Study on Water Migration and Evolution Characteristics of Ecologically Protected Loess Slopes with Different Inclinations
-
摘要:
黄土边坡广泛分布于中国西北地区，在强降雨条件下极易发生失稳灾害。生态防护已成为保护黄土边坡的有效手段，但不同坡度的生态防护黄土边坡，会导致其内部水分迁移特征及防护效果的差异。因此，为研究不同坡度对生态防护黄土边坡水分迁移与演化特征的影响，本研究以45°和60°两个坡度的生态防护黄土边坡模型为基础，采用时间序列分析法和Hydrus-2D水分迁移模拟软件，解释了生态防护黄土边坡的水分动态演化规律，揭示了降雨强度、降雨历时和植物生长周期对含水率响应模式的影响，并分析了不同防护阶段和不同坡度下边坡土壤水分迁移的规律。研究结果表明，整个监测期间，60°边坡的整体含水率略低于45°边坡，且60°边坡的土壤水分在坡面下部随土层分布的差异性更加显著，而45°边坡在坡顶时表现更明显；随着降雨强度的增加，坡体内部水分对降雨事件响应的滞后时间显著缩短，而边坡内部水分响应的滞后时间及其达到最强响应的滞后时间则随着降雨事件历时的延长而相应增加，植被防护能够有效增大边坡水分对降雨响应的滞后时间，60°边坡内部对所研究降雨事件响应的滞后时间均慢于45°边坡；针对强降雨事件，生态防护可以有效降低水分入渗速率，不同防护时期水分迁移速率表现为：防护前期＞防护中期＞防护后期，同时植物对60°边坡的水分迁移速率影响更为显著，且60°边坡水分入渗响应速率比45°边坡更慢。
Abstract:Loess slopes are widely distributed in northwest China and are particularly susceptible to instability during heavy rainfall. Ecological protection has emerged as an effective means of safeguarding these slopes; however, varying ecological protection methods can lead to differences in the characteristics of internal water migration and overall protective efficacy. Therefore, this study aims to investigate the effects of different slope angles on the water migration and evolution characteristics of ecologically protected loess slopes. To achieve this, time series analysis and Hydrus-2D simulation software were utilized to elucidate the dynamic evolution of water within ecologically protected loess slopes, focusing on slope models with angles of 45° and 60°. The study revealed how rainfall intensity, duration, and plant growth stages impact the water content response model and examined the rules governing soil water transfer under different protection stages and slope angles. The results indicate that during the whole monitoring period, the overall moisture content of the 60° slope is slightly lower than that of the 45° slope, and the soil moisture distribution of the 60° slope with soil layer was more pronounced in the lower part of the slope, while the 45° slope is more obvious at the top. As rainfall intensity increased, the response lag time of internal slope water to rainfall significantly decreased, whereas extending the duration of rainfall events led to an increase in both the response lag time and the time to reach peak response. Vegetation protection effectively prolonged the lag time of the response of water inside slope to rainfall events. Additionally, the response of the 60° slope was slower than that of the 45° slope. For intense rainfall events, ecological protection can effectively reduce the water infiltration rate, and the water migration rate in different protection periods is as follows: early protection ＞ middle protection ＞ late protection. Furthermore, the effect of vegetation on the water migration rate was more significant on the 60° slope, where water infiltration occurred more slowly than on the 45° slope.
