高级检索

    冻融期棉秆隔层对土壤水热盐变化过程的影响

    Effects of a cotton stalk interlayer on soil water, heat, and salt transport processes during the freeze-thaw period

    • 摘要:背景】南疆地区冬季漫长寒冷,土壤经历较长的冻结期,该期间土壤水热盐三者变化过程复杂,不仅影响土壤结构,更对春季融冻后的土壤墒情及播种环境产生影响。【方法】为探究棉秆隔层方式对南疆地区冻融条件下土壤水热盐变化过程的影响,设置棉秆表层覆盖、30cm埋深与无添加3种方式以及2种冬灌定额(1800 m3/hm²与2400 m3/hm²)试验条件,研究冻融期土壤水热盐特征及物理性质的变化。【结果】结果表明:棉秆表层覆盖能提高冻融过程中的土壤含水率与温度,在0~10cm土层平均含水率比无添加提高27.62%,地表平均温度比无添加提高0.75℃,冬灌定额越高土壤冻融期平均温度越高。在0~5cm土层棉秆表层覆盖与30cm埋深含盐量分别为无添加的42.38%和75.69%,冬灌定额对土壤盐分影响不显著(P>0.05)。在0~10cm土层,棉秆表层覆盖与30cm埋深的土壤容重比不添加提高3.37%和0.69%,孔隙度降低2.14%和0.56%,饱和导水率降低了12.13%和2.43%,棉秆表层覆盖可以改善土壤固液气三相比。冬灌定额为2400 m3/hm²的土壤优先流发育更好,棉秆隔层会抑制优先流的发育。【结论】综上可知,棉秆隔层可以抑制土壤积盐,减弱冻融对土壤物理性质与结构的影响,且棉秆表层覆盖作用更明显。该研究为干旱盐渍土地区棉秆资源化利用、农业高效生产等提供理论支撑和应用支持。

       

      Abstract: Background The southern Xinjiang region experiences long and cold winters, with soil undergoing extended freezing periods. During this time, the interrelated dynamics of soil moisture, temperature, and salinity are complex. These processes not only influence soil structure but also significantly affect soil moisture conditions and the sowing environment after the spring thaw. Methods To investigate the effects of cotton stalk interlayer methods on soil moisture, temperature, and salinity dynamics under freeze-thaw conditions in southern Xinjiang, three treatments were established: surface coverage with cotton stalks, burial at 30 cm depth, and a control group with no addition. Two winter irrigation quotas (1800 m³/hm² and 2400 m³/hm²) were applied under experimental conditions to study the changes in soil moisture, temperature, salinity characteristics, and physical properties during the freeze-thaw period. Results Surface coverage with cotton stalks increased soil moisture content and temperature during the freeze-thaw process. The average moisture content in the 0–10 cm soil layer was 27.62% higher compared to the control group without cotton stalk addition, while the average surface temperature increased by 0.75°C. Higher winter irrigation quotas resulted in higher average soil temperatures during the freeze-thaw period. In the 0–5 cm soil layer, the salt content under surface coverage and 30 cm burial treatments was 42.38% and 75.69% of that in the control group, respectively. Winter irrigation quota had no significant effect on soil salinity (P > 0.05). In the 0–10 cm soil layer, soil bulk density under surface coverage and 30 cm burial increased by 3.37% and 0.69%, respectively, compared to the control. Porosity decreased by 2.14% and 0.56%, and saturated hydraulic conductivity decreased by 12.13% and 2.43%. Surface coverage with cotton stalks improved the ratio of solid, liquid, and gas phases in the soil. Soil under a winter irrigation quota of 2400 m³/hm² exhibited better development of preferential flow, while the cotton stalk interlayer suppressed the development of preferential flow. Conclusions The cotton stalk interlayer can mitigate soil salt accumulation and reduce the impact of freeze-thaw cycles on soil physical properties and structure, with surface coverage showing more pronounced effects. This study provides both theoretical support and practical applications for the utilization of cotton stalk resources and the promotion of efficient agricultural production in arid saline-alkali regions.

       

    /

    返回文章
    返回