Abstract: Soils have been investigated in midstream and downstream areas of the Shiyang River that had been previously cultivated but abandoned for different numbers of years. The research investigated physical and chemical properties (water content, organic carbon, nitrate nitrogen, ammonium nitrogen, total phosphorus, available phosphorus, total potassium, quick-available potassium, slow-available potassium) and microbes (microbial biomass C, N, P and the number of microorganisms). Results showed that soil ammonium nitrogen and total phosphorus content decreased the longer the land had been abandoned, while water content, organic carbon, nitrate nitrogen, available phosphorus, available potassium and slow-available potassium increased. There were however no significant differences in total potassium and quick-available potassium over the years. Microbial biomass C decreased in 30-40 cm soil layers in land abandoned for shorter periods (1-5 yrs), but increased for longer periods (8-31 yrs). The variability of microbial biomass N increased initially (1-4 yrs), then decreased (4-8 yrs) and finally stabilized (8-31 yrs). Except for 0-10 cm soil layers, the variability of soil microbial biomass P decreased at first (1-2 yrs), then increased (2-8 yrs) and finally decreased (8-31 yrs). Bacteria were the most frequent, followed by actinomycetes, and fungi were the least numerically significant during all stages.