-
Key words:
- ecological slope protection /
- slope /
- water migration and evolution /
- time series analysis /
- Hydrus2D /
- loess plateau
-
-
表 1 基材材料配比
Table 1. Substrate material ratio
添加材料 黄土(%) 瓜尔胶(%) 木纤维(%) SAP(%) 改良剂(%) 基层 97.3 1 1.5 0.1 0.1 面层 94.3 0.5 5 0.1 0.1 
下载: 导出CSV
表 2 土样水力特征参数
Table 2. Hydraulic characteristic parameters of soil samples
土样类型 深度（cm） $ {\theta _{\text{r}}} $ （cm3/cm3）$ {\theta _{\text{s}}} $ （cm3/cm3）$ \alpha $ （cm−1）n $ {{\text{K}}_{\text{s}}} $ （cm/min）l 基材 0～7 0.1797 0.4240 0.0077 1.6201 0.019 0.5 黄土 7～67 0.0766 0.3537 0.0077 1.4940 0.0018 0.5 注：l为孔隙连通性参数。θr和θs为剩余水含量和饱和水含量，Ks为饱和水力传导度，参数α和n为影响水力函数形状的经验系数。
下载: 导出CSV
表 3 水分胁迫响应函数参数
Table 3. Parameters of the moisture stress response function
参数 数值 提取水分压头Po(mm) −10 提取水分压力水头最大速率Popt(mm) −25 极限压头P2H、P2L(mm) − 1000 凋萎点压头P3(mm) − 8000 潜在蒸腾速率r2H（cm/d） 3.47×10−4 潜在蒸腾速率r2L（cm/d ） 6.94×10−5
下载: 导出CSV
表 4 各量级降雨特征统计
Table 4. Statistics of rainfall characteristics of each magnitude
降雨类型 降雨次数 占总降雨次数的比例（%） 总降雨量（mm） 平均降雨量（mm） 占总降雨量的比例（%） 微量降雨 2 11.1 0.2 0.1 0.1 小雨 3 16.7 6.1 2.0 2.0 中雨 8 44.4 94.9 11.9 31.8 大雨 3 16.7 103.8 34.6 34.7 暴雨 2 11.1 93.8 46.9 31.4 总计 18 100 298.8 12.5 100
下载: 导出CSV
表 5 5次代表性降雨事件
Table 5. 5 Representative rainfall events
降雨事件 降雨日期 降雨量（mm） 降雨历时（h） 降雨等级 降雨特征 A 7.28 22.7 16.4 大雨 持续较强降雨 B 7.30 8 10.1 中雨 短时中等降雨 C 8.20 35 10.4 暴雨 短时强降雨 D 9.23~9.26 44.1 130.8 h 小雨-中雨 持续弱-中等降雨 E 11.03 8.2 12.7 中雨 短时中等降雨
下载: 导出CSV
-
[1] 包含, 马扬帆, 兰恒星, 等 . 基于微结构量化的含渐变带黄土各向异性特征研究[J]. 中国公路学报,2022 ,35 （10 ）:88 −99 .BAO Han, MA Yangfan, LAN Hengxing, et al . Anisotropic Characteristics of Loess with Gradation Zone based on Microstructure Quantification[J]. China Journal of Highway and Transport,2022 ,35 （10 ）:88 −99 .[2] 包含, 尹晓晴, 兰恒星, 等 . 基于微结构量化的含渐变带天然黄土渗透各向异性研究——以延安新区Q1黄土为例[J]. 岩土工程学报,2023 ,45 （4 ）:730 −738 .BAO Han, YIN Xiaoqin, LAN Hengxing, et al . Permeability anisotropy of natural loess with gradation zone: case study of Q1 loess in Yan'an New District[J]. Chinese Journal of Geotechnical Engineering,2023 ,45 （4 ）:730 −738 .[3] 包含, 敖新林, 高月升, 等 . 黄土边坡典型护坡植被的根系加固力学效应演化分析[J]. 中国公路学报,2024a ,37 （6 ）:98 −110 .BAO Han, AO Xinlin, GAO Yuesheng, et al . Evolution Analysis of Root Reinforcement Mechanical Effect of Typical Plant Protection on Loess Slope[J]. China Journal of Highway and Transport,2024a ,37 （6 ）:98 −110 .[4] 包含, 王耿, 晏长根, 等. 公路建设碳排放核算与岩土工程低碳措施及碳补偿研究综述[J/OL]. 中国公路学报, 2024b, 1−44[2024-10-22]. BAO Han, WANG Geng, YAN Changgen, et al. Highway Construction Carbon Emission Assessment and Low-Carbon Measures and Carbon Compensation for Geotechnical Engineering: A Review[J/OL]. China Journal of Highway and Transport, 2024b, 1−44[2024-10-22]. [5] 黄少平, 陈俊毅, 肖衡林, 等 . 不同坡度植被边坡降雨入渗和径流侵蚀规律的试验研究[J]. 岩土力学,2023 ,44 （12 ）:3435 −3447 .HUANG Shaoping, CHEN Junyi, XIAO Henglin, et al . Test on rules of rainfall infiltration and runoff erosion on vegetated slopes with different gradients[J]. Rock and Soil Mechanics,2023 ,44 （12 ）:3435 −3447 .