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Spartina anglica is an invasive perennial marsh grass causing significant negative impacts on tidal flat ecosystem. There have been only a few studies focusing on the patch structure of S. anglica according to size and its effects on macrofauna. A field experiment was conducted to identify effects of S. anglica patches where they have been introduced no later than 5 years after invasion occurred on macrofauna assemblages. The survey area was divided into two sections according to vegetation: (1) Suaeda japonica vegetation from 0 to 60 m away from the embankment, and (2) bare mudflat from 60 to 90 m away from the embankment. The patch sizes of S. anglica were categorized into small (1–4 m2), medium (5–11 m2), and large (13–40 m2) in area with four replicates for each section. The biomass ratio of the belowground and aboveground in the small size patch of S. anglica was significantly higher than those in the medium and large size patch of S. anglica. It indicated that more resource was allocated to rhizomes in small size patch with short invasion history (1 ~ 2 years). After S. anglica invaded, macrofauna richness (70%), Shannon-Wiener diversity (80%), and density (67%) were decreased. However, infaunal deposit-feeding polychaete Perinereis linea and epifaunal gastropods Batillaria cumingi and Lactiforis takii increased by S. anglica. Ordination of macroinvertebrate assemblages separated the habitat with S. anglica invasion from the adjacent uninvaded tidal flat and Suaeda japonica habitats. This study offers a significant insight into early invasion strategies of an aggressive plant invader, S. anglica for management of coastal wetlands and its impacts on macrofaunal assemblages.

As Earth's climate has varied strongly through geological time, studying the impacts of past climate change on biodiversity helps to understand the risks from future climate change. However, it remains unclear how paleo-climate shapes spatial variation in biodiversity. Here, we assessed the influence of Quaternary climate change on spatial dissimilarity in taxonomic, phylogenetic, and functional composition among neighboring 200-kilometer cells (beta-diversity) for angiosperm trees worldwide. We found that larger glacial-interglacial temperature change was strongly associated with lower spatial turnover (species replacements) and higher nestedness (rich-ness changes) components of beta-diversity across all three biodiversity facets. Moreover, phylogenetic and functional turnover was lower and nestedness higher than random expectations based on taxonomic beta -di-versity in regions that experienced large temperature change, reflecting phylogenetically and functionally se-lective processes in species replacement, extinction, and colonization during glacial-interglacial oscillations. Our results suggest that future human-driven climate change could cause local homogenization and reduction in taxonomic, phylogenetic, and functional diversity of angiosperm trees worldwide. W.-B.X. and A.O. acknowledge support from the Aarhus University Research Foundation (AUFF) Starting Grant (AUFF-F-2018-7-8). J.-C.S. acknowledges support from the Danish Council for Independent Research|Natural Sciences (grant 6108-00078B) to the TREECHANGE Project. J.-C.S. also considers this work a contribution to the Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) funded by Danish National Research Foundation (grant DNRF173) and the VILLUM Investigator project “Biodiversity Dynamics in a Changing World” funded by VILLUM FONDEN (grant 16549). W.L.E. was supported by the VILLUM FONDEN (grant 00025354). M.A. was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery grants program. C.B. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2022R1A2C1003504). A.G.G. was supported by the ANID PIA/BASAL (grant FB210006) and FONDECYT (grant 1200468). R.E.O. was supported by the German Research Foundation to German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig (DFG-FZT 118, 202548816). J.Pe. was supported by the Fundación Ramón Areces project (CIVP20A6621) and Spanish Government project (PID2019-110521GB-I00). J.Pi. was supported by the Estonian Research Council Grants (PUT1355, PRG 1405) and Mobilitas Pluss (MOBERC11). V.D.P. was supported by the National Council of Scientific and Technological Development (CNPq) of Brazil (grant 307689/2014-0).

Safeguarding Earth?s tree diversity is a conservation priority due to the importance of trees for biodiversity and ecosystem functions and services such as carbon sequestration. Here, we improve the foundation for effective conservation of global tree diversity by analyzing a recently developed database of tree species covering 46,752 species. We quantify range protection and anthropogenic pressures for each species and develop conservation priorities across taxonomic, phylogenetic, and functional diversity dimensions. We also assess the effectiveness of several influential proposed conservation prioritization frameworks to protect the top 17% and top 50% of tree priority areas. We find that an average of 50.2% of a tree species? range occurs in 110-km grid cells without any protected areas (PAs), with 6,377 small-range tree species fully unprotected, and that 83% of tree species experience nonnegligible human pressure across their range on average. Protecting highpriority areas for the top 17% and 50% priority thresholds would increase the average protected proportion of each tree species? range to 65.5% and 82.6%, respectively, leaving many fewer species (2,151 and 2,010) completely unprotected. The priority areas identified for trees match well to the Global 200 Ecoregions framework, revealing that priority areas for trees would in large part also optimize protection for terrestrial biodiversity overall. Based on range estimates for >46,000 tree species, our findings show that a large proportion of tree species receive limited protection by current PAs and are under substantial human pressure. Improved protection of biodiversity overall would also strongly benefit global tree diversity. Made available in DSpace on 2022-06-21T15:23:55Z (GMT). No. of bitstreams: 1 Guo-et-al.-2022-PNAS-High-exposure-of-global-tree-diversity-to-human-pressure.pdf: 2523289 bytes, checksum: 245be3df3fb487ed152d25bf50f4e984 (MD5) Previous issue date: 2022 Proceedings of the National Academy of Sciences of the United States of America.

