Biology Reference
In-Depth Information
value, but, for instance, in Europe many of the early introduced alien species
(archaeophytes) are now listed as threatened species on national red lists
(Klingenstein and Diwani 2005). Alien species may also provide important
resources for native species in urban areas - e.g. fruits of alien trees as food source
for native birds (Corlett 2005). In heavily disturbed sites, ecosystem impacts by
invasive species are difficult to disentangle from impacts by other disturbance fac-
tors (Didham et al. 2005), and often invasive species are probably not the driver of
ecosystem change (Maskell et al. 2006).
5.3.4 Management Action
In anthropogenic areas, weed management has been long practiced, with a focus on
reducing economic and nuisance weeds, and these experiences from weed science
are also relevant for invasive species research and management (Smith et al. 2006).
The integration of control activities in everyday professional management of agri-
culture, forestry, tourism, landscaping, or maintenance of public infrastructure
should be a priority, as this will reduce overall propagule pressure and invasion
threat to surrounding habitats in a way that is economically efficient and is tailored
to the production systems (mainstreaming invasive species control
sensu
Petersen
and Huntley 2005).
5.3.5 Research Focus
Ecosystem integrity and the direct interactions of invasive species with the native
biota are of lesser research interest in the case of anthropogenic habitat. Rather, the
frameworks of agricultural, urban, and landscape ecology that integrate human
action into ecological theories should inspire research on plant invasions in anthro-
pogenic systems (Kueffer and Hirsch Hadorn, 2008). The study of the urban ecology
of alien species has a long tradition in Europe (cf. Davis 2006). Especially for a
better understanding of the dispersal of weeds in anthropogenic landscapes, an
appreciation of the crucial role of human activity is essential (Benvenuti 2007). The
rise of extensive agriculture and agri-environmental schemes in many European
countries may have important consequences for spread of invasive species (Donald
and Evans 2006). Research is needed to understand how similar changes in other
parts of the world are influencing invasive species patterns on agricultural land,
including areas that practice traditional agriculture (Schneider and Geoghegan
2006). Another main research focus should be the development of effective, efficient,
and environmentally friendly control measures that allow upscaling to large areas.
Weed scientists have much experience in this area of research, and invasion biology
would benefit from better integration of concepts and principles from weed science
(Smith et al. 2006).
