A study was conducted on the effect of flooding of arable red soil and various rice-based cropping systems on phosphate retention by soil. Phos-phate retention by red soil increased significantly after flooding. The treatment of early rice-late rice-winter flooding had much more significant effect on the increase in phosphate retention by soil than the treatments of early rice-late rice-winter manure and of early rice-late rice-winter rape. The change in pho-sphate retention by soil was consistent with the change in amorphous Fe oxide content of soils in various cropping system treatments. Rem...