Understanding how plant communities reassemble is particularly relevant when invaders are part of the species pool and can compromise restoration or conservation goals. If initial species composition has a lasting impact on community dynamics, it may be possible to enhance biotic resistance to invasion, particularly through diversity effects, by manipulating early community composition. Diversity effects have been investigated much less in wetlands than in uplands. We conducted a large plant community restoration experiment in a freshwater wetland to investigate species and functional diversity effects on biotic resistance to invasion during early community assembly. The wetland was under propagule pressure mostly from Phragmites australis (common reed), but all species not sown in this experiment that established in the plots were treated as ‘invaders’, whether exotic or native. We used a two‐step model selection approach and a diversity‐interaction model framework to test hypotheses about the contribution to invasion success of abiotic conditions, species richness, as well as functional group richness, identity and pairwise interactions, providing a rare test of diversity effects against multiple invaders in wetlands. In all, 20 species invaded the plots. They were grouped for analysis to evaluate the overall resistance of resident communities. The three main invaders, P. australis and two native taxa (Salix spp., Populus deltoides), were also analysed separately. Diversity‐interaction models revealed invader‐specific responses. Functional group identity determined resistance to P. australis, whereas pairwise interactions between functional groups explained resistance to Salix spp. Both effects were retained when grouping all invaders. Resistance to P. deltoides was determined by abiotic conditions. The contribution of specific functional groups varied with invader. Annuals and clonal perennials explained resistance to P. australis, suggesting priority and limiting similarity effects. Interactions, when significant, mostly included fast‐growing annuals. When considering all invaders, identity effects were detected for all functional groups. Synthesis. Diversity effects on invasion resistance vary with invaders in early assembly of restored wetland communities. Restoring functionally diverse communities provides resistance against multiple invaders. Consistent responses between this field experiment and previous pot experiments with the same species suggest that results are robust enough to inform management.

Simulations of the land surface carbon cycle typically compress functional diversity into a small set of plant functional types (PFT), with parameters defined by the average value of measurements of functional traits. In most earth system models, all wild plant life is represented by between five and 14 PFTs and a typical grid cell (≈100 × 100 km) may contain a single PFT. Model logic applied to this coarse representation of ecological functional diversity provides a reasonable proxy for the carbon cycle, but does not capture the non-linear influence of functional traits on productivity. Here we show through simulations using the Energy Exascale Land Surface Model in 15 diverse terrestrial landscapes, that better accounting for functional diversity markedly alters predicted total carbon uptake. The shift in carbon uptake is as great as 30% and 10% in boreal and tropical regions, respectively, when compared to a single PFT parameterized with the trait means. The traits that best predict gross primary production vary based on vegetation phenology, which broadly determines where traits fall within the global distribution. Carbon uptake is more closely associated with specific leaf area for evergreen PFTs and the leaf carbon to nitrogen ratio in deciduous PFTs.

Sicyos angulatus is a serious threat to riverine ecosystem functions and services worldwide. Here, we studied the effect of species identity and diversity on biotic resistance to S. angulatus under two different soil nutrient levels (unfertilized vs. fertilized). Soil nutrient levels showed no significant effect on invasion by S. angulatus in the control treatment, where intervention by native plants was absent. Species identity of native plants and its interaction with soil nutrient levels had a significant effect on biotic resistance to S. angulatus. For instance, Pennisetum alopecuroides and Lespedeza cuneata best resisted invasion in fertilized soil, whereas Lespedeza bicolor and Lactuca indica best resisted invasion in unfertilized soil. In addition, a mixture of four plant species resisted invasion equally as well as the monoculture of a species in unfertilized soil, whereas the mixed treatment resisted invasion much better in fertilized soil compared with unfertilized soil. Structural equation modeling revealed that species identity and diversity as well as fertilizer application significantly influenced biotic resistance to S. angulatus invasion, while soil nutrients did not influence invasion success directly. Based on these results, we strongly suggest sowing seed mixtures of various species after eradicating S. angulatus plants to prevent re-invasion. Overall, these results demonstrate how native plants rely on resource availability to resist colonization by an invasive plant, such as S. angulatus. This information can be used for the development of improved guidelines for plant restoration and invasive species control.

