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Understanding the relationships among the environment, species traits and ecosystem properties is important for developing management measures that optimize the delivery of ecosystem services (ESs). Here, we identify the most important relationships responsible for the delivery of two key ESs provided by tidal marshes: (1) nature-based shoreline protection through wave attenuation and (2) mitigation of climate change through soil carbon storage. In two tidal zones below and above the mean high water (MHW, Elbe Estuary, Germany) level, we measured environmental parameters, such as soil salinity and inundation, as well as plant traits representing adaptations to hydrodynamic stress and strongly influencing decomposition rates. Multiple linear regression results showed that wave attenuation rates were positively related to aboveground community biomass and stem bending resistance, and soil organic carbon was positively related to stem specific density (below the MHW level). In the tidal zone above the MHW level, soil carbon density was governed by inundation duration and decomposition rates. Our study highlights that (1) ES delivery is not equally spread across tidal marshes and (2) ecosystem management should stimulate the development and persistence of habitat diversity (here, low and high marsh zones) to maximize ES delivery potential. Securing the delivery of the two studied ESs under climate change will depend on providing suitable (landward) space to sustain the functioning of the two marsh zones. In the studied marshes, these services are highly dependent on a few species (i.e., wave attenuation on Schoenoplectus tabernaemontani and Bolboschoenus maritimus and carbon storage on Phragmites australis), and as such, current and future ESs strongly depend on specific species' responses to changing environmental conditions. [ABSTRACT FROM AUTHOR]

Global change drivers such as eutrophication and plant invasions will create novel environments for many plant species. Through adaptive trait plasticity plants may maintain their performance under these novel conditions and may outcompete those showing low‐adaptive trait plasticity. In a greenhouse study, we determined if plasticity in traits is adaptive or maladaptive in endangered, nonendangered, and invasive plant species in response to variation of nitrogen (N) and phosphorus (P) availability (N:P ratios 1.7, 15, and 135) and whether plastic trait responses are adaptive and/or costly for fitness (i.e., biomass). Species choice comprised 17 species from three functional groups (legumes, nonlegume forbs, and grasses), either classified as endangered, nonendangered, or invasive. After 2 months, plants were harvested and nine traits related to carbon assimilation and nutrient uptake were measured (leaf area, SLA, LDMC, SPAD, RMR, root length, SRL, root surface area, and PME activity). We found more traits responding plastically to variation in P than in N. Plasticity only created costs when P was varied. Plasticity in traits was mostly adaptively neutral toward fitness, with plasticity in three traits being similarly adaptive across all species groups: SPAD (as a measure of chlorophyll content, adaptive to N and P limitation), leaf area, and root surface area (adaptive to P limitation). We found little differences in trait plasticity between endangered, nonendangered, and invasive species. Synthesis. Along a gradient from N limitation, balanced N:P supply, and P limitation, we found that the type of fluctuating nutrient (i.e., if N or P is varied) is decisive for the adaptive value of a trait. Variation in P availability (from balanced supply to P limitation) created both a stronger reduction in fitness as well as created plasticity costs in more traits than variation in N availability (from balanced supply to N limitation). However, the patterns observed in our study may change if nutrient availability is altered, either by nutrient inputs or by a shift in nutrient availabilities, for example, by decreasing N input as foreseen by European Legislation, but without simultaneously decreasing P input. [ABSTRACT FROM AUTHOR]

Background and Aims The acquisitive–conservative axis of plant ecological strategies results in a pattern of leaf trait covariation that captures the balance between leaf construction costs and plant growth potential. Studies evaluating trait covariation within species are scarcer, and have mostly dealt with variation in response to environmental gradients. Little work has been published on intraspecific patterns of leaf trait covariation in the absence of strong environmental variation. Methods We analysed covariation of four leaf functional traits [specific leaf area (SLA) leaf dry matter content (LDMC), force to tear (Ft) and leaf nitrogen content (Nm)] in six Poaceae and four Fabaceae species common in the dry Chaco forest of Central Argentina, growing in the field and in a common garden. We compared intraspecific covariation patterns (slopes, correlation and effect size) of leaf functional traits with global interspecific covariation patterns. Additionally, we checked for possible climatic and edaphic factors that could affect the intraspecific covariation pattern. Key Results We found negative correlations for the LDMC–SLA, Ft–SLA, LDMC–Nm and Ft–Nm trait pairs. This intraspecific covariation pattern found both in the field and in the common garden and not explained by climatic or edaphic variation in the field follows the expected acquisitive–conservative axis. At the same time, we found quantitative differences in slopes among different species, and between these intraspecific patterns and the interspecific ones. Many of these differences seem to be idiosyncratic, but some appear consistent among species (e.g. all the intraspecific LDMC–SLA and LDMC–Nm slopes tend to be shallower than the global pattern). Conclusions Our study indicates that the acquisitive–conservative leaf functional trait covariation pattern occurs at the intraspecific level even in the absence of relevant environmental variation in the field. This suggests a high degree of variation–covariation in leaf functional traits not driven by environmental variables. [ABSTRACT FROM AUTHOR]

