Effects of ex situ rice straw incorporation on organic matter content and main physical properties of hilly red soil
稻草易地还土对丘陵红壤有机质和主要物理性质的影响

Two typical land-use types,i.e.,newly cultivated slope land and mellow upland,were selected to investigate the effects of ex situ rice straw incorporation on the organic matter content,field water-holding capacity,bulk density,and porosity of hilly red soil,and to approach the correlations between these parameters.The results showed that ex situ incorporation of rice straw increased soil organic matter content,ameliorated soil physical properties,and improved soil water storage.Comparing with non-fertilization and applying chemical fertilizers,ex situ incorporation of rice straw increased the contents of organic matter(5.8%-28.9%)and >0.25 mm water-stable aggregates in 0-20 cm soil layer,and increased the field water-holding capacity(6.8%-16.2%)and porosity(4.8%-7.7%)significantly(P<0.05)while decreased the bulk density(4.5%-7.5%)in 10-15 cm soil layer.The organic matter content in 0-20 cm soil layer was significantly correlated to the bulk density,porosity,and field water-holding capacity in 10-15 cm soil layer(P<0.01),and the field water-holding capacity in 0-20 cm and 10-15 cm soil layers was significantly correlated to the bulk density and porosity in these two layers(P<0.05).