Figure 1.
Examples of active and abandoned farmlands.
(a) arable land in Burgos province, Spain; (b) grassland in a North Adriatic pastoral landscape, Croatia; (c) permanent crops: Olive groves on Lesvos, Greece; (d) agroforestry: Quercus pyrenaica dehesa in León province, Spain (sources: (a) J. Arroyo; (b) I. Kosić; (c) T. Plieninger, T. Kizos; (d) A. Taboada).
Table 1.
Explanatory variables provided by primary studies and additional data sources that were included in the meta-analysis and percentage of observations for which these data could be gathered.
Figure 2.
Map of ecological regions included in the analysis.
Numbers in brackets specify the number of cases considered per ecological region.
Table 2.
Structure of the data set for comparing managed versus abandoned farmlands (number of cases).
Figure 3.
Frequency distribution of effect sizes for plant species richness, animal species richness and animal abundance (A) together and (B) separately.
Mean difference effect size, g, and a mixed (random) effects model were used (PR – plant species richness; AR – animal species richness; AA – animal abundance).
Figure 4.
Effect size (95% CI) of land abandonment for (A) taxon; (B) unit size of study; (C) extent of study area; (D) time since abandonment.
Q-test shows significant different effect sizes between groups (heterogeneity) for taxon (Q = 16.95, P = 0.002) and time since abandonment (Q = 12.68, P = 0.013), but not for extent (Q = 0.86, P = 0.8356).
Table 3.
Summary of the meta-analysis.
Figure 5.
Effect size (95% CI) of land abandonment for (A) previous land use; (B) landform; (C) protected areas; (D) precipitation.
Q-test shows significant different effect sizes (heterogeneity) between groups (A: Q = 18.72, P = 0.009 and B: Q = 9.76, P = 0.0076), but not for C: (Q = 0.31, P = 0.8553). D displays a bubble plot of the relationship between effect size and precipitation, with the size of the bubbles scaled according to the reciprocal of the standard deviation of the effect size.