| Popis: |
The soil-root system formatted by plant roots and soil has a good effect in soil reinforcement and slope protection. Setaria viridis is a common species distributing in the three gorges reservoir region. In order to determine the performance of the species in soil reinforcement and slope protection and its variation characteristics on the water-level-fluctuation belt, we tested the tensile strength, anti-scouribility, anti-erodibility and shear resistance of the community soil-root systems. The results showed that the root system of S. viridis community grew better with the increase of altitude under the influence of water level fluctuation. The soil - root system of S. viridis community has an effect on soil reinforcement and slope protection. Its tensile strength of roots ranged from 60 to 90 Kpa/mm2,and its anti-scouribility enhancement coefficient, soil anti-erodibility enhancement coefficient and shear strength of soil-root system reached 0.15 to 0.90, 0.30 to 0.73, and 9 to 24 Kpa respectively. Its effects in soil reinforcement increased with the altitude increases. The correlation analysis indicated that the effects related significantly with root biomass. It is concluded that spatial changes of effects of soil-root systems in its soil reinforcement and slope protection might result from difference of root growth caused by water level fluctuation. |
