In order to understand the dynamics of soil water-stable aggregates and the relationship with soil physico-chemical properties on abandoned arable land in the eroded hilly area of the Loess Plateau

11 aban- doned arable lands with different ages of Robinia pseudoacacia in Zhifanggou watershed were selected for a systematical study through the approach of substituting the temporal serial with spatial serial.In addition

the correlation between soil water-stable aggregates and physico-chemical properties were examined.Results showed that the content of soil water-stable aggregates increased promptly in the early abandoned stage

in- creased slowly with the extension of the abandonment

and then kept a relatively stable content in the follow- ing years.The content increased by 253.45% in the first 10 year abandonment

but by only 16.42% in the following 40 years.> 0.25 mm aggregates were significantly correlated with soil organic carbon

total nitro-gen

available P

CaCO3

and CEC

but not with total K and available K.It is necessary to close and manage hillsides

as well as keep soil organic carbon in a good balance in order to improve soil structure on abandoned arable land in the eroded hilly area of the Loess Plateau.