Conservation agriculture in western China increases productivity and profits without decreasing resilience

摘要

This study examined the economic and risk effects of conservation agriculture (CA) in western China using nine years of data from an agronomic field experiment and a case study for a typical crop-livestock farm. A CA system of a wheat-pea rotation with no-tillage and stubble retention was compared with the current practice of the same rotation but with conventional tillage and stubble removal. Risk was examined by computing the resistance and resilience of grain yields to climate shocks at the field scale, along with calculating the stability of yields and profits at the field and farm scale. Climate shocks were defined using the standardized precipitation evapotranspiration index. Resistance indicated the proximity of grain yields during a climate shock to average yields. Resilience indicated the rate of return towards average grain yields after a climate shock. At the field scale, CA increased grain yields by an average of 19.6% and increased profits without negatively affecting resistance or resilience. At the farm scale, CA increased profits by an average of 5%, increased the stability of profits by 33%, and reduced labor demands. Despite these gains, the adoption of CA in western China remains low. Results suggest that at present the private gains to farmers are not large enough to encourage the more widespread?adoption of CA. Therefore, because CA also produces public benefits for conservation of the environment such as reduced erosion, financial incentives may be considered to assist CA adoption in specific farming systems.