05, ** P < 0.001. Significance of each transition was determined using Fisher’s sign tests Afforestation: grassland to plantation and shrubland to plantation Afforestation of natural grasslands and shrublands resulted in a decrease in species richness and
diversity in all but two cases. The two cases where species richness increased were both in the shrubland to plantation category and were from a publication on the effects of afforestation of a highly endemic but naturally species poor ultramafic grassland in Italy (Chiarucci Selleck BMN-673 and Dedominicis 1995). While overall species richness increased with plantation establishment, specialist and endemic species richness decreased; as such, the increase in total species richness can be attributed to the expansion
of generalist or exotic species (Chiarucci and Dedominicis 1995). Although few afforestation publications reported this measure, those that did reported a decline in richness of narrow/endemic/specialist species (species noted by author as restricted to a particular habitat type), with an average decrease of 47% (±15%) in the three grassland cases where it was reported and 38% (±11; n = 4; P < 0.05) Hedgehog antagonist in shrubland afforestation (Table 1). Exotic species richness was unaffected in one grassland to plantation case (Cremene et al. 2005) while in the other case reported it increased by 470% (O’Connor 2005). Exotic species richness increased in all five shrubland to plantation cases (mean = 36%), but not significantly so (P = 0.41; Fig. 3). Native species richness,
in contrast, decreased in all afforestation cases and significantly so in the shrubland to plantation category (55% decrease, n = 4, P < 0.05; Table 1). Fig. 3 Change in exotic species richness with plantation establishment by category of land use change. *P < 0.05. •Boxplot outliers Primary forest and secondary forest to plantation Monoiodotyrosine Species richness was lower in plantations than in primary forest in 24 of 27 cases with a mean decrease of 35% across all observations (Table 1; Fig. 2; P < 0.001). Eight of the 27 cases were direct comparisons, meaning that plantations replaced natural forests, while 19 of the cases involved an intermediate land use whereby plantations were established on previously deforested land that had been used for another purpose, most often grazing (Appendix 1 includes details on the intermediate land use for each case). Overall, plantations replacing primary forests were 39% (±8%) less species rich than paired primary forest (P < 0.05), while those with an intermediate land use were 33% (±8%) less species rich than paired primary forests (P < 0.01). Likewise, native species richness significantly decreased by 65% (±10%) (P < 0.05) in the five cases reported in the primary forest.