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. Plain Language Summary: Plants play a critical role in the global carbon cycle, and diversity has been shown to influence vegetation productivity. However, when the land surface is simulated in a global model all wild plant life is reduced to a small number of plant functional types. Here we estimate how incorporating diversity influences ecosystem carbon uptake in 15 globe spanning landscapes. We find that diversity has a strong influence on modeled productivity, particularly in the arctic and tropics. Further, we find that whether plants shed their leaves annually has a strong influence on where traits fall within the global distribution and thus how traits and productivity interact. Key Points: We implemented distributions of leaf economic spectrum traits in a land surface model in 15 diverse landscapesTrait variation has a substantial influence on gross primary production (GPP)Phenology plays a key role in guiding where traits fall within the global trait distribution and hence trait‐GPP relationships [ABSTRACT FROM AUTHOR]

Aims: Silicon (Si) has been shown to beneficially affect plant performance under stressful environmental conditions, such as water or nutrient deficiency. Here we tested the effects of two important plant nutrients, nitrogen (N) and phosphorus (P), on Si content in different plant organs in the grass species Holcus lanatus. Methods: We studied trait responses to N limitation, balanced nutrient availability and P limitation. Single plant individuals were grown in sand-filled pots in a greenhouse for 2 months. Nitrogen, phosphorus, carbon and silicon contents were determined in leaves, stems and roots, as were leaf and roots traits, biomass production and root enzyme activity. Results: Si content was lowest under balanced nutrient supply in all plant organs. Under P limitation Si content was highest in leaves and stems, in roots it was highest under N limitation. Si:C ratios were lowest under balanced conditions, and highest under nutrient limitation. Root phosphatase activity was highest under P limitation and chlorophyll content was lowest under N limitation. Conclusions: Our model species assimilated less 'high cost C' and took up more 'low cost Si' under nutrient limitation, especially under P deficiency. Si potentially plays an important role in different environments, such as nutrient or light limitation, which in turn may be related to different plant strategies, for example higher stem rigidity in high Si plants versus higher stem flexibility in low Si plants. More research is needed to further elucidate the role of silicon in different concepts of trait-environment relationships. [ABSTRACT FROM AUTHOR]

Aims: Tidal marsh vegetation along estuaries is exposed to strong environmental gradients that determine which species — enabled through specific traits — can establish and persist. With these ecosystems under anthropogenic pressure, in-depth knowledge on the conservation of remaining tidal wetlands and restoration potentials is needed. In this study we elaborate the habitat conditions in the natural vegetation of the Elbe estuary and analyze: (a) which abiotic factors drive species composition; and (b) which species traits are key to the plants’ strategies in this specific ecotone. Location: Three sites in the Elbe estuary (river kilometer 671–703). Methods: We collected data on soil nutrients, inundation period and wave height and sampled traits of the 17 most abundant plant species, which we analyzed by RLQ (three-table analysis, including environment variables [R], species abundance [L] and a species traits table [Q]). Results: We detected a strong ˈwave–disturbance–inundation gradientˈ, which separated sparsely vegetated low-lying plots receiving high wave impact and exposed to long inundation periods, from high-lying plots showing dense vegetation and aerated soils. Close to the shore, plants showed low organ density and high investment into rhizomes, with a correlation of 0.72 between mass fraction of rhizome and phosphorus content of rhizome tissue. On higher elevations, plants strongly expressed traits relating to competition, like high allocation to stem biomass. Further, we found species with high leaf chlorophyll content showing low specific leaf area values and a negative correlation with the nutrient gradient. Conclusion: The results of our study are particularly relevant for restoration measures in order to re-establish healthy marsh vegetation. However, changes in the environmental conditions, for instance stronger wave energies by a higher shipping frequency in the river channel and sea level rise may trigger changes in species composition through plant trait adaptations, for example by demanding a stem flexibility beyond what would be structurally feasible. [ABSTRACT FROM AUTHOR]