Plant functional traits can predict community assembly and ecosystem functioning and are thus widely used in global models of vegetation dynamics and land–climate feedbacks. Still, we lack a global understanding of how land and climate affect plant traits. A previous global analysis of six traits observed two main axes of variation: (1) size variation at the organ and plant level and (2) leaf economics balancing leaf persistence against plant growth potential. The orthogonality of these two axes suggests they are differently influenced by environmental drivers. We find that these axes persist in a global dataset of 17 traits across more than 20,000 species. We find a dominant joint effect of climate and soil on trait variation. Additional independent climate effects are also observed across most traits, whereas independent soil effects are almost exclusively observed for economics traits. Variation in size traits correlates well with a latitudinal gradient related to water or energy limitation. In contrast, variation in economics traits is better explained by interactions of climate with soil fertility. These findings have the potential to improve our understanding of biodiversity patterns and our predictions of climate change impacts on biogeochemical cycles., Nature Ecology & Evolution, 6 (1), ISSN:2397-334X

21 Pág. Instituto de Ciencias Forestales (ICIFOR), Ecological theory is built on trade-offs, where trait differences among species evolved as adaptations to different environments. Trade-offs are often assumed to be bidirectional, where opposite ends of a gradient in trait values confer advantages in different environments. However, unidirectional benefits could be widespread if extreme trait values confer advantages at one end of an environmental gradient, whereas a wide range of trait values are equally beneficial at the other end. Here, we show that root traits explain species occurrences along broad gradients of temperature and water availability, but model predictions only resembled trade-offs in two out of 24 models. Forest species with low specific root length and high root tissue density (RTD) were more likely to occur in warm climates but species with high specific root length and low RTD were more likely to occur in cold climates. Unidirectional benefits were more prevalent than trade-offs: for example, species with large-diameter roots and high RTD were more commonly associated with dry climates, but species with the opposite trait values were not associated with wet climates. Directional selection for traits consistently occurred in cold or dry climates, whereas a diversity of root trait values were equally viable in warm or wet climates. Explicit integration of unidirectional benefits into ecological theory is needed to advance our understanding of the consequences of trait variation on species responses to environmental change., sPlot was initiated by sDiv and funded by the German Research Foundation (FZT 118) and is now a platform of iDiv. The sRoot workshops and L.M. were also supported by NWO-Vidi grant 864.14.006. C.M.I. and the Fine-Root Ecology Database were supported by the Biological and Environmental Research program in the US Department of Energy’s Office of Science. J.B. was supported by Deutsche Forschungsgemeinschaft (DFG) project 432975993. N.R.G.-R. thanks the Dorothea Schlözer Postdoctoral Programme of the Georg-August-Universität.

Understanding drivers of success for alien species can inform on potential future invasions. Recent conceptual advances highlight that species may achieve invasiveness via performance along at least three distinct dimensions: 1) local abundance, 2) geographic range size, and 3) habitat breadth in naturalized distributions. Associations among these dimensions and the factors that determine success in each have yet to be assessed at large geographic scales. Here, we combine data from over one million vegetation plots covering the extent of Europe and its habitat diversity with databases on species' distributions, traits, and historical origins to provide a comprehensive assessment of invasiveness dimensions for the European alien seed plant flora. Invasiveness dimensions are linked in alien distributions, leading to a continuum from overall poor invaders to super invaders - abundant, widespread aliens that invade diverse habitats. This pattern echoes relationships among analogous dimensions measured for native European species. Success along invasiveness dimensions was associated with details of alien species' introduction histories: earlier introduction dates were positively associated with all three dimensions, and consistent with theory-based expectations, species originating from other continents, particularly acquisitive growth strategists, were among the most successful invaders in Europe. Despite general correlations among invasiveness dimensions, we identified habitats and traits associated with atypical patterns of success in only one or two dimensions - for example, the role of disturbed habitats in facilitating widespread specialists. We conclude that considering invasiveness within a multidimensional framework can provide insights into invasion processes while also informing general understanding of the dynamics of species distributions., Deutsche Forschungsgemeinschaft (264740629) Grantová Agentura České Republiky (19-28491X) Grantová Agentura České Republiky (19-28807X) Grantová Agentura České Republiky (RVO 67985939) Austrian Science Fund (I 2086 - B29) Bundesministerium für Bildung und Forschung (01LC1807A) Eusko Jaurlaritza (IT299-10) National Research Foundation of Korea (2018R1C1B6005351) University of Latvia (AAp2016/B041//Zd2016/AZ03) Villum Fonden (16549)

Background To address the lack of evidence supporting invasion by three invasive plant species (Imperata cylindrica, Lantana camara, and Chromolaena odorata) in tropical ecosystems, we compared the ecophysiological and leaf anatomical traits of these three invasive alien species with those of species native to Sempu Island, Indonesia. Data on four plant traits were obtained from the TRY Plant Trait Database, and leaf anatomical traits were measured using transverse leaf sections. Results Two ecophysiological traits including specific leaf area (SLA) and seed dry weight showed significant association with plant invasion in the Sempu Island Nature Reserve. Invasive species showed higher SLA and lower seed dry weight than non-invasive species. Moreover, invasive species showed superior leaf anatomical traits including sclerenchymatous tissue thickness, vascular bundle area, chlorophyll content, and bundle sheath area. Principal component analysis (PCA) showed that leaf anatomical traits strongly influenced with cumulative variances (100% in grass and 88.92% in shrubs), where I. cylindrica and C. odorata outperformed non-invasive species in these traits. Conclusions These data suggest that the traits studied are important for plant invasiveness since ecophysiological traits influence of light capture, plant growth, and reproduction while leaf anatomical traits affect herbivory, photosynthetic assimilate transport, and photosynthetic activity.

