Large‐scale spatial dynamics of plants: a response to Freckleton & Watkinson

摘要: Metapopulation theory (summarized by Hanski 1999) is one of the most influential developments in ecology recent decades, for example as a cornerstone conservation biology, and theoretical basis studies dispersal distribution abundance species. A synthesis metapopulation landscape has been regarded key to analyses ecological consequences ongoing changes (Wiens 1997). Although successfully applied many regional systems animal populations, usefulness plants still open debate. As Husband & Barrett (1996) Eriksson concluded, rather few have documented metapopulations plants, same holds other forms dynamics, e.g. source-sink populations remnant populations. In paper, Freckleton Watkinson (2002) critically reviewed plant metapopulations, with objectives assessing whether really are suggesting new typology different dynamics. stress, we agree, that these issues not merely semantic. The concepts dynamics only determine ways which empirical performed, but also influence interpretation data (illustrated claiming, showing, existence metapopulations) modelling spatial begin listing four criteria must be fulfilled order regard population metapopulation: (i) suitable habitat occurs discrete patches may occupied or unoccupied; (ii) all local measurable extinction risk; (iii) interconnected dispersal, allowing possibility re-colonization; (iv) completely synchronized their If met, cannot inferred from processes, understood without referring patterns processes. conclude that, given criteria, very cases exist where documented. Indeed, there number reasons why develop way short-lived mobile animals. long-lived life cycle stages (e.g. seeds vegetative ramets) means persist long time even though patch become unsuitable. Successful recruitment sporadic, therefore recolonization unlikely after extinction. Dispersal over distances governed chance events. definition 'long distance' differ between species, it no more than hundred metres (Cain et al. 2000). Suitable difficult define, suitability likely continuous function abiotic biotic environmental factors. propose using concept describing would described non-equilibrium conclusion reached fragmented habitats (Eriksson Ehrl~n 2001). We agree assess general fulfil metapopulations. However, disagree suggestions on believe conclusions concerning difficulties documenting interpreted indicating processes sufficient understanding although acknowledge this intention. three here: comment suggested (2002); suggest how might importance distributions irrespective metapopulations; argue should developed further tool being replaced concepts.