Seed bank dynamics and climate change in semi-arid ecosystems: a focus on physically dormant species

Resumen

The dynamics surrounding seeds are arguably the most important drivers of population persistence in semi-arid ecosystems. To fully understand plant population persistence and, in particular, to predict the impacts of changing climatic conditions, we need to develop a clearer picture of the ecological consequences of variation in seed dormancy and germination. In this review, I focus on seeds with physical dormancy in semi-arid regions, looking at the mechanistic effects of climate on seed bank dynamics. Both pre-dispersal and post-dispersal environment effects are considered. Knowledge is lacking in the understanding of the effects of changing climate on seed production, dormancy-breaking temperature thresholds, seed longevity and seed vigour. While lessons can be learnt from the broader range of studies conducted in the agricultural sector, there is a limit as to how the results from such studies can be applied to wild species in natural ecosystems. A concerted effort to increase the amount of ecological research in native environments is needed to gain a better understanding of the effects of climate change on biodiversity.