[6] 郭倩怡, 王友林, 谢婉丽, 等 . 黄土湿陷性与土体物性指标的相关性研究[J]. 西北地质,2021 ,54 （1 ）:212 −221 .GUO Qianyi, WANG Youlin, XIE Wanli, et al . Study on Correlation between Loess Collapsibility and Soil Physical Property Index[J]. Northwestern Geology,2021 ,54 （1 ）:212 −221 .[7] 李鹏. 黄土区草地植被水土保持作用机理试验研究[D]. 咸阳: 西北农林科技大学, 2003. LI Peng. Experimental studies on the functional mechanics ofsoil andwater conservation ofgrassland vegetation in loess area[D]. Xianyang: Northwest Sci-Tech University of Agriculture and Forestry, 2003. [8] 刘黎明, 宋岩松, 钟斌, 等 . 植被混凝土生态修复技术研究进展[J]. 环境工程技术学报,2022 ,12 （3 ）:916 −927 .LIU Liming, SONG Yansong, ZHONG Bin, et al . Research progress on ecological restoration technology of vegetation concrete[J]. Journal of Environmental Engineering Technology,2022 ,12 （3 ）:916 −927 .[9] 申佩佩, 马振波, 邓士伟 . 生态护坡优势及其应用[J]. 河北水利,2020 （3 ）:38 −39 .SHEN Peipei, MA Zhenbo, DENG Shiwei . Advantages of Ecological Slope Protection and its Application[J]. Hebei Water Resources,2020 （3 ）:38 −39 .[10] 孙萍萍, 张茂省, 冯立, 等 . 黄土水敏性及其时空分布规律[J]. 西北地质,2019 ,52 （2 ）:117 −124 .ZHANG Pingping, ZHANG Maosheng, FENG Li, et al . Water Sensitivity of Loess and Its Spatial-Temporal Distribution on the Loess Plateau[J]. Northwestern Geology,2019 ,52 （2 ）:117 −124 .[11] 张剑雄, 谷丰, 朱波, 等 . 林草恢复对热水河小流域侵蚀区土壤团聚体稳定性与有机碳氮特征的影响[J]. 草业科学,2021 ,38 （6 ）:1012 −1023 .ZHANG Jianxiong, GU Feng, ZHU Bo, et al . Effects of forest and grass restoration on soil aggregate stability, and organic carbon and nitrogen characteristics in an eroded area of the Reshui River[J]. Pratacultural Science,2021 ,38 （6 ）:1012 −1023 .[12] 周凤玺, 周志雄, 邵生俊 . 非饱和黄土的增湿湿陷变形特性分析[J]. 岩土工程学报,2021 （S1 ）:36 −40 .ZHOU Fengxi, ZHOU Zhixiong, SHAO Shengjun . Wetting deformation properties of unsaturated collapsible loess[J]. Chinese Journal of Geotechnical Engineering,2021 （S1 ）:36 −40 .[13] 朱冰冰, 李占斌, 李鹏, 等 . 草本植被覆盖对坡面降雨径流侵蚀影响的试验研究[J]. 土壤学报,2010 ,47 （3 ）:401 −407 .ZHU Bingbing, LI Zhanbin, LI Peng, et al . Effect of Grass Coverage on Sediment Yield of Rain on Slope[J]. Acta Pedologica Sinica,2010 ,47 （3 ）:401 −407 .[14] 朱立峰 . 黑方台滑坡群控制因素与外动力条件分析[J]. 西北地质,2019 ,52 （3 ）:217 −222 .ZHU Lifeng . Analysis of Control Factors and External Force for the Landslides in Heifangtai Area[J]. Northwestern Geology,2019 ,52 （3 ）:217 −222 .[15] GB/T 50123-2019, 水利部水利水电规划设计总院 , 南京水利科学研究院. 土工试验方法标准[S]. 中华人民共和国住房和城乡建设部, 国家市场监督管理总局, 2019. [16] Bai W S, Li R J, Pan J Y, et al . Measured Rainfall Infiltration and the Infiltration Interface Effect on Double-Layer Loess Slope[J]. Water,2023 ,15 （14 ）:2505 .[17] Balzano B, Tarantino A, Ridley A . Preliminary analysis on the impacts of the rhizosphere on occurrence of rainfall-induced shallow landslides[J]. Landslides,2019 ,16 :885 −1901 .