Application and suggestion of spraying technique of thick layer substrate to recovery vegetation on highway slope in semiarid areas

In the demonstration project of rock slope re-vegetation in the third construction period of Jingcheng Highway，the slope re-vegetation technique by spraying thick layer substrate was applied in arid and semi-arid areas of China. The research indicates that the technique can basically solve the problem of slope re-vegetation in arid and semi-arid areas，whereas disposition of the substrate for vegetation growing，thickness of sprayed substrate，the way of spraying substrate，selection of vegetation species and regulation of species proportion still need to be improved．Results of this research can afford us technical references for the slope re-vegetation under the similar conditions in arid and semi-arid areas of north China.