Planting density influence on fibrous root reinforcement of soils
Planting density influence on fibrous root reinforcement of soils
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DOI：
10.1016/j.ecoleng.2009.02.005
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发表时间：
2010-03-01
影响因子：
3.8
通讯作者：
Hallett, P. D.
中科院分区：
文献类型：
--
作者：
Loades, K. W.;Bengough, A. G.;Hallett, P. D.
纤维状根系对土壤的加固作用对于防止土壤侵蚀和退化至关重要，然而其潜在机制却鲜为人知。我们通过在可控温室中以及一项单独的田间研究，对不同种植密度的大麦（Hordeum vulgare）根系对土壤的加固作用进行了研究。在5周时，土壤抗剪强度随种植密度（0 - 950株/平方米）的增加而增加，相较于休耕地（7.5 ± 0.47千帕），强度平均增加了6.7 ± 1.40千帕。在20周时，种植密度的影响较小，根系对强度的贡献平均增加了29%。在温室研究中，根系使抗剪强度平均增加了53%，对于所测试的从0到1130株/平方米的8种种植密度都有积极影响。对根系抗张强度以及剪切面处直径分布的详细测量，使我们能够应用并测试Wu等人[Wu, T.H., Mckinnell, W.P., Swanston, D.N., 1979.阿拉斯加威尔士王子岛树木根系强度与山体滑坡。《加拿大岩土工程杂志》16, 19 - 33]以及Pollen和Simon[Pollen, N., Simon, A., 2005.利用纤维束模型估算河岸植被对河岸稳定性的力学影响。《水资源研究》41]提出的两种现有的根系加固模型。Pollen和Simon[Pollen, N., Simon, A., 2005.利用纤维束模型估算河岸植被对河岸稳定性的力学影响。《水资源研究》41]提出的渐进破坏纤维束模型比Wu等人[Wu, T.H., Mckinnell, W.P., Swanston, D.N., 1979.阿拉斯加威尔士王子岛树木根系强度与山体滑坡。《加拿大岩土工程杂志》16, 19 - 33]的灾难性破坏模型能更好地预测加固效果，但对于20周时接近成熟的田间种植植物，这两种模型都不能很好地描述加固情况。（C）2009 Elsevier B.V.保留所有权利。
Reinforcement of soil by fibrous roots is crucial for preventing soil erosion and degradation, yet the underlying mechanisms are poorly understood. We investigated soil reinforcement by roots of barley (Hordeum vulgare) planted at different densities in a controlled glasshouse and a separate field study. Soil shear strength increased with planting density (0-950 m(-2)) at 5 weeks with an average 6.7 +/- 1.40 kPa increase in strength over the fallow (7.5 +/- 0.47 kPa). At 20 weeks, planting density had less of an effect, with on average a 29% increase in strength contributed by roots. In the glasshouse study, roots increased shear strength by an average of 53%, with a positive effect found for the eight planting densities tested ranging from 0 to 1130 plants/m(2). Detailed measures of root tensile strength, and diameter distributions at the shear plane, allowed us to apply and test two existing root reinforcement models of Wu et al. [Wu, T.H., Mckinnell, W.P., Swanston, D.N., 1979. Strength of tree roots and landslides on Prince-Of-Wales-Island, Alaska. Canadian Geotechnical journal 16,19-33] and Pollen and Sinion [Pollen, N., Simon, A., 2005. Estimating the mechanical effects of riparian vegetation on stream bank stability using a fiber bundle model. Water Resources Research, 41]. A progressive failure Fibre Bundle Model, developed by Pollen and Simon [Pollen, N., Simon, A., 2005. Estimating the mechanical effects of riparian vegetation on stream bank stability using a fiber bundle model. Water Resources Research, 41], predicted reinforcement better than the catastrophic failure model by Wu et al. [Wu, T.H., Mckinnell, W.P., Swanston, D.N., 1979. Strength of tree roots and landslides on Prince-Of-Wales-Island, Alaska. Canadian Geotechnical journal 16, 19-33], but neither described reinforcement well for field-grown plants near maturity at 20 weeks. (C) 2009 Elsevier B.V. All rights reserved.