Analytical solution for one-dimensional transient seepage of water
in the unsaturated vegetated soil considering the effects
of roots on hydrological properties
|更新时间:2026-06-25
|
Analytical solution for one-dimensional transient seepage of water
in the unsaturated vegetated soil considering the effects
of roots on hydrological properties
WANG Hao, HOU Hong-bing, JIANG Wen-hao. Analytical solution for one-dimensional transient seepage of water
in the unsaturated vegetated soil considering the effects
of roots on hydrological properties[J]. 2025, 46(11): 3329-3345.
DOI:
WANG Hao, HOU Hong-bing, JIANG Wen-hao. Analytical solution for one-dimensional transient seepage of water
in the unsaturated vegetated soil considering the effects
of roots on hydrological properties[J]. 2025, 46(11): 3329-3345.DOI: 10.16285/j.rsm.2024.1479.
Analytical solution for one-dimensional transient seepage of water
in the unsaturated vegetated soil considering the effects
of roots on hydrological properties
在自然环境和工程场景中,不仅存在裸露非饱和土,也存在被植被覆盖的非饱和土(即非饱和植被土)。针对根系为均匀形的非饱和植被土,在考虑根系对水文特性影响的基础上,通过一些简化假定和变量代换得到了线性化的水分一维瞬态渗流控制方程。采用分离变量和级数变换等方法,求得了非饱和植被土中水分一维瞬态渗流解析解。随后,将该解析解计算结果与现有解析解和相应有限差分解的计算结果比较,验证了其合理性。最后,以一个简单的植被盖层为例,分析了根系相关参数对其阻隔雨水入渗效果的影响。结果表明,与无植被的单一盖层相比,相同降雨场景下植被盖层底部的累计渗漏量CQb较小,且根系土层厚度lg越大,这种阻隔雨水渗漏的效果越为显著。蒸腾速率Tp的增大可明显降低降雨场景下植被盖层底部的渗漏速率,且随着Tp增大,累计渗漏量CQb呈线性减小趋势。与根系体积占比Rv为0且忽略根系对土体水文特性影响的极端情况相比,当Rv值使得根系土的饱和渗透系数减小时,植被盖层阻隔雨水渗漏的效果会增强,反之则会减弱。总的来说,本研究可为非饱和植被土中水分渗流相关工程实践提供科学指导。In the natural environment and engineeringscenarios
there are not only bare unsaturated soils but also unsaturated soilscovered by vegetation (i.e.
unsaturated vegetated soils). For the unsaturatedvegetated soil with a uniform root architecture
on the basis of consideringthe effects of roots on the hydrological properties
thelinearized governing equations for one-dimensional transient seepage of waterare acquired by some simplifying assumptions and variable substitution. Theanalytical solution for one-dimensional transient seepage of water in theunsaturated vegetated soil is obtained through the methods of separation ofvariable and series transformation. Subsequently
the computational results ofthis analytical solution have been compared with those of the existinganalytical solution and the corresponding finite-difference solution to verifyits reasonableness. Finally
a simple vegetated cover is taken as an example toanalyze the influences of root-related parameters on its effectiveness inblocking rainwater infiltration. The results show that the cumulative leakage CQb at the bottom zone of avegetated cover under the same rainfall scenario is smaller than that of asingle cover without vegetation
and an increase in the rooted soil thickness lg enhances the effectivenessof the vegetated cover in blocking rainwater leakage. The increase of thetranspiration rate Tp significantly reduces the leakage rate at thebottom zone of the vegetated cover under the rainfall scenario
and thecumulative leakage CQb tends to decrease linearly with an increase in Tp.Compared with the extreme case where the root volume ratio Rv is zero and the effects of roots on the hydrologicalproperties of soilare ignored
the effectiveness of the vegetated cover in blocking rainwaterleakage is enhanced when the saturated permeability coefficient of the rootedsoil decreases due to the value Rv
and conversely
it is weakened. Overall
this study could provide scientificguidance for engineering practices related to water infiltration in unsaturatedvegetated soils.