BackgroundAmbrosia trifidais a highly invasive annual plant, but effective control methods have not been proposed. Among various eradication methods, cutting is a simple measure to control invasive plants, and sowing seeds of native plants may effectively increase biotic resistance to invasion. In this study, we conducted a field experiment with two treatments: cutting and sowing seeds of six native or naturalized plants.ResultsWe found a significantly lowerA. trifidaabundance after cutting than in the control (77% decrease). Sowing seeds of native species did not provide any additional benefit for the control ofA. trifida, but increased the importance values and diversity of other native vegetation. The abundance ofA. trifidawas negatively correlated with that of other plant taxa based on plant cover, biomass, and density. However, biotic resistance of sown plants was not effective to control invasion becauseA. trifidawas so competitive.ConclusionsWe concluded that cutting is an effective measure to controlAmbrosia trifidawhile sowing seeds of native plants can increase native plant diversity.

Trees are of vital importance for ecosystem functioning and services at local to global scales, yet we still lack a detailed overview of the global patterns of tree diversity and the underlying drivers, particularly the imprint of paleoclimate. Here, we present the high-resolution (110 km) worldwide mapping of tree species richness, functional and phylogenetic diversities based on ∼7 million quality-assessed occurrences for 46,752 tree species (80.5% of the estimated total number of tree species), and subsequent assessments of the influence of paleo-climate legacies on these patterns. All three tree diversity dimensions exhibited the expected latitudinal decline. Contemporary climate emerged as the strongest driver of all diversity patterns, with Pleistocene and deeper-time (>107 years) paleoclimate as important co-determinants, and, notably, with past cold and drought stress being linked to reduced current diversity. These findings demonstrate that tree diversity is affected by paleoclimate millions of years back in time and highlight the potential for tree diversity losses from future climate change.

Although trees are key to ecosystem functioning, many forests and tree species across the globe face strong threats. Preserving areas of high biodiversity is a core priority for conservation; however, different dimensions of biodiversity and varied conservation targets make it difficult to respond effectively to this challenge. Here, we (i) identify priority areas for global tree conservation using comprehensive coverage of tree diversity based on taxonomy, phylogeny, and functional traits; and (ii) compare these findings to existing protected areas and global biodiversity conservation frameworks. We find that ca. 51% of the top-priority areas for tree biodiversity are located in current protected areas. The remaining half top-priority areas are subject to moderate to high human pressures, indicating conservation actions are needed to mitigate these human impacts. Our findings emphasize the effectiveness of using tree conservation priority areas for future global conservation planning.

The effect of native plant restoration on invasion by giant ragweed (Ambrosia trifida), an invasive species, is currently unknown. We hypothesized that (1) functional group identity would be a good predictor of biotic resistance to A. trifida, and (2) mixtures of species would be more resistant to invasion than monocultures. Using seven functional traits, 37 native and non-native plants were divided into three functional groups that differed primarily in longevity and woodiness. We conducted a competition experiment using an additive competition design with A. trifida and monocultures or mixtures of 14 species. Biotic resistance was evaluated by calculating a relative competition index (RCIavg) based on the average performance of A. trifida in treatments compared with that in control. In monocultures, RCIavg of resident plants did not significantly differ among the three functional groups or within each functional group. The highest RCIavg (40%) was observed for some fast-growing annuals (FG1) such as Zea mays and Secale cereal, which were strong competitors. RCIavg of resident plants was not significantly greater in mixtures than in monocultures. Taken together, the results show that plant diversity did not control invasion by A. trifida and that giant ragweed invasion cannot be well controlled by biotic resistance.

International audience; The origins of agriculture were key events in human history, during which people came to depend for their food on small numbers of animal and plant species. However, the biological traits determining which species were domesticated for food provision, and which were not, are unclear. Here, we investigate the phylogenetic distribution of livestock and crops, and compare their phenotypic traits with those of wild species. Our results indicate that phylogenetic clustering is modest for crop species but more intense for livestock. Domesticated species explore a reduced portion of the phenotypic space occupied by their wild counterparts and have particular traits in common. For example, herbaceous crops are globally characterized by traits including high leaf nitrogen concentration and tall canopies, which make them fast-growing species and proficient competitors. Livestock species are relatively large mammals with low basal metabolic rates, which indicate moderate to slow life histories. Our study therefore reveals ecological differences in domestication potential between plants and mammals. Domesticated plants belong to clades with traits that are advantageous in intensively managed high-resource habitats, whereas domesticated mammals are from clades adapted to moderately productive environments. Combining comparative phylogenetic methods with ecologically relevant traits has proven useful to unravel the causes and consequences of domestication.

Despite debates on the real impact of plant invasion on native biodiversity, there remain many situations where exotic invasive plants must be managed and habitats restored. Restoration practices that build on plant community assembly principles could be useful to delay or prevent re-invasion after control, but there are still few syntheses of the biodiversity theory, ecological mechanisms and experimental evidence relevant to invasive plant management, possibly delaying applications. To provide such a synthesis, we review current knowledge on three key determinants of invasion success: biotic resistance, abiotic constraints, and propagule pressure. We elaborate on the ecological mechanisms at play for each determinant and emphasize, using case studies, their relevance for invasive plant management and ecological restoration. We find evidence that restoring a plant cover can enhance invasion resistance, but the challenge for both research and field applications is to understand how multiple determinants interact in relation to species traits in the fields. Failure to recognize these interactions and their effect on community assembly processes may explain some of the mixed species responses observed. While we need control and restoration case studies with local species at different sites, the development of a coherent, dynamic and adaptive framework around biotic/ecological resistance will have to go beyond the idiosyncrasy of the many species and systems being tested. Emphasizing the functional diversity of the restored community seems a promising approach when facing potentially multiple invaders and/or fluctuating abiotic conditions.

