| Abstract In order to reveal the effects of plantation on soil anti-erodibility,Robinia pseudoacacia plantation at different ages in Hilly-gully region of Loess Plateau was chosen to analyze the changes of soil anti-erodibility,and the slope cropland was used as contrasts.The results indicate that the contents of >0.25 mm soil water-stable aggregates,>0.5 mm soil water-stable aggregates,mean weight diameter and organic C increase significantly compared with slope cropland and increase with ages.Aggregate state and aggregate degree are improved markedly compared with slope cropland and declined firstly then raised with increasing of ages.Ratio of soil structure deterioration,dispersive rate and disporsive coefficient take on wavelike drop.Small microaggregates and mechanical composition transform into ones with much bigger diameter.Results of correlation analysis shows that the >0.25 mm soil water-stable aggregates,>0.5 mm soil water-stable aggregates,mean weight diameter and organic C positively correlated with N,available N,available K and total P(P<0.05),but negative with soil density.High negative correlation is observed between ratio of structure deteriorative,dispersive rate,dispersive coefficient and total N,available N,total P.Soil anti-erodibility index(I)rise with increase of ages and can generally reflect the change of soil anti-erodibility.It can be concluded that the poor soil anti-erodibility of slope cropland under erosive environment owing to human cultivation activities is improved greatly by plantation. |
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2010, Vol. 8 