土壤进气值和发泡点测定方法的研究

Measurement of air entry value and bubbling point of soils

应用土壤电导率与基模吸力的关系,判断和测定了土壤的进气值,采用改进后的砂型漏斗装置测定了土壤的发泡点。对脱水过程中3个不同剖面层次土壤进气值和发泡点的测定结果表明,耕作表层(A p)土壤的进气值和发泡点分别为1.343和5.880 kPa;淋溶淀积过渡层(AB)土壤的进气值和发泡点分别为2.597和4.116kPa;埋藏表层(A b)土壤的进气值和发泡点分别为0.451和6.076 kPa。由此可见,土壤的进气值与发泡点的数值明显不同,进气值与发泡点是2个不同的概念。

Relationship between soil electric conductivity and soil matric suction was used to estimate soil air entry value. Sand mold funnel apparatus provided in this paper was identified as the method for the measurement of soil bubbling point. Air entry value and bubbling point of three profile layers during desorption were measured：Air entry value of Ap horizon was 1. 343 kPa,the bubbling point 5. 880 kPa. Air entry value and bubbling point of AB horizon were 2. 597 kPa and 4. 116 kPa respectively. Air entry value and bubbling point of Ab horizon were 0. 451 kPa and 6. 076 kPa respectively. The measured results show that the air entry value and bubbling point are two concepts with different values.