Additional file 1: Table S1. List of species found in the experimental plots.

Physiological responses of plants to elevated carbon dioxide (CO2) and nitrogen (N) availability are ecologically important because of increased atmospheric CO2 concentrations and N enrichment in many ecosystems. Here, the effects of N availability on the responses of six wetland plant species to elevated CO2 levels are examined in terms of growth and root exudation. Six species of emergent plant species typically found in marshes were incubated under two levels of CO2 (370 and 740 ppm) and two levels of N (0 and 8.8 mg N L−1). Elevated CO2 did not affect shoot biomass, root biomass, and height significantly, regardless of N levels. The C/N ratio of plant species increased in response to elevated CO2 levels, but this effect varied by species. All species released higher amounts of dissolved organic carbon under elevated CO2 compared with ambient air conditions. This response was limited under low soil N concentrations. By contrast, phenolic content increased significantly with elevated CO2 under low-N treatment. The findings suggest that elevated CO2 is not responsible for biomass accumulation of emergent wetland plant species, but does elicit changes in the quantity and quality of root exudates, which are, in turn, dependent on N availability to plant species.

Aim: Plant trait databases often contain traits that are correlated, but for whom direct (undirected statistical dependency) and indirect (mediated by other traits) connections may be confounded. The confounding of correlation and connection hinders our understanding of plant strategies, and how these vary among growth forms and climate zones. We identified the direct and indirect connections across plant traits relevant to competition, resource acquisition and reproductive strategies using a global database and explored whether connections within and between traits from different tissue types vary across climates and growth forms. Location: Global. Major taxa studied: Plants. Time period: Present. Methods: We used probabilistic graphical models and a database of 10 plant traits (leaf area, specific leaf area, mass- and area-based leaf nitrogen and phosphorous content, leaf life span, plant height, stem specific density and seed mass) with 16,281 records to describe direct and indirect connections across woody and non-woody plants across tropical, temperate, arid, cold and polar regions. Results: Trait networks based on direct connections are sparser than those based on correlations. Land plants had high connectivity across traits within and between tissue types; leaf life span and stem specific density shared direct connections with all other traits. For both growth forms, two groups of traits form modules of more highly connected traits; one related to resource acquisition, the other to plant architecture and reproduction. Woody species had higher trait network modularity in polar compared to temperate and tropical climates, while non-woody species did not show significant differences in modularity across climate regions. Main conclusions: Plant traits are highly connected both within and across tissue types, yet traits segregate into persistent modules of traits. Variation in the modularity of trait networks suggests that trait connectivity is shaped by prevailing environmental conditions and demonstrates that plants of different growth forms use alternative strategies to cope with local conditions. © 2019 John Wiley and Sons Ltd

Allelopathy has been suggested as one potential mechanism facilitating the successful colonisation and expansion of invasive plants. The impacts of the ongoing elevation in atmospheric carbon dioxide (CO2) on the production of allelochemicals by invasive species are of great importance because they play a potential role in promoting biological invasion at the global scale. Common ragweed (Ambrosia artemisiifolia var. elatior), one of the most notorious invasive exotic plant species, was used to assess changes in foliar mono- and sesquiterpene production in response to CO2 elevation (389.12 ± 2.55 vs. 802.08 ± 2.69 ppm). The plant growth of common ragweed significantly increased in elevated CO2. The major monoterpenes in the essential oil extracted from common ragweed leaves were β-myrcene, dl-limonene and 1,3,6-octatriene, and the major sesquiterpenes were β-caryophyllene and germacrene-D. The concentrations of 1,3,6-octatriene (258%) and β-caryophyllene (421%) significantly increased with CO2 elevation. These findings improve our understanding of how allelochemicals in common ragweed respond to CO2 elevation.

Organic carbon stored in coastal wetlands, which comprises the major part of oceanic “blue carbon,” is a subject of growing interest and concern. In this study, organic carbon storage in coastal wetlands and its economic value were estimated using the raw data of 25 studies related to soil carbon storage. Data were collected from three tidal flats (one protected and two developed areas) and two estuarine salt marshes (one protected and one restored area). Bulk density, soil organic matter content, and standing biomass of vegetation were all considered, with Monte Carlo simulation applied to estimate the uncertainty. Mean carbon storage in two salt marshes ranged between 14.6 and 25.5 kg C m−2. Mean carbon storage in tidal flats ranged from 18.2 to 28.6 kg C m−2, with variability possibly related to soil texture. The economic value of stored carbon was estimated by comparison with the price of carbon in the emission trading market. The value of US $6600 ha−1 is ~ 45% of previously estimated ecosystem services from fishery production and water purification functions in coastal areas. Although our study sites do not cover all types of large marine ecosystem, this study highlights the substantial contribution of coastal wetlands as carbon sinks and the importance of conserving these habitats to maximize their ecosystem services.

