Different functional characteristics can explain different dimensions of plant invasion success

The success of invasive plants can be evaluated with different dimensions (Catford et al., 2016). Among them, range size, local abundance, impact on native plant abundance and diversity are four frequently studied non-exclusive (Novoa 2020; Parker 1999). first two quantify species occupancy at scales (regional vs. scale); whereas, the last extent to which a negatively affects aspects communities (plant diversity; Drenovsky 2012; Sofaer 2018). Though there ecological differences among these dimensions, invasiveness has been often estimated by only one or in previous studies non-native invasion (see e.g. Carboni 2016; Küster 2008; Lavoie Schlaepfer 2010;). Species that accumulate high not necessarily widespread regional scale, while locally abundant Catford Pearson Likewise, may have weak impacts surrounding their environment, vice versa Lai 2015; Ricciardi & Cohen, 2007). above evidence suggests exploring mechanisms successful overly simplistic, because they rarely differentiate facilitating scale) those enhancing species' effects communities. Functional characteristics influence how interacts competitors other organisms (e.g. herbivores, mutualistic/pathogenic microbes, etc.; Jacobs Lesmeister, Lin 2015). Thus, given partially attributed its functional (Gallagher 2013). In particular, type colonize habitats strongly depend ability compete, tolerate stress spread CSR-strategic scheme Grime, 1974, 1977). A strong competitive ability, quantified size metrics height, total leaf area seed mass), increase enhance species’ resident displacement neighbouring (Abraham 2009; Maron Vilá, 2001). tolerance stress, dry matter content associated low metabolic rate conservative resource investment strategy, promote expansion long-term persistence wide differing nutrient climatic conditions (Niinemets Valladares, 2006; Reich, 2014). is ruderal an acquisitive such as fecundity large SLA; turn, promotes dispersal, rapid occupation empty niches colonization disturbed (Dawson Given always covary, likely distinct (Drenovsky 2012). For instance, dimension dependent persistence, favour strategies slow growth rate; 2019). another example, dependence competition, like community, benefit from direct mass; So far, no study simultaneously explored (range diversity). recent development comprehensive trait databases provides plenty values for various then allows traits Bjorkman 2018; Bruelheide Cornelissen 1996, 2003; Kattge Kleyer Reich Shiley, 2002; Shipley Vu, 2002). It suggested leaf-related syndromes alone potential reflect basic plants, compared across forms; and, readily available number Pierce 2013; Wright 2004). combination common TRY database important analysis role explaining spatial scales. this study, we aimed address following questions: (a) Do (i.e. diversity) covary? (b) Which plants? Are same equally relevant increased (or abundance) species; what enhanced species? Addressing questions will improve our understanding allow perspective. Moreover, distinctions provide explanations inconsistent findings regarding invaders Novoa 2020). source data quantifying included 1,593 plots field investigations conducted late spring early autumn between 2009 2017 US Europe (R. Pal, R. Filep, D. Nagy, J. Nyulasi, unpubl. data). These were primarily assess severity exotic invasions natural semi-natural broad geographic (between 24°N–50°N), during investigated any sites spotted well-known cheatgrass Bromus tectorum, Jerusalem artichoke Helianthus tuberosus, reed Phragmites australis, narrowleaf plantain Plantago lanceolata, Canada goldenrod Solidago canadensis giant gigantea etc.). We avoided areas adjacent roads trails) might frequented people ensure disturbance level, since human mask interactions significantly affect outcome (Skultety Matthews, 2017). Quadrats 1 4 m2 used perform surveys composition percent cover all species. Across plots, richness averaged 5 (ranging 0 39), 18% 0% 100%). To avoid over-representation particular sites, plot standardized equal-size m2) each nearby coordinates (rounded decimal places) was produce 284 unique (129 155 European sites; Figure 