Abstract:By employing soil core method,an investigation in the semi-arid loess hilly area was made on the vertical distribution of fine root characteristics and soil properties in the recovery of typical plantations. Results showed that fine root biomass,root length density(RLD),root surface area,and specific root length(SRL) decreased significantly as soil depth increased. In the 0—60 cm soil layer,the averages of the fine root biomass,RLD,and root surface area for 14 a Hippophae rhamnoides(HR) were the highest; for 30 a Robinia pseudoacacia(RP),less; and for 10 a RP,the lowest. The SRL of 10 a RP was the highest and the SRLs of 14 a HR and 30 a RP were the lowest. Dry layers obviously existed below soil depth of 150 cm in different plantations and the difference between arbor and shrub forests did not influence them significantly. Soil dry degree increased with the increasing of growth age. The improvement of tree forest to soil bulk density,which was greater than that of the two shrub forests,increased with the increasing of growth age. The vertical distribution of soil organic carbon was similar to roots. In the 0—60 cm soil layer,organic carbon contents of 24 a HR and 50 a RP were the highest and organic carbon content of 10 a RP was the lowest.