Abstract: etermination of P-preservation and supply performances of 15 pairs of fertile and infertile brown earth type vegetable garden soils sampled from northern, central and southern Liaoning Province show that in most soil samples tested, fertile soils and their various particle sizes of microaggregates had a larger amount of total and desorbed Pand a higher rate of Pdesorption, but a smaller amount of adsorbed Pthan infertile soils and their corresponding particle sized of microaggregates. The microaggregates of <10μm had a more stronger ability of P-adsorption than those of >10μm in both fertile and infertile soils. The microaggregates of <10μm in test vegetable garden soils had a large potential of Psupply, and their Pdesorption rate was one order of magnitude higher than that of other agricultural soils.

Key words: P-preservation and supply, Brown earth type vegetable garden soil, Soil microaggregates, Soil fertility, biochar, crop growth, combined application of biochar and fertilizer, synergistic effects, roots, gene regulation