Functional segregation of resource-use strategies of native and invasive plants across Mediterranean biome communities

Abstract

Functional segregation among species in a community depends on their mean trait values (i.e. functional distinctiveness), and the range of trait attributes exhibited by each species (i.e. functional diversity). Previous evidence suggests that invasive plants tend to display traits related to a more acquisitive resource-use strategy than natives. However, the contribution of intraspecific trait variation to functional diversity has received little attention in community ecology, and might provide interesting information about community processes. In this study, we used eight plant traits related to carbon and nutrient acquisition of coexisting dominant native and invasive plants in eight communities across the Mediterranean-climate biome to determine sources of functional segregation between native and invasive species. We found three major axes of functional variation, related to leaf economics, resource-use efficiency, and plant height. Invasive species across communities had leaf traits related to an acquisitive resource-use strategy in contrast to native species, whereas differences in the second and third principal components were community dependent. Invasive species were more functionally 2 diverse than native species across the dataset and in four out of the eight communities. Intraspecific variance accounted for 11-27% of total trait variation and was on average greater in invasive species, and especially important in the axis related to resource use efficiency. These results, although dependent on the trait and community considered, offer interesting insights to the sources of functional trait diversity of native and invasive species within communities, indicating that intraspecific variation might not be equally distributed between native and invasive species.

Multi‐trait genetic variation in resource‐use strategies and phenotypic plasticity correlates with local climate across the range of a Mediterranean oak (Quercus faginea)

“…Evidence of such variation in resource‐use strategies or trait syndromes has been found at the inter‐specific level across biomes and ecosystems (Díaz et al ., 2016; Bruelheide et al ., 2018; Rueda et al ., 2018). Other studies have, however, failed to find patterns of trait covariation consistent with a growth–survival trade‐off (Wright & Sutton‐Grier, 2012; Laforest‐Lapointe et al ., 2014; Vellend et al ., 2014; Mason & Donovan, 2015; Niinemets, 2015; Messier et al ., 2017; Galán Díaz et al ., 2021). Some possible biological and experimental reasons for the contrasting outcomes of empirical tests of the ‘worldwide ‘fast–slow’ plant economics spectrum’ are as follows: that different organizational levels (Anderegg et al ., 2018), life forms (Schulze et al ., 1998; Funk et al ., 2017) and leaf habits (Hikosaka et al ., 2021) show different trends in trait coordination; that trait coordination depends upon the studied environmental gradient (Anderegg et al ., 2021; Westerband et al ., 2021), and biome (Ramírez‐Valiente & Cavender‐Bares, 2017); and that different strategies found in natural populations are the result of both genetic and plastic variation (Gimeno et al ., 2009), which influence trait coordination in different ways and the assessment of which requires different experimental approaches.…”

Functional assembly of grassland plant species in native communities in Spain and recipient communities in California

“…In Spain, functional differences between colonizer species and other coexisting species did not change along the resource availability gradient except for SLA, with colonizers being more acquisitive along the gradient but particularly in the low‐resource end. In California, functional trait composition related to different aspects of plant strategies differed for natives and colonizers at both ends of the gradient (Galán Díaz, de la Riva, Funk, & Vilà, 2021; Hulme & Bernard‐Verdier, 2018). Particularly, resource uptake strategies (i.e.…”

“…A current challenge in the study of biological invasions is to understand the role of exotic species in community assembly to prevent them from threatening native species and changing the functional structure of the recipient communities (Gallien & Carboni, 2017; Hulme & Bernard‐Verdier, 2018). To address this question, most studies have compared the functional differences between exotic species and native species in communities of the introduced range (Funk et al, 2017; Galán Díaz, de la Riva, Funk, & Vilà, 2021; Henn et al, 2019). These approaches are useful to suggest differences in the use of resources which might drive invasion success or impact.…”

“…Also, plant species adapted to less favourable environments, such as dry habitats, may show contrasting resource uptake strategies due to opportunistic behaviour with respect to water and nutrient use efficiency (de la Riva et al, 2021; Querejeta et al, 2018). In fact, contrasting functional strategies have been shown to promote invasion of Mediterranean arid communities, where exotic species display contrasting life‐history strategies and traits related to resource use (de la Riva et al, 2019; Galán Díaz, de la Riva, Funk, & Vilà, 2021).…”

The Functional Structure of Tropical Plant Communities and Soil Properties Enhance Ecosystem Functioning and Multifunctionality in Different Ecosystems in Ghana

“…Moderates a trade-off between plants' rate of seed production per unit mass invested in reproduction and the mass of each offspring [67] Whole plant Plant height Phg m Reflects a species ability to utilise light and above the ground competition [68,69] SLA was calculated as leaf area divided by the leaf dry mass, while the SDMC was calculated by dividing the oven-dry weight of the stem by the fresh weight. Leaf chemical traits, including carbon, nitrogen and isotopic carbon (δ 13 C), were analysed at the Centre for Stable Isotope Research and Analysis (George August Universität, Göttingen, Germany).…”