为研究土壤水力参数的空间分布特征，并揭示相关影响因素，以江汉平原典型近江农业区为研究单元，采集不同类型农用地的浅层（0~40 cm）原状和扰动土样，测定其水力参数和相关理化性质，揭示各水力参数及相关理化性质的空间分布特征，比较不同样地各参数和性质的差异，并分析相关影响因素。结果表明：研究区土壤各基本理化性质（土壤机械组成、有机质含量、容重、直径>0.1 mm和>0.3 mm大孔隙含量）和水力参数（饱和含水量（θ_s）、残余含水量（θ_r）、水分特征曲线拟合参数ɑ和n、田间持水量（θ_f）、凋萎系数（θ_w）和最大有效水含量（θ_AW））均具有明显的空间异质性；近江区土壤机械组成、有机质含量、容重等部分理化性质与距江远近具有较强的空间相关性；直径>0.1 mm和>0.3 mm大孔隙含量，θ_s和θ_r，以及θ_f和θ_AW的空间分布特征相似。不同样地的有机质含量、容重和直径>0.3 mm大孔隙含量具有显著差异。土壤理化性质的差异显著影响了K_s和水分特征曲线参数（特别是θ_s和n）。不同农用地土壤的水力性质也存在差异，稻田和旱地的入渗性能较好，表现为最高的中位K_s（18.7 cm/h），其他样地的K_s差异较小（9.2~10.5 cm/h）。菜地的持水能力最强，表现为较高的θ_f（0.46 cm³/cm³）、θ_w（0.07 cm³/cm³）和θ_AW（0.39 cm³/cm³），其他样地的土壤水力参数差异较小。河流冲积物的分布显著影响了研究区农用地的土壤机械组成，对容重和有机质含量分布也有一些影响；而人类耕作活动可以显著改变土壤的有机质含量、大孔隙含量和容重，但对机械组成影响较小；自然要素和人为活动的共同作用影响了各水力参数的分布特征。在近江农业区开展土壤调查和农业生产规划时，需要考虑河流冲积物的分布特征。

To study the spatial distribution characteristics of soil hydraulic parameters and their influencing factors, the typical agricultural area near the Yangtze River in Jianghan Plain was taken as the study unit, the undisturbed and disturbed soil samples were collected from shallow layers (0-40 cm) of different farmland types, and the hydraulic parameters and related physiochemical properties were determined, then the spatial distribution characteristics of hydraulic parameters and their relation with physiochemical properties were studied and compared. The results showed that the basic physicochemical properties of soil (soil mechanical composition, organic matter content, bulk density, diameter > 0.1 mm and > 0.3 mm large pore content) and hydraulic parameters (saturated water content (θ_s), residual water content (θ_r), water characteristic curve fitting parameters ɑ and n, field water holding capacity (θ_f), wilting soil water content (θ_w) and maximum effective water content (θ_AW) in the study area had apparent spatial heterogeneity. The physical and chemical properties of soil mechanical composition, organic matter content, and bulk density were strongly correlated with the distance from the river. The spatial distribution characteristics of diameter > 0.1 mm and > 0.3 mm large pore content, θ_s and θ_r, θ_f and θ_AW were similar. Organic matter content, bulk density and macroporosity with a diameter > 0.3 mm significantly differed among the different land types. Differences in soil physiochemical properties significantly affected K_s and moisture profile parameters (especially θ_s and n). The paddy and dry fields had better infiltration performance with the highest median K_s (18.7 cm/h), and the K_s of other fields had little difference (9.2-10.5 cm/h). The vegetable field had the strongest water-holding capacity with higher θ_f (0.46 cm³/cm³), θ_w (0.07 cm³/cm³) and θ_AW (0.39 cm³/cm³), and soil hydraulic parameters of other plots had little difference. The distribution of alluvial deposits significantly affected soil mechanical composition and had some influences on the distribution of bulk density and organic matter. Human farming activities significantly changed soil organic matter content, macropore porosity and bulk density, but little influenced soil mechanical composition. The distribution characteristics of hydraulic parameters were affected by the combination of natural factors and human activities. In conclusion, the distribution characteristics of alluvial deposits need to be considered for soil surveys and agricultural production planning in agricultural areas near the river.

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国家自然科学基金区域创新发展联合基金项目（U21A2039）和中央高校基本科研业务费（CCNU22JC013）资助。