Flooding regimes are a primary influence on the wetland plant community. Human-induced disturbance often changes the duration and frequency of flooding in wetlands, and has a marked influence on wetland plant composition and viability. Comprehensive studies of the environmental thresholds of wetland plants are required for the development of proper practices for wetland management and restoration after hydrological disturbance. This study provides a quantitative assessment of the establishment, growth, and community shifts in dominance of three emergent plant species (Scirpus tabernaemontani, Typha orientalis, and Zizania latifolia) typical of South Korean wetlands, under five hydrological regimes (waterlogged, low-level standing water, high-level standing water, intensive periodic flooding, and intermittent flooding) over four growing seasons. A mesocosm experiment was conducted in the campus of Seoul National University, South Korea. The number and biomass of shoots of Z. latifolia responded positively to increased water level and flooding frequency, while that of the other plants did not. Zizania latifolia outcompeted S. tabernaemontani and T. orientalis irrespective of hydrological regime. This study suggests that Z. latifolia can outcompete the other two macrophytes in the field. This study will improve our ability to predict the dynamics of wetland vegetation and so facilitate the formulation of wetland management and restoration strategies.

Table S1. Raw data sampling point of soil organic carbon storage per unit areas and source for literature to create Table 1. Table S2 Source of reference for carbon stock in different ecosystem for Fig. 3. (DOCX 27 kb)

Our ability to understand and predict the response of ecosystems to a changing environment depends on quantifying vegetation functional diversity. However, representing this diversity at the global scale is challenging. Typically, in Earth system models, characterization of plant diversity has been limited to grouping related species into plant functional types (PFTs), with all trait variation in a PFT collapsed into a single mean value that is applied globally. Using the largest global plant trait database and state of the art Bayesian modeling, we created fine-grained global maps of plant trait distributions that can be applied to Earth system models. Focusing on a set of plant traits closely coupled to photosynthesis and foliar respiration—specific leaf area (SLA) and dry mass-based concentrations of leaf nitrogen (Nm) and phosphorus (Pm), we characterize how traits vary within and among over 50,000 ∼50×50-km cells across the entire vegetated land surface. We do this in several ways—without defining the PFT of each grid cell and using 4 or 14 PFTs; each model’s predictions are evaluated against out-of-sample data. This endeavor advances prior trait mapping by generating global maps that preserve variability across scales by using modern Bayesian spatial statistical modeling in combination with a database over three times larger than that in previous analyses. Our maps reveal that the most diverse grid cells possess trait variability close to the range of global PFT means., This research was supported as part of the Energy Exascale Earth System Model (E3SM) project, funded by the US Department of Energy, Office of Science, Office of Biological and Environmental Research (Grant DE-SC0012677 to P.B.R. and A.B.). O.K.A. acknowledges the support of the Australian Research Council (CE140100008). This research was also funded by programs from the NSF Long-Term Ecological Research (Grant DEB-1234162) and Long-Term Research in Environmental Biology (Grant DEB-1242531). A.B., F.F., and P.B.R. acknowledge funding from NSF Grant IIS-1563950. P.B.R. also acknowledges support from two University of Minnesota Institute on the Environment discovery grants. This study has been supported by the TRY initiative on plant traits (www.try-db.org). The TRY database is hosted at the Max Planck Institute for Biogeochemistry (Jena, Germany) and supported by DIVERSITAS/Future Earth, the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, and the EU H2020 project BACI (Grant 640176). B.B. acknowledges a Natural Environment Research Council (NERC) independent research fellowship NE/M019160/1. J.P. acknowledges the financial support from the European Research Council Synergy Grant ERC-SyG-2013-610028 IMBALANCE-P, the Spanish Government Grant CGL2013-48074-P, and the Catalan Government Grant SGR 2014-274. B.B.-L. was supported by the Earth System Modeling program of the US Department of Energy, Office of Science, Office of Biological and Environmental Research. K.K. acknowledges the contribution of the Wageningen University and Research Investment theme Resilience for the project Resilient Forest (KB-29-009-003). P.M. acknowledges support from ARC Grant FT110100457 and NERC Grant NE/F002149/1. W.H. acknowledges support from the National Natural Science Foundation of China (Grant 41473068) and the “Light of West China” Program of the Chinese Academy of Sciences.

The origins of agriculture were key events in human history, during which people came to depend for their food on small numbers of animal and plant species. However, the biological traits determining which species were domesticated for food provision, and which were not, are unclear. Here, we investigate the phylogenetic distribution of livestock and crops, and compare their phenotypic traits with those of wild species. Our results indicate that phylogenetic clustering is modest for crop species but more intense for livestock. Domesticated species explore a reduced portion of the phenotypic space occupied by their wild counterparts and have particular traits in common. For example, herbaceous crops are globally characterized by traits including high leaf nitrogen concentration and tall canopies, which make them fast-growing species and proficient competitors. Livestock species are relatively large mammals with low basal metabolic rates, which indicate moderate to slow life histories. Our study therefore reveals ecological differences in domestication potential between plants and mammals. Domesticated plants belong to clades with traits that are advantageous in intensively managed high-resource habitats, whereas domesticated mammals are from clades adapted to moderately productive environments. Combining comparative phylogenetic methods with ecologically relevant traits has proven useful to unravel the causes and consequences of domestication.

