岩石边坡植被护坡系统的水分平衡及控制

 通过对植被护坡系统水分动态平衡的分析，提出岩石边坡植被护坡系统根层土壤贮水量的基本要求。采用现场降雨试验等方法研究岩石边坡植被护坡系统水分运移的规律，对影响植被护坡系统水分平衡的根层土壤初始贮水量、植被截留量、坡表径流量、边坡坡角、坡表蒸散量及根层土壤萎蔫贮水量等因子进行分析。试验结果表明：若客土配比合理，其渗透性能良好，客土能在较短的时间内获得较大的贮水量，客土中添加适量保水剂、泥炭可明显减缓客土层水分的蒸散，此外，客土中添加保水剂还可降低客土的萎蔫持水量，使客土层中更多的水分成为可供植物利用的有效水；覆盖良好的坡面植被对降雨的截留量不可忽视；为提高降雨的入渗量，须选择适宜的边坡坡角。研究成果可为岩石边坡植被护坡系统的水分平衡及控制提供依据。

MOISTURE BALANCE AND CONTROL OF BIO-SLOPE-ENGINEERING SYSTEM FOR ROCK SLOPE

Based on moisture balance of bio-slope-engineering system，the fundamental requirements of water storage capacity of root layer soil in rock slope protection are put forward. By field rainfall tests，the regulations of moisture migration in bio-slope-engineering system for rock slope are studied. Then，the factors governing moisture balance of bio-slope-engineering system are analyzed，such as initial water storage capacity of root layer soil，vegetation interception，slope surface runoff，slope angle，slope surface evapotranspiration，and wilting capacity of root layer soil. It is shown that carrying soil can obtain larger water storage capacity in a relatively short time if its ratio is reasonable and its permeability is good，and adding a good amount of water retention agents and peats into carrying soil can significantly reduce water evapotranspiration；furthermore，water retention agent can reduce wilting capacity of carrying soil，thus more moisture in carrying soil becomes available for plants. It is also shown that vegetation interception cannot be ignored in a good vegetation-covered slope，and slope angle should be appropriately determined to improve the rainfall infiltration. The results may be helpful for moisture balance and bio-slope-engineering system control for rock slope.