Do invasive alien plants really threaten river bank vegetation? A case study based on plant communities typical for Chenopodium ficifolium—An indicator of large river valleys

Abstract

Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resident and invasive alien species in vegetation plots along three rivers differing in terms of size and anthropogenic impact were also examined. Finally, the effect of invaders on the phytocoenoses typical for C. ficifolium was assessed. The frequency of C. ficifolium clearly decreased with an increasing distance from the river. Among natural habitats, the species mostly preferred the banks of large rivers. The vegetation plots developing on the banks of the three studied rivers differed in total species richness, the number and cover of resident, diagnostic and invasive alien species, as well as in species composition. Our research indicates that abiotic and anthropogenic factors are the most significant drivers of species richness and plant cover of riverbank vegetation, and invasive alien plants affect this type of vegetation to a small extent.

Impact of the Invasive Alien Macrophyte Ludwigia hexapetala on Freshwater Ecosystems: Evidence from Field Data

“…In this case, it seems that the local bank communities are more resistant to L. hexapetala invasion, probably because these communities are generally more structurally compact than aquatic ones and are, thus, more likely to “build a wall” capable of counteracting the initial establishment and then spread of Ludwigia . Nobis et al [ 55 ] also pointed out that invasive alien aquatic plants have a minimal influence on the species richness and plant cover of bank vegetation, compared to other more relevant drivers such as abiotic and anthropogenic factors.…”

Invasive Alien Species <i>Impatiens glandulifera</i> Royle – Spread Dynamics, Environmental Impacts and Youth Perception of the Problem

“…There are several reasons for the ecological success of Impatiens glandulifera Royle, such as creation of shading conditions for other plants, allelophatic pressure and the effective way of 'impatient' propagation. Due to quick growth up to 2 metres, shading seems to be of high importance in competition with other species, similarly as in aquatic ecosystems [17][18][19][20]. The plant proliferates using cracking seed pods, which when disturbed can propel seed for a distance of several metres due to their ballistic properties [21].…”

Estrutura de um Fragmento de Caatinga Infestado por Cryptostegia madagascariensis Bojer ex Decne

“…As invasões biológicas vêm atraindo gradativamente mais atenção devido aos impactos ambientais e econômicos que elas geram. Atualmente, essas invasões dificultam a conservação da biodiversidade global (Maitre et al, 2015;Padalia et al, 2015), uma vez que espécies invasoras competem por recursos como, luz, nutrientes, água e espaço com espécies residentes Nobis et al, 2018;).…”