[18] Bao H, Liu C Q, Lan H X, et al . Time-dependency deterioration of polypropylene fiber reinforced soil and guar gum mixed soil in loess cut-slope protecting[J]. Engineering Geology,2022 ,311 :106895 .[19] Bao H, Liu L, Lan H X, et al. Evolution of high-filling loess slope under long-term seasonal fluctuation of groundwater[J]. Catena, 2024, 238. [20] Chatterjee D , Krishna A M . Effect of Slope Angle on the Stability of a Slope Under Rainfall Infiltration[J]. Indian Geotechnical Journal,2019 ,49 （6 ）:708 −717 .[21] Feddes R A, Kowalik P J, Zaradny H . Simulation of field water use and crop yield[J]. Soil Science,1978 ,129 （3 ）:193 .[22] Feng W, Li Y. Measuring the ecological safety effects of land use transitions promoted by land consolidation projects: the case of Yan’an City on the Loess Plateau of China[J]. Land, 2021, 10(8): 783. [23] Green W H, Ampt G A . Studies on soil physics[J]. The Journal of Agricultural Science,1911 ,4 （1 ）:1 −24 .[24] Hencher S R . Preferential flow paths through soil and rock and their association with landslides[J]. Hydrological Processes,2010 ,24 （12 ）:1610 −1630 .[25] Ismail M A M , Hamzah N H. Study on the Response of Unsaturated Soil Slope Based on the Effects of Rainfall Intensity and Slope Angle. 3rd International Conference of Global Network for Innovative Technology (IGNITE)[R], Malaysia, 2016. [26] Jia Z L, Yan C G, Li B, et al. Performance test and effect evaluation of guar gum-stabilized loess as a sustainable slope protection material[J]. Journal of Cleaner Production, 2023, 408. [27] Jin Z, Guo L, Lin H, et al . Soil moisture response to rainfall on the Chinese Loess Plateau after a long-term vegetation rehabilitation[J]. Hydrological Processes,2018 ,32 （12 ）:1738 −1754 .[28] Kim Y, Lee S . Field Infiltration Characteristics of Natural Rainfall in Compacted Roadside Slopes[J]. Journal of Geotechnical and Geoenvironmental Engineering,2010 ,136 （01 ）:248 −252 .[29] Lann T, Bao H, Lan H X, et al. Hydro-mechanical effects of vegetation on slope stability: A review[J]. Science of the Total Environment, 2024, 926. [30] Liu B, Xie Y, Li Z, et al . The assessment of soil loss by water erosion in China[J]. International Soil and Water Conservation Research,2020 ,8 :430 −439 .[31] Liu X, Lan H, Li L, et al . An ecological indicator system for shallow landslide analysis[J]. Catena,2022 ,214 :106211 .[32] Luo W Q, Gong J, Zhang Z Y, et al. Research on dynamic effects of rainfall and groundwater on stability of slope[C]. International Symposium on Hydrogeology and the Environment (HE 2000), Wuhan, Peoples R China, 2000. [33] Ma Y F, Bao H, Yan C G, et al. Mechanical properties and microstructure evolution of two ecological slope-protection materials under dry-wet cycles[J]. Journal of Cleaner Production, 2023, 416. [34] Qin C B, Wang R, Chen W K, Shi Y S, et al . Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects[J]. Forests,2024 ,15 :133 .