From Income Stability to Income Improvement: Evidence of Risk-Buffering Advantages and Nonlinear Income Effects in Integrated Crop–Livestock Systems

To address escalating natural and market risks in agriculture, integrated crop–livestock systems (ICLS) are increasingly recognized as a production mode combining resilience and sustainability. Using survey data from 372 farm households in Inner Mongolia, China, this study first constructs a directional income volatility indicator and applies the Kruskal–Wallis test together with robust tests for equality of variances to compare the short-term risk-buffering performance of specialized cropping, specialized livestock production, and ICLS. The analysis then focuses on 190 ICLS households and employs Hansen’s threshold model to identify nonlinear constraints on achieving higher income and examine potential equipment misallocation. The results show a stronger short-term risk-buffering advantage of ICLS over the two specialized modes. Livestock inventory scale exhibits a threshold effect: at a lower livestock inventory scale, livestock expansion is significantly associated with lower income, whereas beyond this threshold the marginal effect becomes significantly positive. Crop–livestock structural matching, measured by the livestock–land ratio, constrains the income effect of livestock expansion: once the ratio reaches a certain level, livestock expansion no longer shows a significant negative association with income. In addition, mismatches between machinery investment and production orientation weaken the income performance. These results imply that policy should promote ICLS in a context-specific and moderate manner, guide farmers toward better crop–livestock alignment, and expand agricultural service provision to reduce risks associated with misaligned mechanization.