Restoring invasion-resistant plant communities is critical for the successful control of invasive plant species. It is based on ecological principles, such as limiting similarity, and the diversity–invasibility hypothesis, which can be used to select optimal combinations of species and determine appropriate plant density for the effective suppression of invasion due to propagule pressure. However, no attempt has been made to combine these factors in a single research framework. Here, we show for the first time the relative importance of all significant factors, including seed density, limiting similarity, diversity effect, and propagule pressure, in the invasion mechanism of Sicyos angulatus, an invasive plant species. Our results suggest that seed density, rarely explored in previous studies, is as important a determinant of invasion success as limiting similarity, diversity effect, and propagule pressure. Thus, the density-mediated mechanism must be given careful consideration for the restoration of strong invasion-resistant native plant communities.

In southern Quebec, Canada, Trifolium species are commonly used as supplement ground cover along roadside of major roads to assist turf recruitment. They often fail to establish particularly near roadside edges. The noxious weed, Ambrosia artemisiifolia, exploits the empty niches. Based on an assumption that heavy metal stress mainly drives plant species shift, we conducted a field experiment to test the emergence of four species near roadside edges along a metal gradient. The test species included a clover ground cover (Trifolium arvense), two candidate ground covers (Lotus corniculatus and Coronilla varia), and the weed (A. artemisiifolia). Two hundred wet-cold stratified seeds of each species were sown in plots (20 × 30 cm), assigned separately for one of four species treatments, replicated three times. We measured final emergence percentage and soil metal contents and analyzed their correlations. T. arvense emergence was negatively correlated with Zn, Pb, and Cu. In contrast, A. artemisiifolia emergence was positively correlated with Zn, Pb, and Cu. The experiment supports the hypothesis that A. artemisiifolia colonization along roadside edges may be attributing to its greater tolerance for Zn, Pb, and Cu than T. arvense. In evaluating the two legume candidates, L. corniculatus was positively correlated with Zn, Pb, and Cu like A. artemisiifolia, while C. varia emergence did not have significant relationship with Pb and Cu. The current finding implies that L. corniculatus can be a good candidate because of its emergence performance and its tolerance to heavy metal, similarly to that of A. artemisiifolia.

Biotic resistance is the ability of species in a community to limit the invasion of other species. However, biotic resistance is not widely used to control invasive plants. Experimental, functional, and modeling approaches were combined to investigate the processes of invasion by Ageratina altissima (white snakeroot), a model invasive species in South Korea. We hypothesized that (1) functional group identity would be a good predictor of biotic resistance to A. altissima, whereas a species identity effect would be redundant within a functional group, and (2) mixtures of species would be more resistant to invasion than monocultures. We classified 37 species of native plants into three functional groups based on seven functional traits. The classification of functional groups was based primarily on differences in life longevity and woodiness. A competition experiment was conducted based on an additive competition design with A. altissima and monocultures or mixtures of resident plants. As an indicator of biotic resistance, we calculated a relative competition index (RCIavg) based on the average performance of A. altissima in a competition treatment compared with that of the control where only seeds of A. altissima were sown. To further explain the effect of diversity, we tested several diversity–interaction models. In monoculture treatments, RCIavg of resident plants was significantly different among functional groups but not within each functional group. Fast-growing annuals (FG1) had the highest RCIavg, suggesting priority effects (niche pre-emption). RCIavg of resident plants was significantly greater in a mixture than in a monoculture. According to the diversity–interaction models, species interaction patterns in mixtures were best described by interactions between functional groups, which implied niche partitioning. Functional group identity and diversity of resident plant communities were good indicators of biotic resistance to invasion by introduced A. altissima, with the underlying mechanisms likely niche pre-emption and niche partitioning. This method has most potential in assisted restoration contexts, where there is a desire to reintroduce natives or boost their population size due to some previous level of degradation.

Biotic resistance is the ability of species in a community to limit the invasion of other species. However, biotic resistance is not widely used to control invasive plants. Experimental, functional, and modeling approaches were combined to investigate the processes of invasion by Ageratina altissima (white snakeroot), a model invasive species in South Korea. We hypothesized that (1) functional group identity would be a good predictor of biotic resistance to A. altissima, whereas a species identity effect would be redundant within a functional group, and (2) mixtures of species would be more resistant to invasion than monocultures. We classified 37 species of native plants into three functional groups based on seven functional traits. The classification of functional groups was based primarily on differences in life longevity and woodiness. A competition experiment was conducted based on an additive competition design with A. altissima and monocultures or mixtures of resident plants. As an indicator of biotic resistance, we calculated a relative competition index (RCI avg) based on the average performance of A. altissima in a competition treatment compared with that of the control where only seeds of A. altissima were sown. To further explain the effect of diversity, we tested several diversity–interaction models. In monoculture treatments, RCI avg of resident plants was significantly different among functional groups but not within each functional group. Fast‐growing annuals (FG1) had the highest RCI avg, suggesting priority effects (niche pre‐emption). RCI avg of resident plants was significantly greater in a mixture than in a monoculture. According to the diversity–interaction models, species interaction patterns in mixtures were best described by interactions between functional groups, which implied niche partitioning. Functional group identity and diversity of resident plant communities were good indicators of biotic resistance to invasion by introduced A. altissima, with the underlying mechanisms likely niche pre‐emption and niche partitioning. This method has most potential in assisted restoration contexts, where there is a desire to reintroduce natives or boost their population size due to some previous level of degradation.

