Clonal integration and phosphorus management under light heterogeneity facilitate the growth and diversity of understory vegetation and soil fungal communities

Biological invasions and soil salinization have become increasingly severe environmental problems under global change due to sea-level rise and poor soil management. Invasive species can often outcompete native species, but few studies focus on whether invasive alien species are always superior competitors under increasing stressors. We grew an invasive grass species, Oenothera biennis L., and three native grass species (Artemisia argyi Lévl. et Vant., Chenopodium album L., and Inula japonica Thunb.) as a monoculture (two seedlings of each species) or mixture (one seedling of O. biennis and one native species seedling) under three levels of salt treatments (0, 1, and 2 g/kg NaCl) in a greenhouse. We found that invasive O. biennis exhibited greater performance over native C. album and I. japonica, but lower performance compared to A. argyi, regardless of the soil salinity. However, salinity did not significantly affect the relative dominance of O. biennis. Interspecific competition enhanced the growth of O. biennis and inhibited the growth of I. japonica. Although O. biennis seedlings always had growth dominance over C. album seedlings, C. album was not affected by O. biennis at any salt level. At high salt levels, O. biennis inhibited the growth of A. argyi, while A. argyi did not affect the growth of O. biennis. Salt alleviated the competitive effect of O. biennis on I. japonica but did not mitigate the competition between O. biennis and the other two native species. Therefore, our study provides evidence for a better understanding of the invasive mechanisms of alien species under various salinity conditions.

Section: Discussionmentioning

confidence: 99%

Effects of salt stress on interspecific competition between an invasive alien plant Oenothera biennis and three native species

Guo

Liu

et al. 2023

“…Plant diversity of the communities, functions of water conservation, soil conservation, and carbon storage were evaluated by parameters in sections 2.1-2.5, respectively. In these models, we included stand stage [middle aged (i.e., mid-aged) vs. pre-mature vs. mature], forest management (control vs. gap management vs. CTN management), and their interactions as fixed factors (Bai et al, 2020b;Shi et al, 2021;Wang et al, 2022). Post-hoc multiple comparisons for each model were separately conducted if there were significant differences between treatments of stand stage or forest management.…”

Section: Statistical Analysesmentioning

confidence: 99%

“…More importantly, the positive effects of CTN or gap management on diversity of clonal plants, plant diversity, and carbon storage of shrubs and herbs significantly declined with the stand stages (Figures 1, 2, 5). Generally, after CTN or gap management, the multi-species forest structure and differentiation of the niche often caused light heterogeneity of forests, leading to the coexistence of both shade-tolerant and shade-intolerant plants, and consequently might increase the diversity of woody and herbaceous plants (Gong et al, 2021), along with the diversity of clonal plants (i.e., clonal growth plants can easily and rapidly utilize light and soil water) (Shi et al, 2021). Meanwhile, multi-species or heterogeneous forest structure might affect soil moisture by modifying the re-distribution of rainfall and root characteristics, which increase hydraulic conductivity and soil water conservation by increasing the buffer and retention capacity of the multi-species forest canopy and litters (Zhao et al, 2018;Zagyvai-Kiss et al, 2019).…”

Section: Diversity Of Clonal Plants and Ecosystem Service Functions U...mentioning

confidence: 99%

High correlations between plant clonality and ecosystem service functions after management in a chronosequence of evergreen conifer plantations

Song,

Xu,

Yuan

et al. 2023

Self Cite

IntroductionClimate change and mono-afforestation or mono-reforestation have continuously caused a decline in biodiversity and ecosystem services on forest plantations. Key plant functional traits in forests or plantations may affect ecosystem functions after forest management practices. Plant clonality, a key functional trait, frequently links to biodiversity and ecosystem functions and affects the biodiversity–ecosystem functioning relationship. However, little is known about how plant clonality affects ecosystem functions and services of plantations after forest management.MethodsWe conducted a field experiment to discuss the diversity and proportion of clonal plants, plant diversity of the communities, and ecosystem service functions and their relationships under 10 years of close-to-nature (CTN) management, artificial gap management, and control (i.e., without management) in the three stages of C. Lanceolata plantations.ResultsOur results showed that CTN and gap management modes significantly facilitated diversity of clonal plants, plant diversity of the communities, and parameters of ecosystem service functions in C. lanceolata plantations. Moreover, CTN management promoted plant community diversity, soil water conservation, and carbon storage the most in the earlier stand stages. Diversity of clonal plants was significantly positively correlated with ecosystem service functions after forest management. Structural equation modeling analysis indicated that forest gap or CTN management indirectly positively affected ecosystem service functions through increasing diversity of clonal woody plants and plant diversity of the communities.ConclusionOur results indicate a highly positive effect of gap or CTN management on diversity and proportion of clonal plants and on plant diversity of the communities, which link to improvements in ecosystem service functions (i.e., water and soil conservation and carbon storage). The link between forest management, diversity, and ecosystem functions suggests that key functional traits or plant functional groups should be considered to underline the mechanism of traits–ecosystem functioning relationships and the restoration of degraded plantations.

“…The amount of light reaching the understory is one of the most important limiting factors affecting the species of understory plants (Kirby, 1988;Van Calster et al, 2008;Márialigeti et al, 2016;Shi et al, 2021), which determines the coverage, diversity and species composition of undergrowth vegetation. Many studies have shown that improved understory light conditions caused by increased canopy openness can improve plant diversity, especially in the herbaceous layer (Lee et al, 1997;Beaudet and Messier, 2002;Vesala et al, 2005;Ligot et al, 2014;Wang et al, 2017;Ádám et al, 2018;Wan and He, 2020;Shi et al, 2021;Zhang et al, 2021;Su et al, 2022). Theoretically, the effects of light on vegetation are complex because the abundance or diversity of understory vegetation does not necessarily correlate positively with light availability.…”

Section: Effect Of Light and Soil Environment On Understory Species D...mentioning

confidence: 99%

Thinning can increase shrub diversity and decrease herb diversity by regulating light and soil environments

Jian

Zhang

et al. 2022

Tree thinning affects the light environment, which in turn affects the growth and survival of understory vegetation, thus improving species diversity and nutrient cycling, as well as the ecological habitat factors. However, the response of understory vegetation to the thinning intensity and short-time effects in the temperate broadleaf-conifer mixed forest is not completely clear. In this study, four permanent plots with a total area of 4 hm2 were established in a mixed broadleaf-conifer forest in northeast China, with thinning intensities of 20% (light thinning, LT), 35% (medium thinning, MT), 55% (heavy thinning, HT) and the unthinned plot (CK), respectively, in accordance with the basal area. The responses of species diversity to changes in understory vegetation were conducted by a structural equation model (SEM). The results showed that compared with CK, thinning significantly increased the photosynthetically active radiation (PAR) and the light quality (R/FR) (p < 0.05), while decreased the contents of soil total nitrogen (TN), total phosphorous (TP), organic matter (OM), nitrate nitrogen (NN), ammonia nitrogen (AN) and pH. The degree of fragmentation of light factors among the treatment plots gradually decreased as thinning intensity increased. Among all the thinning treatments, PAR and R/FR were found to be the optimal light condition when the forest thinning intensity was 55%. The light condition was found to have a significant negative correlation with soil TN, TP, OM, and AN. While the soil nutrients were positively correlated with herbaceous layer diversity but negatively correlated with shrub layer diversity. The soil nutrients were lost after thinning in a short time and herb diversity decreased, but shrub diversity increased significantly compared with unthinned plots. For the understory vegetation, the species diversity of shrub and herb layer were showed to be more sensitive to soil nutrients than light environment.