三峡库区紫色土坡耕地草本植物根系固结地埂的土力学机制

发布时间：2018-12-09 11:31

【摘要】：为揭示三峡库区紫色土坡耕地草本植物根系对地埂土壤固结作用的土力学机制,选取库区3种草本地埂植物为研究对象,对3种地埂植物根系的分布特征及抗拉性能进行研究,并分析3种地埂土壤的抗冲性和抗剪强度。研究结果表明,紫花苜蓿、蓑草、桂牧一号的根系总生物量分别为(79.37±1.26),(97.99±1.66),(71.76±1.96)g/m~2,紫花苜蓿根系在0—10cm土层分布最多,蓑草主要根系分布深度集中在10—20cm,桂牧一号根系分布在0—30cm土层深度范围内呈现出递增的趋势,在30—40cm土层深度根系含量不到10%。3种草本地埂植物根系的平均抗拉力为桂牧一号(7.93N)蓑草(6.03N)紫花苜蓿(5.40N),3种地埂植物根系单根抗拉力与根径呈幂函数关系,蓑草地埂植物根系的单根抗拉力与根径的相关性最高。3种地埂植物根系的抗拉强度表现为蓑草根系(45.91MPa)紫花苜蓿根系(19.68 MPa)桂牧一号根系(15.28 MPa)。3种不同草本地埂植物根系间的抗拉力和抗拉强度差异达到显著水平(P0.05)。3种植物地埂土壤的抗冲性变化为蓑草地埂(85.28L/(min·g))紫花苜蓿(69.47L/(min·g))桂牧一号(60.86L/(min·g)),蓑草地埂土壤的抗冲性与紫花苜蓿和桂牧一号间存在显著差异(P0.05)。3种草本植物地埂土壤的抗剪强度顺序为蓑草地埂(115.49kPa)紫花苜蓿(91.73kPa)桂牧一号(75.14kPa)。结果表明,蓑草地埂在三峡库区具有较好的固埂防蚀效果,在三峡库区坡耕地固结地埂土壤中发挥重要作用。三峡库区草本植物固结地埂可为三峡库区坡耕地整治提供新思路。
[Abstract]:In order to reveal the soil mechanics mechanism of herbaceous plant root system on terrace soil consolidation in the three Gorges Reservoir area, three kinds of herbaceous terrace plants were selected as the research objects, and the distribution characteristics and tensile properties of three kinds of terrace plants were studied. The impact resistance and shear strength of three kinds of terrace soils were analyzed. The results showed that the total root biomass of alfalfa, coir and Gui Mu No.1 was (79.37 卤1.26), (97.99 卤1.66), (71.76 卤1.96) g / m-2, respectively, and the root system of alfalfa was the most distributed in 0-10cm soil layer. The distribution depth of main root system was 10-20 cm, and the root distribution of No. 1 of Gui Mu showed an increasing trend in the depth of 0-30cm soil layer. The average tensile resistance of the roots of less than 10.3 species of herbaceous ridge plants in the 30-40cm soil layer was as follows: No. 1 (7.93 N) of Guimu (7.93 N) and (6.03 N) of alfalfa (5.40 N). The relationship between root tensile strength and root diameter was power function. The relationship between single root tensile resistance and root diameter was the highest in the roots of the terrace of coir. The tensile strength of the roots of the three terrace plants was as follows: 45.91MPa (19.68 MPa) and Gui Mu No. 1 (1515). The difference of tensile strength and tensile strength among the roots of three different herbaceous plants reached a significant level (P0.05). Alfalfa (69.47L/ (min g) Guimu 1) (60.86L/ (min g),) There was a significant difference between the impact resistance of the soil on the ridge of coir (P 0.05) and that of alfalfa and Guimu No.1 (P0.05). The order of shear strength of the three herbaceous land ridges was: 115.49kPa, 91.73kPa, 91.73kPa, Cinnamon. 75.14kPa. The results show that the ridge of cod grass has a good effect on the prevention of erosion in the three Gorges reservoir area and plays an important role in the consolidation of the ridge soil of sloping farmland in the three Gorges Reservoir area. The consolidation of the terrace of herbaceous plants in the three Gorges Reservoir area can provide a new idea for the regulation of sloping farmland in the three Gorges Reservoir area.
【作者单位】：中国科学院水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室;
【基金】：中国科学院科技服务网络(STS)项目(KFJ-SW-STS-175,KFJ-EW-STS-008) 国家自然科学基金项目(41671286) 国家重点研发计划项目(2016YFC0402301)
【分类号】：S157

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