Competitors and ruderals go to town: plant community composition and function along an urbanisation gradient

Abstract

Urbanisation is expected to function as a filter for plant species by changing the physiochemical environment, causing species turnover along an urbanisation gradient. Analyses of the functional traits of species characteristic of different urbanisation levels allow for comparisons across studies, irrespective of exact species composition. This study aims to examine how plant species and functional traits vary with urbanisation. An independent dataset obtained through the Global Biodiversity Information Facility was used to validate the identified indicator species. The study was performed in Trondheim, Norway. Indicator species of two different urbanisation levels were identified from a structured plot vegetation survey, and their functional traits were contrasted. The functional trait patterns were compared to patterns identified from an independent GBIF dataset. Changes in species composition along the urbanisation gradient identified a shift in environmental-and anthropogenic variables, filtering species with different functional traits. Indicators of urban areas displayed higher SLA, nitrogen affinity and disturbance tolerance than indicators from non-urban areas. Not all functional trait differences observed between the indicator species from the vegetation survey were recognised in the independent dataset from GBIF. Nevertheless, the overall trends were consistent. Urbanisation favours species adhering to different trait syndromes than species outside of urban areas; disturbance-over stress-tolerance, and species adapted for rapid resource acquisition rather than species adapted for resource conservation.

Host condition, seasonality and environmental factors explain parasite community differences between urban and rural foxes

“…Anthropogenic change, including urbanisation, alters the composition of ecological communities (Kampichler et al 2012;Petersen et al 2021;Wang et al 2017;Dale 2018). As environmental conditions become more suitable for some species and less suitable for others, we observe community turnover along environmental gradients (Legendre and Caceres 2013;Dunson and Travis 1991).…”

Trait variation along an urban–rural gradient in Asian dayflower: the contribution of phenotypic plasticity and genetic divergence

“…The findings of our study offer a novel perspective, suggesting that the association between traits facilitating larger plant and leaf sizes may have also undergone evolutionary changes in urban situations. However, the adaptive significance of the plant-leaf size correlation in urban conditions remains unclear (Petersen et al 2021). Therefore, future studies using transplant experiments with fitness measurements should be conducted to investigate this relationship (cf., Gorton et al 2018).…”

“…2019; Petersen et al . 2021). Urban plant populations often have larger sizes in order to acquire more carbon for reproductive traits than rural populations (Lambrecht et al .…”

Urbanisation and land-cover change affect functional, but not compositional turnover of bird communities

“…The municipality is well-sampled with regards to species occurrence records, in part due to the presence and activity of a university and a University Museum. Birds are particularly well-registered (Petersen et al 2020(Petersen et al , 2021a.…”

“…It has been shown that land-cover and land-use determine species richness differently among different taxa, groups of conservation concern, and functional groups (Petersen et al 2020(Petersen et al , 2021a. In addition to differences in species richness, land-cover affects community composition; changes in landcover are thus likely to cause species turnover.…”