摘要: |
摘 要:【目的】探究黄腐酸钾对黑垆土水分运移、土壤孔隙和团聚体分布的影响。【方法】通过室内试验,向黑垆土中施加不同质量配比(0 %、0.1 %、0.5 %和1 %)的黄腐酸钾,得到对土壤结构改良效果的最佳黄腐酸钾施量。【结果】①用含1 %黄腐酸钾处理后的土样效果是最优的,土壤累积入渗量、入渗率(90 min)、稳渗率和湿润锋运移距离分别增加了43.96 %、182.5 %、47.06 %和28.41 %。②3种入渗模型参数拟合结果显示,Kostiakov公式中经验系数从1.648 7减小至0.901 3,经验指数从0.478 1增加至0.537 5。Philip公式中稳渗率在0.002 0到 0.003 1的范围内,吸渗率在0.956 2到1.004 2范围波动。改进后Kostiakov公式中,稳定入渗率从0.012 6增加至0.084 6。③掺加含1 %黄腐酸钾的土样对土壤孔隙度的影响最大,土壤总孔隙度和土壤通气孔隙度分别增加了2.65 %和64.29 %,土壤毛管孔隙度降低了17.00 %。同时土样中掺入黄腐酸钾的质量配比越大,在单位体积上相较于对照组,土壤容重减小了2.99 %。④随着培养时间增长,粒径大于0.25 mm团聚体量 显著增加,同时粒径<0.045 mm团聚体量逐渐减少。平均几何直径与黄腐酸钾施量之间呈现正相关关系,而不稳定团粒指数和土壤可蚀性因子随黄腐酸钾施量增加呈现负相关,分形维数随着时间与黄腐酸钾施量的增大呈现减小趋势。【结论】施加质量配比为1 %黄腐酸钾对黑垆土结构改良效果是最佳的,该研究成果为揭示不同施量黄腐酸钾对黑垆土水分运移和结构改良效果方面提供参考。 |
关键词: 黄腐酸钾;水分运移;土壤孔性;水稳性团聚体;土壤结构 |
DOI: |
分类号:S156.2 |
基金项目:西北旱区生态水利工程国家重点实验室科研项目(2016ZZKT-9);陕西省教育厅重点实验室科研计划项目(17JS096) |
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Effect of Applying Potassium Fulvic Acid on Structure of Dark Loessial Soil |
Zhang lu1,2,3, Wu Junhu1,2,3
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1.xi'2.'3.an university of technology
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Abstract: |
By adding potassium fulvic acid with different application to the dark loessial soil, combined with laboratory experiments, the effects of potassium fulvic acid on the water transport, soil pores and aggregate composition of the dark loessial soil were explored. The results showed that: (1) For the soil sample treated with 1% potassium fulvic acid, the cumulative infiltration rate, infiltration rate (90min), stable infiltration rate and wet front migration distance increased by 43.96% ,182.5%, 47.06% and 28.41% respectively. (2) The fitting results of the three infiltration model parameters show that the empirical coefficient in the Kostiakov Formula attenuates from 1.6487 to 0.9013, and the empirical index increases from 0.4781 to 0.5375. In the Philip Formula, the stable permeability is in the range of 0.0020 to 0.0031, and the absorption rate fluctuates in the range of 0.9562 to 1.0042. In the improved Kostiakov Formula, the stable infiltration rate increased from 0.0126 to 0.0846. (3) The soil sample mixed with 1% potassium fulvic acid increased the aeration porosity of the soil by 64.29%, the capillary porosity of the soil decreased by 17.00%, and the total soil porosity increased by 2.65%. At the same time, the larger the mass ratio of potassium fulvic acid mixed in the soil sample, the soil density decreased by 2.99% compared to the control group in terms of unit volume. (4) With the increase of the culture time, the content of agglomerates with a particle size greater than 0.25mm increased significantly, while the content of agglomerates with a particle size less than 0.045mm gradually decreased. There is a positive correlation between the mean geometric diameter and the potassium fulvic acid application rate, while the unstable aggregate index and soil erodibility factors are negatively correlated with the increase of the potassium fulvic acid application rate, with potassium fulvic acid and time incresse the fractal dimension has a positive correlation. The research results provide a reference for revealing the mechanism of action of different application rates of potassium fulvic acid on improving the structure of dark loessial soil. |
Key words: Potassium fulvic acid; moisture transport; soil porosity; water-stable soil aggregate; soil structure |