Fig. 1. Analysis framework for evaluating the effect of farmland reforestation on ecological connectivity

Fig. 2. Location of the agro-pastoral ecotone of northern China

Fig. 3. A diagram showing circuit theory for landscape connectivity

Fig. 4. Reforested farmland during the period 2000-2015 (a. spatial pattern; b. reforested area and reforestation rate in each county)

Fig. 5. Spatial distribution of ecological sources and key conservation areas (a and b. sources in 2000 and 2015; c and d. key areas in 2000 and 2015)

Fig. 6. Spatial pattern of ecological corridors and obstacles (a and b. corridors in 2000 and 2015; c and d. obstacles and the occupation of land use types in 2015)

Fig. 7. Spatial distribution of pinch points (a. 2000; b. 2015)

Fig. 8. Correlations of farmland reforestation and ecological connectivity

Fig. 9. Comparison of the actual and counterfactual scenarios in terms of ecological sources, corridors, pinch points and patch importance (Type I: unchanged importance; Type II: upgraded importance; Type III: downgraded importance; Type IV: gain of important patches; and Type V: loss of important patches)