Intensive Tillage Effects on Wheat Production on a Steep Hillslope in the Sichuan Basin, China

Two treatments (5- and 15-tillage operations) were conducted to assess intensive tillage effects on wheat production in the Sichuan Basin, China. After intensive tillage, wheat grain yields were 55% and 41% in areas of soil loss lower than those in areas of soil accumulation by 5- and 15-tillage operations, respectively. The redistribution pattern in soil depth affected wheat production with a logarithmic correlation between them, resulting in wheat aboveground biomass and grain yield increased along the downslope transect. A much larger decline in production with loss of soil depth than the increase in production with increase in depth was found. Therefore, fields subject to these patterns of soil redistribution could be expected to be subject to decline in average yield. The variations suggest that over time crop production reduction would gradually become serious in areas of soil loss by tillage.