[35] Richards L A . Capillary conduction of liquids through porous mediums[J]. Physics,1931 ,1 （5 ）:318 −333 .[36] Shao W, Bogaard T, Bakker M . The influence ofpreferential flow on pressure propagation and landslide triggering of the Rocca Pitigliana landslide[J]. J Hydrol,2016 ,543B :360 −372 .[37] Sreenivas L, Johnston J R, Hill H O . Some relationships of vegetation and soil detachment in the erosion process[J]. Soil Science Society of America Journal,1948 ,12 （C ）:471 −474 .[38] Suched L, Kittikhun K, Gayuh A P . Performance of geosynthetic cementitious composite mat and vetiver on soil erosion control[J]. Journal of Mountain Science,2020 ,17 :1410 −1422 .[39] Sun P, Wang H, Wang G, et al . Field model experiments and numerical analysis of rain-fall-induced shallow loess landslides[J]. Engineering Geology,2021 ,295 :106411 .[40] Tu X, Kwong A, Dai F, et al. Field monitoring of rainfall infiltration in a loess slope and analysis of failure mechanism of rainfall-induced landslides[J]. Engineering Geology. 2009; 105: 134–150. [41] Van G M . A closed-form equation for predicting the hydraulic conductivity of unsaturated soils[J]. Soil Science Society of America Journal,1980 ,44 （5 ）:892 −898 .[42] Waldron L J, Dakessian S . Soil reinforcement by roots: calculation of increased soil shear resistance from root properties[J]. Soil Science,1981 ,132 （6 ）:427 −435 .[43] Wang Q, Callisti M, Miranda A, et al . Evolution of structural, mechanical and tribological properties of Ni–P/MWCNT coatings as a function of annealing temperature[J]. Surface and Coatings Technology,2016 ,302 :195 −201 .[44] Wang G L, Li T L, Xing X L, et al . Research on loess flow-slides induced by rainfall in July 2013 in Yan'an, NW China[J]. Environmental Earth Sciences,2015 ,73 （12 ）:7933 −7944 .[45] Weng X, Sun Y, Zhang Y, et al . Physical modeling of wetting-induced collapse of shield tunneling in loess strata[J]. Tunnelling and Underground Space Technology,2019 ,90 :208 −219 .[46] Wu L Z, Zhou Y, Sun P, et al . Laboratory characterization of rainfall-induced loess slope failure[J]. Catena,2017 ,150 :1 −8 .[47] Yang Y D, Liu H, Li H F, et al . Planting in ecologically solidified soil and its use[J]. Open Geosciences,2022 ,14 （1 ）:750 −762 .[48] Zhang S, Han T, Lu Y, et al. Experimental study of water migration characteristics in compacted loess subjected to rainfall infiltration[J]. PLOS ONE, 2022, 17(9). [49] Zhao B, Zhang L, Xia Z, et al. Effects of rainfall intensity and vegetation cover on erosion characteristics of a soil containing rock fragments slope[J]. Advances in Civil Engineering. 2019, 1–14. [50] Zhou B B, Wu J G, Anderies J M . Sustainable landscapes and landscape sustainability: A tale of two concepts. Landsc[J]. Urban Plan,2019 ,189 :274 −284 . -
图(12)
表(5)
计量
- 文章访问数: 117
- PDF下载数: 0
- 施引文献: 0