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ID:
Resprouting, the ability of plants to regenerate damaged tissues through the production of new shoots, has been posed as a main regenerative mechanism in tropical dry forests (TDF) affected by human activities. Although resprouts are a remarkable feature of early regenerating forests in dry lands, their contribution to the whole process of forest regeneration is poorly documented. Furthermore, we do not understand how resprouting ability relates to other forest regeneration mechanisms like dispersal limitation or niche differentiation. Here, using data from two TDF sites where forest regeneration has been monitored through time, we: 1) assess the effect of resprouting on the structure and species composition of regenerating forests, and 2) evaluate how resprouting ability relates to plant traits related to dispersal limitation (dispersal mode, seed size) and niche differentiation (wood density, specific leaf area, and maximum height). We fitted nonlinear models to assess the relative contribution of resprouts to forest recovery, and a path analysis to test for associations among functional traits. Our results show that resprouts are consistently present across regenerating forest stands, but their abundance decay with time since last disturbance and can be highly variable across sites of the same age. We also found resprouting ability to be partially related to dispersal mode, with wind dispersed species being less prone to be represented by resprouts than species with animal dispersal. Together, or results indicate that although resprouting effectively contributes to biomass and species accumulation during forest regeneration, its presence is not wide or uniform across regenerating stands. More important, resprouting interacts with other regenerative mechanisms, particularly dispersal limitation, in shaping tree community recovery: it seems to provide a kickstart for those species that may be limited by seed dispersal, therefore accelerating species accumulation and replacement. We propose a model of forest succession that explicitly integrates resprouting as a mechanism of forest regeneration in TDFs, and identify several research priorities in order to advance on our understanding of the integration of resprouting on successional theory.
Keywords:
resprouts, dispersal limitation, niche differentiation, habitat filtering, regeneration niche