Habitat invasion research: where vegetation science and invasion ecology meet

In the last decade, habitat-oriented studies of plant invasions, performed at broad scales and using large data sets of vegetation plots, have focused on quantifying the representation of alien species in vegetation or habitat types, identifying factors underlying invasions, and exploring the pools of species available for invasion into particular habitats. In this essay we summarize what we have learned, discuss constraints associated with this kind of data and outline promising research topics to which a macroecological perspective of habitat invasions can contribute. Such topics include, among others: integrating species-specific information on invasion status, residence time in the region, biological and ecological traits and phylogenetic relationships into habitat invasion research to better capture the context-dependence of invasions; focusing on the functional role that alien species, relative to natives, play in plant communities; and obtaining insights into the role of pre-adaptation for invasion by comparing the functional composition of habitat species pools in the native range. There is still a strong geographic bias, with detailed assessments across broader ranges of habitat types in large regions available only from Europe, the United States and New Zealand, which call for extension of this research to other continents.