Summary 1. Biotic resistance, the ability of species in a community to limit invasion, is central to our understanding of how communities at risk of invasion assemble after disturbances, but it has yet to translate into guiding principles for the restoration of invasion-resistant plant communities. We combined experimental, functional, and modelling approaches to investigate processes of community assembly contributing to biotic resistance to an introduced lineage of Phragmites australis, a model invasive species in North America. We hypothesized that (i) functional group identity would be a good predictor of biotic resistance to P. australis, while species identity effect would be redundant within functional group (ii) mixtures of species would be more invasion resistant than monocultures. 2. We classi! ed 36 resident wetland plants into four functional groups based on eight functional traits. We conducted two competition experiments based on the additive competition design with P. australis and monocultures or mixtures of wetland plants. As an indicator of biotic resistance, we calculated a relative competition index (RCIavg) based on the average performance of P. australis in competition treatment compared with control. To explain diversity effect further, we partitioned it into selection effect and complementarity effect and tested several diversity‐interaction models. 3. In monoculture treatments, RCIavg of wetland plants was signi! cantly different among functional groups, but not within each functional group. We found the highest RCIavg for fast-growing annuals, suggesting priority effect. 4. RCIavg of wetland plants was signi! cantly greater in mixture than in monoculture mainly due to complementarity‐diversity effect among functional groups. In diversity‐interaction models, species interaction patterns in mixtures were described best by interactions between functional groups when ! tted to RCIavg or biomass, implying niche partitioning. 5. Synthesis. Functional group identity and diversity of resident plant communities are good indicators of biotic resistance to invasion by introduced Phragmites australis, suggesting niche preemption (priority effect) and niche partitioning (diversity effect) as underlying mechanisms. Guiding principles to understand and/or manage biological invasion could emerge from advances in community theory and the use of a functional framework. Targeting widely distributed invasive plants in different contexts and scaling up to ! eld situations will facilitate generalization.

With multiple species introductions and rapid global changes, there is a need for comprehensive invasion models that can predict community responses. Evidence suggests that abiotic constraint, propagule pressure, and biotic resistance of resident species each determine plant invasion success, yet their interactions are rarely tested. To understand these interactions, we conducted community assembly experiments simulating situations in which seeds of the invasive grass species Phragmites australis (Poaceae) land on bare soil along with seeds of resident wetland plant species. We used structural equation models to measure both direct abiotic constraint (here moist vs. flooded conditions) on invasion success and indirect constraint on the abundance and, therefore, biotic resistance of resident plant species. We also evaluated how propagule supply of P. australis interacts with the biotic resistance of resident species during invasion. We observed that flooding always directly reduced invasion success but had a synergistic or antagonistic effect on biotic resistance depending on the resident species involved. Biotic resistance of the most diverse resident species mixture remained strong even when abiotic conditions changed. Biotic resistance was also extremely effective under low propagule pressure of the invader. Moreover, the presence of a dense resident plant cover appeared to lower the threshold at which invasion success became stable even when propagule supply increased. Our study not only provides an analytical framework to quantify the effect of multiple interactions relevant to community assembly and species invasion, but it also proposes guidelines for innovative invasion management strategies based on a sound understanding of ecological processes.

The increasing area of abandoned rice fields could provide new opportunities for wetland restoration in Asia. However, it is unknown how quickly or completely abandoned rice fields will recover from agricultural disturbances. We assessed water quality and plant community succession in abandoned rice fields with different hydrology in a mountain valley to understand the effects of hydrological regime on recovery. Water level, soil redox potential, water quality, plant composition, and primary production were measured. The sites, coded as D6, N13, and N16, had been recovering for 6, 13, and 16 years by 2006. N13 and N16 have been recovering naturally whereas D6 has been drained with a nearby dike and was tilled in 2001. The typical hydroperiods of D6, N13, and N16 were no surface water, permanently flooded, and seasonally flooded, respectively. The major change in vegetation structure of both D6 and N13 was the replacement of herbaceous species by woody species. Drawdown accelerated this change because Salix koreensis grew better in damp conditions than in flooded conditions. Phragmites japonica reduced plot-level plant species richness. The removal efficiency of , , and from water varied seasonally, ranging between -78.8 to 44.3%, 0 to 97.5%, and -26.0 to 44.4%, respectively. In summary, abandoned rice fields quickly became suitable habitat for native wetland plant species and improved regional water quality. Variation among our sites indicates that it is likely possible to manage abandoned rice fields, mostly through controlling hydrology, to achieve site-specific restoration goals.