The roles of plant persistence and lifespan in restoration and community ecology

Abstract. I discuss how persistence and lifespan may profoundly affect plant community ecology and restoration. It is likely that most plants can thrive as adults in environments where they cannot establish themselves. This has three implications. First, ecological restoration explicitly assists plants in their establishment phase, where most mortality normally occurs. This likely leads to unintentional range extensions. Second, the natural or intentional movement of plants in response to climate change partly counts on the niches into which these plants are moving being themselves emptied by climate change. In reality, even if the recruitment niche has indeed shifted, it is likely that the target niche spaces will continue to be filled by adult individuals impervious to this change, for at least their lifespans, which can be very long. Third, it appears that there is a rough match between the lifespans of species in successional sequences and their persistence during succession, perhaps because these species can establish only during relatively small successional windows, but can persist as adults for their own lifespans. This suggests that many successional species last for only a single generation.  Many cases of arrested succession and putative alternative stable states may in fact be anomalous cases of early- and mid-successional species (especially clonal spp.) having uncharacteristically long lifespans. I reviewed 52 published papers on “arrested succession”, adding 12 papers and six species to Royo’s 2006 review of “recalcitrant understories”. Results show that virtually all of the >46 documented suppressing species are long-lived and often clonal: clonal ferns (9), clonal bamboos (³5), other clonal and long-live clump grasses (7), clonal palms (3), clonal ericaceous shrubs (8), other clonal or coppicing spp. (6), and lianas (³5). I suggest that it is the lifespan of these clonal species, more than their rapid vegetative growth, that maintains these arrested states.