitrogen and available phosphorus explained 92.2％and 1.8％of the variance variation of available Zn and Mn in the soil respectively,and the results were significant.In conclusion,long-term combined application of organic and inorganic fertilizers increased soil organic matter,total nitrogen,available phosphorus,available potassium,cation exchange capacity and nitrate nitrogen content,significantly reduced soil pH,significantly increased soil total Zn,total Mn,available Zn and available Mn contents,promoted the transformation of Zn and Mn from mineral forms to other forms in the soil,thereby enhancing the biological availability of Zn and Mn elements in the soil.The results of this study provided a theoretical basis for improving the biological availability of Zn and Mn in the soil and optimizing fertilization measures.