1). Based Köppen–Geiger climate classification current zones (http://koeppen-geiger.vu-wien.ac.at/shifts.htm), mostly located temperate lowland alpine regions had humidity warm summers. few mid western US, steppe region arid, cold details S1). All assigned status according Global Naturalized Alien Flora (GloNAF) (van Kleunen Four categories identified: both Europe; (c) but US; (d) Europe. As result, 636 identified dataset; which, 96 exclusively 28 512 ranges. calculated: (impact relative occurrence frequency focal based equal-sized grid cells occupied range, projected records Biodiversity Information Facility (GBIF; https://www.gbif.org/; see Note S1–S3). calculated median it occurred. loss due 1% [i.e. opposite coefficient log-linear regression Shannon–Wiener index) containing species]. After removing coefficients models insignificant R2 values, obtained 63 83 estimates respectively S4). eight measured [leaf carbon (LCC), nitrogen (LNC), carbon/nitrogen ratio (C:N), weight (LDW), fresh (LFW), per (LDMC), (LA) SLA] (https://www.try-db.org/; request ID 5836). lists datasets presented Table S1. Morphological traits, (quantified LDW LA) SLA, correlate photosynthetic capacity potentially (Díaz Heberling Fridley, Chemical LNC, LCC, C:N, plus LDMC (an indicator tissue density), activity, palatability decomposability. Specifically, content, density correspond rate, preference herbivores fast decomposition rates (Cárdenas 2014; Krebs 2011; Kurokawa 2010). addition, LNC also correlated economics: SLA LNC) corresponds extreme 2019; Díaz compiled dataset continents. Trait obtained, interested According accepted standards, C:N equal LCC/LNC. missing using if available. Similarly, equals LDW/LFW LA/LDW, LDW, LFW, LDMC, LA supplemented correlations traits. LFW calculating excluded further analyses. extracted North America 51 least value. Europe, 19 ranges, ranges value If represent This approach difference trait-success association ignored biogeographic Nonetheless, avoids duplicate dataset, making easier analyses, especially approaches incorporating phylogenetic correlations. 325 final consisted 395 species, having 153 seven LA). Our larger proportion versus non-invasive GloNAF (36% 8%), indicating (Figure S2a). result fact are, perhaps, more found when ones. some economically families Iridaceae, Crassulaceae, Papaveraceae, Myrtaceae Liliaceae etc.), grown crops ornamental seemed under-represented S2b,c). See detailed sampling bias evaluations S5. whether other, formed significance principal component (PCA) function ‘prcomp’ (R Core Team, Parallel determine principle components needed retained ‘paran’ (Dinno, explore success, general linear (LMs) ‘lm’ LMs pair-wise associations plants. Variables log-transformed linearity reduce variance heterogeneity necessary. analyses associations, variables mean standard deviation comparison model pairs dimensions. Additionally, assessed signals variables, including relatedness van 2010; Godoy 2011 Following protocol Qian Jin (2016), functions ‘S.PhyloMaker’ ‘ggtree’ tree S3) tested strength ‘Phylosig’ (Revell, Yu Then, generalized square (PGLS) after accounting ‘phylolm’ (Ho Ane, Again, transformations performed linearity, comparisons Occupancy 2a), indicates being scale However, positive correlation 2b), stronger cause greater reduction diversity. occupancy/abundance neutral slightly 2c,e); negative 2d,f), parallel analysis, three PCA should retained, so multidimensional space explains 73.5% 3; S3). PC1 positively (LCC; S4), suggesting higher herbivores. PC2 (LDW; smaller leaves thus, exhibit weaker light. PC3 (LDMC) carbon-nitrogen acted conservatism lower rate. 4). association. (t = 3.53, p < 0.001) 2.49, 0.013), LCC −2.59, 0.010) −2.36, 0.019; 4a; S5). scale. marginally significant −1.71, 0.089) −1.66, 0.098; 4b; S5), lead 2.68, 0.010), 2.46, 0.017) 1.78, 0.081), −1.78, 0.082) −1.79, 0.081; 4c; S6). light strategy abundance. diversity, trend increasing 1.73, 0.091) decreasing −1.88, 0.066), allowed 4d; tougher, slower-decomposing incur Significant detected (Pagel's λ 0.320, 0.022), (Blomberg's K 0.060, 0.046; Pagel's 0.990, 0.001), 0.790, 0.030, 0.016)] S7), closely related similar SLA. PGLS Blomberg's