吕 威, 李淑芹, 李法虎, 雷廷武. 聚丙烯酰胺对凹凸型坡土壤侵蚀影响的室内试验[J]. 农业工程学报, 2016, 32(10): 122-128. DOI: 10.11975/j.issn.1002-6819.2016.10.017
    引用本文: 吕 威, 李淑芹, 李法虎, 雷廷武. 聚丙烯酰胺对凹凸型坡土壤侵蚀影响的室内试验[J]. 农业工程学报, 2016, 32(10): 122-128. DOI: 10.11975/j.issn.1002-6819.2016.10.017
    Lü Wei, Li Shuqin, Li Fahu, Lei Tingwu. Laboratory study on soil erosion of loess convex and concave slopes with application of polyacrylamide[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(10): 122-128. DOI: 10.11975/j.issn.1002-6819.2016.10.017
    Citation: Lü Wei, Li Shuqin, Li Fahu, Lei Tingwu. Laboratory study on soil erosion of loess convex and concave slopes with application of polyacrylamide[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(10): 122-128. DOI: 10.11975/j.issn.1002-6819.2016.10.017

    聚丙烯酰胺对凹凸型坡土壤侵蚀影响的室内试验

    Laboratory study on soil erosion of loess convex and concave slopes with application of polyacrylamide

    • 摘要: 通过室内人工模拟降雨试验,研究了聚丙烯酰胺(polyacrylamide,PAM)施用量(0、0.5、1.0和2.0 g/m2)对凸型坡(上、下坡坡度分别为5°、10°、15°和20°、25°)和凹型坡(上、下坡坡度分别为20°、25°和5°、10°、15°)土壤侵蚀规律的影响。结果显示,无PAM应用时,凹型坡或小坡度凸型坡(上坡坡度为5°)径流含沙量随降雨历时逐渐减小,而大坡度凸型坡(上坡坡度≥10°)径流含沙量在降雨过程中会急剧增大。凸型坡平均土壤流失量是凹型坡的8.4倍。PAM应用显著增大了凹型坡和小坡度凸型坡径流含沙量和土壤流失量(P<0.05),但减小了大坡度凸型坡土壤流失量。PAM应用后,土壤流失量与坡度大小无明显关系,此时凸型坡平均土壤流失量为凹型坡的1.2倍。在生产实践中PAM可用于控制较陡(≥10°)凸型坡的土壤流失。

       

      Abstract: The effects of polyacrylamide(PAM) application rate on composite slope were carried out under simulated rainfall condition in the laboratory. The composite slope included convex and concave slopes. The upslope and down slope gradients of convex slope respectively were 5°, 10°, 15° and 20°, 25°, and those of concave slope were 20°, 25° and 5°, 10°, 15°. Polyacrylamide application rates were 0(control), 5, 10, and 20 kg/hm2. Total treatment numbers were 48. Results showed that under no PAM application, sediment concentration in runoff on concave slope or the convex slope with a small upslope gradient (5°) was decreasing gradually with rainfall duration, but the sediment concentration in runoff on the convex slope with a big upslope gradient(≥10°) increased sharply at some time during rainfall process because of rill erosion occurrence. The time that rill erosion occurred usually was within 8-10 min. after rainfall began, and it was shortened with the increased upslope gradient for the convex slope with gradient greater than 10°. The possibility of rill erosion occurrence on convex slope was higher than on concave slope under no PAM application. Soil mass loss increased with the increase of slope gradient, and the averaged soil mass loss from all convex slope treatments was 7.4 times greater than that from concave slope treatments. Generally, PAM application significantly increased sediment concentration in runoff and soil mass loss from concave slope or the convex slope with the small upslope gradient of 5° (P<0.05). Polyacrylamide application played a remarkable control role on rill erosion occurrence and no obvious rill erosion occurred after its application, consequently PAM application resulted in the decrease of soil mass loss from the convex slope with the gradient greater than 10°. After PAM application, the combination of different slope gradients did not obviously affect soil mass loss for convex slope and concave slope. When PAM application rates were 5, 10 and 20 kg/hm2, the averaged soil mass loss was(1.61±0.30), (2.27±0.77), and(1.83±0.57) kg for convex slopes and(1.09±0.38), (1.82±0.59), and (1.87±0.49) kg for concave slopes, respectively, and the averaged soil mass loss from convex slopes for all PAM application rate treatments was 20% greater than that from concave slopes. Polyacrylamide can be used to control soil loss from convex slope with an upslope gradient bigger than 10° in production practice.

       

    /

    返回文章
    返回