Simulating Mediterranean landscape pattern and vegetation dynamics under different fire regimes
In the Mediterranean Basin, landscape patterns are strongly human-modiﬁed. In recent dec- ades, because of industrialisation and rural exodus, many ﬁelds have been abandoned, generating chan- ges in the landscape pattern. In this framework, I aim to study the effect of landscape pattern on landscape dynamic processes in the Mediterranean Basin using simulation models and considering that ﬁre may interact with landscape pattern. First I generate a gradient of ﬁve artiﬁcial random landscapes. In each landscape I include four species types growing in the Mediterranean Basin, each type with different plant traits (Quercus, Pinus, Erica and Cistus types). In each landscape scenario, each species covers 30% of the landscape but with a different spatial distribution, from the coarsest-grained (L1) to the ﬁnest-grained (L5). Then, the dynamics of each of these ﬁve landscapes were simulated for 100 years using the F ATELAND simulation model. Simulations were run with six ﬁre regime scenarios in each landscape scenario (no ﬁre, mean ﬁre interval of 80, 40, 20, 10 and 5 years). Landscape attributes were computed for the initial and the ﬁnal landscapes. As expected, the results suggest that, as expected, some species in- crease and others decrease depending on the ﬁre re- gime. However, the results also show that different landscape structures produce different dynamics and thus that there is a clear interaction between land- scape pattern and ﬁre regime. For instance, coarse- grained spatial patterns generate slower dynamics than ﬁne-grained patterns, and ﬁre-sensitive species are maintained longer under coarse-grained patterns (i.e., fragmentation accelerates extinction of ﬁre- sensitive species).