Urban sprawl facilitates invasions of exotic plants across multiple spatial scales

Francesco Boscutti,Massimo Buccheri,Francesco Busato,Francesco Lami,Rossella Sibella,Fabrizio Martini,Maurizia Sigura,Elisa Pellegrini,Lorenzo Marini

doi:10.1007/s10530-022-02733-6

Francesco Boscutti, Massimo Buccheri + Show 7 more

Open Access

https://doi.org/10.1007/s10530-022-02733-6

Copy DOI

Abstract

Exotic plant invasions are considered one of the major threats to biodiversity causing important impacts at the population, community, and ecosystem levels. Understanding the drivers of plant invasions across multiple spatial and temporal scales often requires a landscape approach. The effect of landscape composition on biological invasion has been extensively studied, whereas landscape configuration effects were seldom considered or the analyses were limited to single species. Here, we aimed to analyze how the expansion of urban and agricultural areas can affect exotic species richness (both neophytes and archaeophytes) at three spatial scales, namely regional (scale: 37.5 km2), landscape (scale: 7.1 km2) and local (scale: 100 m2). We considered the possible contribution of urban and agricultural areas both in terms of composition (i.e. habitat cover) and configuration (i.e. shape complexity of patches). First, we found that increasing urbanization coupled with high shape complexity of urban elements were major drivers of both neophyte and archaeophyte invasions across heterogeneous landscapes. In particular, shape complexity seemed to be a key driver of plant invasions at large spatial scale, whereas the type of recipient habitat and urban cover determined the exotic success at the patch level. Second, archaeophytes were also affected by agriculture land use, i.e. agricultural patches shape complexity increased their spread at both regional and landscape scales. High shape complexity of highly disturbed habitats is expected to increase the exchange surface that exotic plant use to spread their propagules across the landscape mosaics. Our findings suggest that urban planning aimed at curbing urban fragmentation by both reducing shape complexity and diffuse urban sprawl might greatly improve the resistance of landscapes to biological invasions.

Highlights

Exotic plant invasions are considered one of the major threats to biodiversity (Vilà et al 2010; Simberloff et al 2013; Vilà and Hulme 2017; Pyšek et al 2020) causing important impacts at the population, community and ecosystem levels (Vilà et al 2011; Boscutti et al 2020; Pellegrini et al 2021a)
Our findings suggest that urban planning aimed at curbing urban fragmentation by both reducing shape complexity and diffuse urban sprawl might greatly improve the resistance of landscapes to biological invasions
Clarifying the mechanisms through which exotic species spread across the landscape might inform an effective management/planning aimed at curbing biological invasions

Summary

Introduction

Exotic plant invasions are considered one of the major threats to biodiversity (Vilà et al 2010; Simberloff et al 2013; Vilà and Hulme 2017; Pyšek et al 2020) causing important impacts at the population, community and ecosystem levels (Vilà et al 2011; Boscutti et al 2020; Pellegrini et al 2021a). Urban land use encompasses a large array of disturbed habitats (e.g. roadsides, gardens) that are usually highly invaded (Chytrý et al 2008; Lambdon et al 2008; Aikio et al 2012) and that can act as source of exotic plants that can spread into surrounding habitats (Lippe and Kowarik 2008; Botham et al 2009; Säumel and Kowarik 2010; Kühn et al 2017; Guo et al 2019) While most of these studies have focused on landscape composition, the effects of landscape configuration of urban and agriculture areas have been seldom investigated empirically (but see Chen et al 2017; O’Reilly-Nugent et al 2016)

Objectives

Methods

Results

Discussion

Conclusion