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The influences of long-term residue and fertiliser management on soil organic carbon (SOC) and related physical properties were investigated in a wheat (Triticum aestivum L.)-corn (Zea may s L.) double-cropping system in the North China Plain.The experiment was initiated in 1981, including 4 treatments: control (no fertiliser);mineral N and P fertilisers;low residue rate plus N and P fertilisers;and high residue rate plus N and P fertilisers.In June 2006, soil samples were taken from the 0-0.05, 0.05-0.10, and 0.10-0.20 m layers to determinate bulk density (Pb), water-stable aggregates,bulk SOC, and aggregate-associated C concentrations.Soil water retention curves and saturated hydraulic conductivity (Ks)were measured using samples collected from the 0-0.05 and 0.05-0.10m layers.The results indicated that residue incorporation significantly increased (i.e.improved) bulk SOC and aggregate-associated C concentration, aggregation, Ks soil matrix and structural porosities, and water retention capacity.The improvements in soil physical properties by mineral N and P fertilisers alone were limited.Residue input significantly (P< 0.05) increased the value of S, an index of soil physical quality.A high correlation existed between S and SOC concentration, and the key soil physical parameters, suggesting that S was an effective parameter for evaluation of soil physical quality.Our study concluded that a combination of residue with mineral N and P fertilisers improved SOC concentration, and consequent soil physical quality under the wheat-com double cropping system.