Effect of drought and nutrient availability on invaded plant communities in a semi‐arid ecosystem

Abstract

Ecosystem functions are heavily dependent on the functional composition of the plant community, i.e., the functional traits of plants forming the community. This, on the one hand, depends on plant occurrence, but on the other hand, depends on the intraspecific variability of functional traits of the species, which are influenced by climate and nutrient availability and affected by plant–plant interactions. To illustrate that, we studied the effects of drought and nitrogen addition (+ N), two important abiotic variables which are changing with ongoing global change, as well as their combined effect on the functional responses of grassland communities in semi‐arid environments of Northern Africa comprising of natural and invasive species. We conducted an experiment where we planted three native species and one invasive plant species in artificial communities of five individuals per species per plot. We exposed these communities to four different treatments: a drought treatment, an N‐addition treatment, the combination between drought and N‐addition, as well as a control. To assess the performance of plants within treatments, we measured selected plant functional traits (plant height, specific leaf area [SLA], leaf dry matter content [LDMC], N content of the leaves [Nmass], specific root length [SRL], and root diameter) for all individuals occurring in our plots, and additionally assessed the above and belowground biomass for each plant individual. We found that the invasive species showed a higher performance (higher biomass accumulation, taller plants, higher SLA, Nmass, SRL, and root diameter as well as lower LDMC) than the native species under drought conditions. The invasive species was especially successful with the combined impact of drought + N, which is a likely scenario in ongoing global change for our research area. Thus, plant functional traits might be a key factor for the invasion success of plant species which will be even more pronounced under ongoing global change.

Plant–soil feedback and plant invasion: effect of soil conditioning on native and invasive Prosopis species using the plant functional trait approach

“…In the current study, higher SOC and STN were found in the soil conditioned by native species and lower SOC and STN when the soil was conditioned by invasive and mixed species. These results go in line with previous research (Wang et al, 2018;Ali and Bucher, 2022;Zhang et al, 2023) confirming that invasive plants can also affect the N and C cycles in the soil by affecting soil microbial communities (Gibbons et al, 2017) and arbuscular mycorrhiza fungi (AMF) (Vogelsang and Bever, 2009;de Souza et al, 2018) due to the allelopathic substances released by invasive species (Torres et al, 2021). These results suggest that alteration in the soil nutrient content by invasive species is vital to facilitate invasion success (Blackburn et al, 2011) in a way to compete with native species (C ̌uda et al, 2015).…”

Root plasticity benefits a global invasive species in eutrophic coastal wetlands

“…For example, variations in specific root length (SRL) and root diameter reflect a mycorrhizal collaboration gradient, representing an investment in soil resource exploration by longer roots or higher mycorrhizal colonization (Bergmann et al., 2020). In response to nutrient enrichment, invasive species could exhibit higher SRL for more efficient nutrient absorption (Huang et al., 2019; Keser et al., 2015) or alternatively produce coarser roots for greater assistance from mycorrhizal fungi in nutrient acquisition (Ali & Bucher, 2022). In addition, root anatomical traits have substantial importance for nutrient absorption and transport (Kong et al., 2017; Lynch et al., 2021).…”