Evaluation of the Effects of Forest on Slope Stability and Its Implications for Forest Management: A Case Study of Bailong River Basin, China
Abstract
:1. Introduction
2. Materials and Methods
2.1. Vegetation and Site Characteristics
2.2. Field Investigation of Root Systems
2.3. Measurement of Root Tensile Strength
2.4. In Situ Direct Shear Measurements
2.5. Estimation of the Mechanical Stabilization Effect of Robinia Pseudoacacia on Slope Material
2.5.1. Additional Cohesion Effect of Fine Roots
2.5.2. Anchoring Effect of Coarse Roots
2.6. Calculation of Slope Stability
3. Results
3.1. Root Distribution
3.2. Tensile Strength
3.3. The Additional Cohesion and Anchoring Effect of Roots
3.4. Calculation of Slope Stability
4. Discussion
4.1. Characteristics of Root Distributions on the Study Slope
4.2. Tensile Strength of the Roots on the Slope
4.3. Influence of Root Anchorage on Slope Stability
4.4. Effect of Planting Location on Slope Stability
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Item | Value |
---|---|
Slope (°) | 39 |
Bulk density (N/cm3) | 17.3 |
Cohesion (kPa) | 1.05 |
Friction angle (°) | 44.7 |
Additional cohesion by roots (kPa) | 15 |
Root Diameter Classes | Fitting Function | Correlation Coefficient |
---|---|---|
d ≤ 1.0 mm | Rd1 = 149.71e−0.192d | R2 = 0.9175 |
1.0 mm ≤ d ≤ 2.0 mm | Rd2 = 6.8147e0.0626d | R2 = 0.4261 |
2.0 mm ≤ d ≤ 5.0 mm | Rd3 = 0.34d2 − 1.86d + 4.65 | R2 = 0.8818 |
5.0 mm ≤ d ≤ 10.0 mm | Rd4 = 0.09z2 − 0.31z + 0.9 | R2 = 0.9153 |
Diameter Classes | F Value | p |
---|---|---|
d ≤ 1.0 mm | 1.567 | 0.248 |
1.0 mm ≤ d ≤ 2.0 mm | 2.567 | 0.118 |
2.0 mm ≤ d ≤ 5.0 mm | 6.20 | 0.014 a |
5.0 mm ≤ d ≤ 10.0 mm | 6.50 | 0.028 a |
Planted Location | With/Without Anchorage | Stability Factor | ||
---|---|---|---|---|
OF | BS | MP | ||
Without vegetation | - | 1.157 | 1.149 | 1.192 |
Upslope | Without | 1.149 | 1.186 | 1.182 |
Middle slope | Without | 1.159 | 1.197 | 1.176 |
Lower slope | Without | 1.163 | 1.192 | 1.197 |
All | Without | 1.202 | 1.27 | 1.266 |
Upslope | With | 1.158 | 1.196 | 1.195 |
Middle slope | With | 1.159 | 1.199 | 1.189 |
Lower slope | With | 1.181 | 1.216 | 1.211 |
All | With | 1.208 | 1.277 | 1.275 |
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Wang, S.; Zhao, M.; Meng, X.; Chen, G.; Zeng, R.; Yang, Q.; Liu, Y.; Wang, B. Evaluation of the Effects of Forest on Slope Stability and Its Implications for Forest Management: A Case Study of Bailong River Basin, China. Sustainability 2020, 12, 6655. https://doi.org/10.3390/su12166655
Wang S, Zhao M, Meng X, Chen G, Zeng R, Yang Q, Liu Y, Wang B. Evaluation of the Effects of Forest on Slope Stability and Its Implications for Forest Management: A Case Study of Bailong River Basin, China. Sustainability. 2020; 12(16):6655. https://doi.org/10.3390/su12166655
Chicago/Turabian StyleWang, Siyuan, Minmin Zhao, Xingmin Meng, Guan Chen, Runqiang Zeng, Qiang Yang, Yi Liu, and Biao Wang. 2020. "Evaluation of the Effects of Forest on Slope Stability and Its Implications for Forest Management: A Case Study of Bailong River Basin, China" Sustainability 12, no. 16: 6655. https://doi.org/10.3390/su12166655