The consequences of recruitment limitation: reconciling chance, history and competitive differences between plants

Plant competition for space is studied using analytical and simulation models. Here, the interaction is viewed as a local competition between juveniles of different species for environmentally variable sites vacated by the random deaths of adults. Because plants are sedentary and have finite fecundity, often only a subset of species will compete for an available site. When a dominant species is recruitment limited, inferior competitors will win some sites by forfeit. It is shown that recruitment limitation allows “winning-by-forfeit” which lessens the effect of competitive asymmetries and slows population and community dynamics. Moreover, since recruitment limitation is likely to be most pronounced in highly diverse communities because of the rarity of many species, it is suggested that there is no conflict between the hypothesis that species-rich plant communities are more influenced by chance and history than regulated by competition, and observations of strong interspecific differences among plants.