conducted, close zero, very signals. Since prominent out 11 produced results LMs, Tables S5 S6. global occurrences measures field, relationships success. indeed 5). ‘ideal weeds’ conventional sense (Pyšek Richardson, 2007); possessed sizes r-strategists (also known opportunists; Pianka, 1970); preferred Invaders abundances functionally resembled usually thrive stressful low-disturbance (Davis 2000; Fynn 2005). Generally, would expect accumulation decreased Hejda revealed 2c–f). reported al. (2018), highly species-specific taking forms linear, asymptotic, sigmoidal exponential probably adopted (competition space/resources, allelopathy plant–soil feedback Enders abundance–impact collinearity multiple pooled together, Cohen (2007). abundance), supported finding lack 2016), former dispersal colonization, latter depends competition Although (R2 0.263, 0.001; better explain rather than 4c,d). effect composition: invader could largely dominant competitor against Byun Emery Gross, contrast, invaded community (Hejda 2009). covary adaptive composition. covariances weak, extents, highlighting necessity separately Interestingly, Evidence showed nitrogen-poor less generalist nitrogen-rich (Kurokawa 2010); attacked specialist (Bossdorf 2004; attractiveness prerequisite Unlike multivariate flora 2013, (LA), strongest explanatory power over variations (LCC) (LNC) LA, 3). fact, does simply slower acquisition thus believed key reflected proposed facilitate play crucial expected, exerted seem possess 4c). attributes consumption utilization) 2011). did associate (indirectly study; 4a,b,d). understandable resources, many them disturbances changes (Guisan Thuiller, 2005; Valéry utilization advantageous size-dependent systems niches, niche occupation, short life cycle, helping gain advantage MacDougall why observed unexpectedly lacked importance suggest process influences even small SLA) dominating (Fynn Kyle Leishman, 4b,d). (2019) capture persist longer levels. supplementary trait-abundance confirmed similarity invading (Note S6, S4, S8), supporting Li (2015). propose possible explanations. First, limiting hypothesis, majority dramatic (MacAuthur Levins, 1967). Second, decomposability litter accumulation, noxious invaders, medusahead Taeniatherum caput-medusae, ripgut brome diandrus cattail (Typha × glauca; Freyman, Mariotte 2017; Molinari D'Antonio, 2014), severe incurred regeneration altering physical, chemical microbial properties (Chen Stinson 2006). characteristics. There category where met expectation weeds’, categories, typically considered hindrances invasion. shows inconsistencies affecting partly arise confusion ‘invasion success’ defined. While emphasized within context altered environmental conditions, regimes socioeconomic Cronin Daehler, Otfinowski Kenkel, 2013 necessary make explicit, before trying uncover underlying mechanisms. Ignoring apparent confusing conclusions about reasons major challenge, critically defining distinguishing acquire amount robust statistical quantification respect Luckily, vegetation [see Index Vegetation-Plot Databases (GIVD; http://www.givd.info/)], able include future studies. worth expanding mass, stem etc.) order project funded National Natural Science Foundation China (NSFC 31700450; H.L.), People Programme (Marie Curie Actions) Union's Seventh Framework (FP7/2007-2013) under REA grant 300639 (R.W.P.) Fulbright Commission (R.W.P.). authors thank Judit David U. Nagy Rita Filep help Michael Kleyer, Peter Johannes Cornelissen, Andrew Siefert, Evan Weiher, Bill Shipley, Daniel Laughlin, Joseph Craine, Frédérique Louault contributors listed S1 sharing leaf-trait information thankful Krystal Weilage proofreading English version manuscript anonymous reviewers constructive comments work. H.L. S.P. conceived idea paper; R.W.P. provided Ü.N., M.B. B.E.L.C. data. wrote draft. contributed substantially revision paper gave approval publication. peer review history article https://publons.com/publon/10.1111/1365-2745.13575. Dryad Digital Repository https://doi.org/10.5061/dryad.tmpg4f4xd (Liao List Please note: publisher responsible functionality supplied authors. Any queries (other content) directed corresponding author article.