Abstract: Studies on the storage of organic matter and the binding status of humus in 15 pairs of fertile and infertile brown earth type vegetable garden soils and their various fractions of microaggregates sampled from different regions of Liaoning province show that fertile soils and their various fractions of microaggregates had a larger amount of organic matter and various binding status of humus and a higher ratio of loosely bound humus vs. total organic matter, but a lower ratio of steady bound humus than infertile soil and their corresponding particle sized microaggregates. The ratio of tightly bound humus vs. total organic matter had a little difference. In both fertile and infertile soils, the smaller size of microaggregates had a larger amount of organic matter and various binding status of humus and a higher ratios of loosely and steady bound humus than the larger sizes of microaggregates, but the ratios of tightly bound humus reversed, indicating that the smaller and the larger sizes of microaggregates played different roles in soil fertility.

Key words: Brown earth type vegetable garden soil, Soil microaggregates, Binding status of humus, Soil fertility