Long-term post-fire dynamics of co-occurring woody species in Pinus brutia forests: the role of regeneration mode

Abstract

Regeneration mode is one of the key attributes determining population structure and dynamics of plant species. We investigated long-term patterns after fire in the cover of plant species in a 100-year chronosequence of burned Pinus brutia forests in a humid Mediterranean climate region in Turkey. Significant trends were present in the change of cover in major species through post-fire chronosequence and species with similar trends were clustered in relation to their regeneration modes. Obligate resprouters increased their cover from the early post-fire years to the later stages while cover of obligate seeders with a soil seed bank increased in the early years but then decreased through time. Facultative resprouters were at an intermediate position with an increase in cover until mid-successional stages and then a decrease through time. The cover of the only obligate seeder with a canopy seed bank (P. brutia) followed a linear increasing trend during the succession. When species with the same regeneration mode were grouped the same trends were observed with more explained variances. A few life-history traits were enough to explain the observed trends. Our study shows that regeneration mode is an explanatory functional grouping system for describing long-term post-fire dynamics of Mediterranean Basin woody species. We suggest that regeneration mode must be a major component of any vegetation or forest stand dynamics model in the Mediterranean Basin. This result has important implications for the management of Mediterranean Basin ecosystems and can potentially be extrapolated to other Mediterranean-type fire-prone ecosystems.