Abstract: In order to investigate the role of different vegetation restoration patterns on soil structure in iron tailings,Tangshan Qian'an Malanzhuang Iron tailings were taken as research.This paper selected 5 typical slope woodland tailings,they are Sabina vulgaris,Amorpha fruticosa and Pinus tabuliformis mixed,Amorpha fruticosa,Rhus typhina,Hippophae rhamnoides as the research object,measured in its soil mechanical composition,aggregate content,soil bulk density,soil porosity,soil moisture,and analyzed with bare tailings.The results were as follows:1)Gravel content of 6 plots from high to low was:R.typhina forest(23.1%)>mixed forest(10.4%)>bare tailings(9.2%)>S.vulgaris forest(5.4%)>A.fruticosa forest(4.0%)>H.rhamnoides forest(2.2%);2)Large aggregate content of 6 plots from high to low was:H.rhamnoides forest(33.7%)>A.fruticosa forest(29.3%)>S.vulgaris forest(28.7%)>bare tailings(18.3%)>mixed forest(13.6%)>R.typhina forest(11.7%).Sequence coincides with the reverse sequence of gravel content.3)The bulk of the R.typhina forest was equal to the bare tailings,and others were lower than bare tailings after revegetation.The effect of A.fruticosa forest to bulk seemed to be most prominent,which reduced 12.1%.4)Except non capillary porosity of H.rhamnoides forest lower than bare tailings,total porosity of soil,capillary porosity and non capillary porosity of the rest fields had all increased visibly.The top two plots is S.vulgaris forest and A.fruticosa forest.5)The most obvious improvement effect to field capacity and capillary moisture capacity was S.vulgaris,followed by R.typhina,mixed forest improvement was not significant.In summary,S.Vulgaris and mixed forest types had better comprehensive improvement of physical properties of different deep layer of soil and organic matter.

Key words: soil structure, Iron tailings, vegetation restoration types