Abstract: A three-year experiment was conducted to study the effects of wheat/maize/soybean with total no-tillage and mulching (NTM), wheat/maize/soybean with part no-tillage and part mulching (PTM), wheat/maize/soybean with total tillage without mulching (TWM), and wheat/maize/sweet potato with total tillage without mulching (TWMS) on the soil and water conservation, soil fertility, and crop output value in a sloping land of Southwest China. The　average soil erosion amount and surface runoff of NTM were significantly lower than those of the other three planting systems, being 1189 kg·hm^-2and 215 m³·hm^-2, and 10.6% and 84.7% lower than those of TWMS, respectively. The soil organic matter, total N,  available K and available Ncontents of NTM were increased by 15.7%, 18.2%, 55.2%, and 25.9%, respectively, being the highest among the test planting systems. PTM and TWM took the second place, and TWMS pattern had the least. NTM had the highest annual crop output value (18809 yuan·hm^-2) and net income (12619 yuan·hm^-2) in three years, being 2.2%-20.6% and 3.8%-32.9% higher than other three planting systems, respectively. In a word, the planting system　wheat/maize/soybean was more beneficial to the water and soil conservation and the improvement of soil fertility and crop output value, compared with the traditional planting system wheat/maize/sweet potato.

Key words: planting system, soil and water loss, soil fertility, output value, region, paddy field, reactive N loss, N application rate, field management measure, yield, partial factor productivity.