title: Bias and error in understanding plant invasion impacts.
abstract: Quantitative assessments of alien plant impacts are essential to inform management to ensure that resources are prioritized against the most problematic species and that restoration targets the worst-affected ecosystem processes. Here, we present the first detailed critique of quantitative field studies of alien plant impacts and highlight biases in the biogeography and life form of the target species, the responses assessed, and the extent to which spatial variability is addressed. Observed impacts often fail to translate to ecosystem services or evidence of environmental degradation. The absence of overarching hypotheses regarding impacts has reduced the consistency of approaches worldwide and prevented the development of predictive tools. Future studies must ensure that the links between species traits, ecosystem stocks, and ecosystem flows, as well as ecosystem services, are explicitly defined.
authors.affiliation: The Bio-Protection Research Centre, PO Box 84, Lincoln University, Canterbury, New Zealand. philip.hulme@lincoln.ac.nz
authors.forename: Philip E
authors.initials: PE
authors.lastname: Hulme
authors.forename: Petr
authors.initials: P
authors.lastname: Pyšek
authors.forename: Vojtěch
authors.initials: V
authors.lastname: Jarošík
authors.forename: Jan
authors.initials: J
authors.lastname: Pergl
authors.forename: Urs
authors.initials: U
authors.lastname: Schaffner
authors.forename: Montserrat
authors.initials: M
authors.lastname: Vilà
mesh_terms: D015982:Bias; D017753:Ecosystem; D004777:Environment; D058865:Introduced Species; D063148:Plant Dispersal; D018521:Plant Physiological Phenomena