Abstract: Taking eight artificial plant communities in the greenbelts of Shanghai Outer Ring as test objects and with bare land as the control, this paper studied the amount of litter falls and the characteristics of soil porosity and water-holding, aimed to approach the effects of the litter falls of urban greenbelt plant communities on soil water physical properties. The results showed that in upper soil layer (0-10 cm), soil maximal water-holding capacity, capillary waterholding capacity, minimal water-holding capacity, mass water content, volume water content, capillary porosity, non-capillary porosity, total porosity, and aeration were significantly higher (P<0.05) in greenbelts than in bare land, while soil bulk density was in adverse; but in lower soil layer (10-20 cm), there were no significant differences in these parameters between greenbelts and bare land. The capillary porosity in upper soil layer had significant negative correlation but waterholding characters had less correlation with annual litterfall, and the total porosity and aeration had significant positive correlations but bulk density had significant negative correlation with litter stock. No significant correlations were observed between the water physical properties in lower soil layer and the annual litterfall and litterfall standing stock. It was suggested that the litterfall stock of greenbelt plant communities could effectively improve soil water physical properties, especially the porosity of upper soil layer, and thus, should be reserved during urban greenbelt management.

Key words: Human disturbance, Soil property, Soil microbe, Secondary forest area, Loess Plateau