Is there an urban effect in alien plant invasions?

Kühn, Ingolf; Wolf, Janis; Schneider, Aline
December 2017
Biological Invasions;Dec2017, Vol. 19 Issue 12, p3505
Academic Journal
Cities are known to be extraordinarily rich in alien plant species compared to rural environments. This is related to specific attributes of urban areas including the availability of natural resources and habitats (namely geological substrates and land cover), the dispersal pathways and associated propagule pressure due to trade and traffic, and the proximity many urban hubs have to rivers. Here we explored how richness and proportions of alien species introduced after the discovery of the Americas (so-called neophytes), can be explained by environmental covariates along the urbanization gradient from very rural to very urbanized grid cells. We tested whether there is a specific urban effect, either as an interaction effect of urbanized areas that changes these general relationships, or if there is an effect due to specific urban conditions. We found that the environmental covariates explaining richness as well as proportions of neophytes remain largely the same across the rural-urban gradient. There is, however, an effect of urbanized area on neophyte species richness and proportions, which also incorporates strictly urban conditions. Rivers, roads and railroads contribute disproportionately less to the increase of neophyte species diversity in more urbanized areas, which might be due to the already higher number of neophytes in cities. We argue that the conditions determining neophyte richness in cities are not fundamentally different from those in rural environments, but extend on the same environmental axis, i.e. having different positions along the gradient towards the upper end.


Related Articles

  • The ecology of urban areas and their functions for species diversity. Werner, Peter // Landscape & Ecological Engineering;Jul2011, Vol. 7 Issue 2, p231 

    Despite the appearance of an enormous number of publications about urban ecology and species diversity, many issues are simply opened up rather than explained. The ecological complexity of urban areas, i.e., the variety of determinants and the spatial and temporal dynamic of cities, preclude...

  • Effects of Urbanization on Tree Species Functional Diversity in Eastern North America. Nock, Charles A.; Paquette, Alain; Follett, Matt; Nowak, David J.; Messier, Christian // Ecosystems;Dec2013, Vol. 16 Issue 8, p1487 

    Urban forests provide ecosystem services for millions of people. Numerous introductions have elevated tree species richness in cities, which may enhance functional diversity. However, few studies have examined changes in tree community composition or functional diversity with urbanization, even...

  • Island biogeography of urban insects: tenebrionid beetles from Rome tell a different story. Fattorini, Simone // Journal of Insect Conservation;Aug2014, Vol. 18 Issue 4, p729 

    Tenebrionid beetle records from 55 sites in urban Rome (Italy) were used to study the influence of structural parameters (area, isolation, forest cover, and shape) of green spaces on species richness and extinction trends. In line with biogeographical predictions, species richness correlated...

  • Birds of a neotropical green city: an up-to-date review of the avifauna of the city of Xalapa with additional unpublished records. González-García, Fernando; Straub, Robert; García, José; MacGregor-Fors, Ian // Urban Ecosystems;Dec2014, Vol. 17 Issue 4, p991 

    Although urbanization poses severe threats to biodiversity, some wildlife groups manage to thrive within urban areas. Among wildlife, birds are a highly diverse, charismatic and well-known group, establishing complex communities in human settlements around the world, making them suitable...

  • Avian Ecological Diversity as an Indicator of Urban Forest Functionality. Results from Two Case Studies in Northern and Southern Italy. Sanesi, Giovanni; Padoa-Schioppa, Emilio; Lorusso, Leonardo; Bottoni, Luciana; Lafortezza, Raffaele // Arboriculture & Urban Forestry;Mar2009, Vol. 35 Issue 2, p80 

    The article presents two case studies which analyzes avian ecological diversity as an indicator of urban forest functionality. It notes that greenspaces and forest trees are essential to the survival and presence of urban-dwelling species in an area. Point-count method was used for sampling bird...

  • Vegetation in Bangalore's Slums: Composition, Species Distribution, Density, Diversity, and History. Gopal, Divya; Nagendra, Harini; Manthey, Michael // Environmental Management;Jun2015, Vol. 55 Issue 6, p1390 

    There is widespread acknowledgement of the need for biodiversity and greening to be part of urban sustainability efforts. Yet we know little about greenery in the context of urban poverty, particularly in slums, which constitute a significant challenge for inclusive development in many rapidly...

  • Urban birds and planting design: strategies for incorporating ecological goals into residential landscapes. Cerra, Joshua; Crain, Rhiannon // Urban Ecosystems;Dec2016, Vol. 19 Issue 4, p1823 

    Private residential property occupies a major part of the urban land base, yet considerable potential remains for improving the ecological performance of private gardens and landscapes. Ecologically-oriented approaches to design of residential properties, however, are only valuable if they are...

  • Diversity in flowering plants and their characteristics: integrating humans as a driver of urban floral resources. Lowenstein, David; Minor, Emily // Urban Ecosystems;Dec2016, Vol. 19 Issue 4, p1735 

    Urban neighborhoods vary in development intensity and in the life style and demographics of their residents. Decisions made by urban residents affect plant communities, their functional characteristics, and the floral resources they provide. We recorded flowers in front-facing yards in 58...

  • Local and Landscape Correlates of Spider Activity Density and Species Richness in Urban Gardens. OTOSHI, MICHELLE D.; BICHIER, PETER; PHILPOTT, STACY M. // Environmental Entomology;Aug2015, Vol. 44 Issue 4, p1043 

    Urbanization is a major threat to arthropod biodiversity and abundance due to reduction and loss of suitable natural habitat. Green spaces and small-scale agricultural areas may provide habitat and resources for arthropods within densely developed cities. We studied spider activity density (a...

  • Plastic and the Nest Entanglement of Urban and Agricultural Crows. Townsend, Andrea K.; Barker, Christopher M. // PLoS ONE;Jan2014, Vol. 9 Issue 1, p1 

    Much attention has been paid to the impacts of plastics and other debris on marine organisms, but the effects of plastic on terrestrial organisms have been largely ignored. Detrimental effects of terrestrial plastic could be most pronounced in intensively human-modified landscapes (e.g., urban...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics