The on-going and extensive use of neonicotinoids occur in orchards. However, it is still unknown whether and how orchard management affects soil properties, especially the contents and structure of soil organic matter during orchard development, and their further influences on neonicotinoid persistence. Here, surface soil samples were collected from the citrus orchards with different cultivation ages (1, 10, 14, and 20 years), and their physicochemical properties were determined. Changes in the chemical structure of soil organic matter (SOM) were furtherly examined using solid-state CP/TOSS ¹³C NMR. Then, the sorption isotherms of imidacloprid in these soils were investigated. The sorption coefficient (K_d) of imidacloprid at C_e of 0.05 mg/L in the orchard soils increased by 19.4–23.3%, along a 20-year chronosequence of cultivation, which should be mainly ascribed to the increase of SOM. However, the organic carbon-normalized sorption coefficient (K_oc, sorption per unit mass of OM) of imidacloprid declined with increasing cultivation ages. Moreover, the polar and aliphatic domains of SOM had a significantly positive relation to the K_oc of imidacloprid, suggesting its key role in governing imidacloprid sorption. The results highlighted that reasonable management measures could be adopted to control the occurrence and fate of neonicotinoids in soils, mainly by affecting the content and quality of SOM.

新烟碱类的持续和广泛使用发生在果园中。然而，果园管理是否以及如何影响土壤性质，特别是果园发育过程中土壤有机质的含量和结构，以及它们对新烟碱类持久性的进一步影响仍是未知的。在这里，从不同栽培年限（1、10、14 和 20 年）的柑橘园收集表层土壤样品，并测定它们的理化性质。使用固态 CP/TOSS ¹³ C NMR进一步检查了土壤有机质 (SOM) 化学结构的变化。然后，研究了吡虫啉在这些土壤中的吸附等温线。吡虫啉在C _e处的吸附系数( K _d )果园土壤中 0.05 mg/L 的增加 19.4-23.3%，随着 20 年的栽培时间顺序，这应该主要归因于 SOM 的增加。然而，吡虫啉的有机碳归一化吸附系数（K _oc，每单位质量 OM 的吸附量）随着栽培年龄的增加而下降。此外，SOM 的极性和脂肪族结构域与吡虫啉的K _oc呈显着正相关，表明其在控制吡虫啉吸附中的关键作用。结果表明，可以采取合理的管理措施来控制土壤中新烟碱类物质的发生和归宿，主要是通过影响 SOM 的含量和质量。