Recent empirical and theoretical approaches have called for an understanding of the processes underpinning ecosystem service provision. Environmental gradients have shown effects on key plant functional traits that subsequently explain ecosystem properties of several systems. However, little is known concerning how associations between plant functional traits, including both below- and aboveground plant components, predict ecosystem properties and independently measured final ecosystem services. Here, we modeled (1) the responses of the leaf and plant economics spectrum, Plant size axis, and root growth to environmental gradients and (2) how associations between plant functional traits explain trade-offs and synergies between multiple ecosystem properties and final services. Forty-four plots were studied in a coastal marsh landscape of the German North Sea Coast. We used a partial least square structural equation model approach to test the hypothesized model. We found (1) a negative covariation between plant traits pertaining to a size axis and traits explaining both plant growth (roots and stems) and the leaf economics spectrum; (2) this trade-off responded significantly to the land use gradient and nutrient availability, which were both strongly driven by the groundwater gradient; (3) this trade-off explained an initial major trade-off between carbon stocks, at one extreme of the axis, and both the habitat value to conserve endangered plants and forage production for meat and dairy products at the other extreme. However, a secondary trade-off between nature conservation value and forage production, explained by a trade-off between leaf economics spectrum and plant growth in response to the land use intensity gradient, was also found. [ABSTRACT FROM AUTHOR]

The leaf economic spectrum is a widely studied axis of plant trait variability that defines a trade‐off between leaf longevity and productivity. While this has been investigated at the global scale, where it is robust, and at local scales, where deviations from it are common, it has received less attention at the intermediate scale of plant functional types (PFTs). We investigated whether global leaf economic relationships are also present within the scale of plant functional types (PFTs) commonly used by Earth System models, and the extent to which this global‐PFT hierarchy can be used to constrain trait estimates. We developed a hierarchical multivariate Bayesian model that assumes separate means and covariance structures within and across PFTs and fit this model to seven leaf traits from the TRY database related to leaf longevity, morphology, biochemistry, and photosynthetic metabolism. Although patterns of trait covariation were generally consistent with the leaf economic spectrum, we found three approximate tiers to this consistency. Relationships among morphological and biochemical traits (specific leaf area [SLA], N, P) were the most robust within and across PFTs, suggesting that covariation in these traits is driven by universal leaf construction trade‐offs and stoichiometry. Relationships among metabolic traits (dark respiration [Rd], maximum RuBisCo carboxylation rate [Vc,max], maximum electron transport rate [Jmax]) were slightly less consistent, reflecting in part their much sparser sampling (especially for high‐latitude PFTs), but also pointing to more flexible plasticity in plant metabolistm. Finally, relationships involving leaf lifespan were the least consistent, indicating that leaf economic relationships related to leaf lifespan are dominated by across‐PFT differences and that within‐PFT variation in leaf lifespan is more complex and idiosyncratic. Across all traits, this covariance was an important source of information, as evidenced by the improved imputation accuracy and reduced predictive uncertainty in multivariate models compared to univariate models. Ultimately, our study reaffirms the value of studying not just individual traits but the multivariate trait space and the utility of hierarchical modeling for studying the scale dependence of trait relationships. [ABSTRACT FROM AUTHOR]

Plant performance is driven by nutrient availability. So far, studies on plant nutrient relationships mostly focused on nitrogen (N) and phosphorus (P), whereas potassium (K) received less attention. We evaluated whether plant responses to variation in nutrient availability are similar or different for the nutrients N, P and K and whether the same plant traits are decisive for the competitive ability of species along gradients of N, P and K availabilities.We studied plant trait responses of three temperate perennial grass species (Alopecurus pratensis, Agrostis capillaris and Anthoxanthum odoratum, each dominant under N limitation, P limitation and K limitation, respectively). Each gradient consisted of eight treatments (N1–N8, P1–P8, K1–K8), with N:P:K supply rates being 1:0.8:6 (N1), 128:0.8:6 (N8), 12:0.075:6 (P1), 12:9.6:6 (P8), 12:0.8:0.56 (K1) and 12:0.8:72 (K8) (total supply per plant individual in mg). Plant individuals were kept either in single‐species pots (intraspecific competition) or in mixed‐species pots (interspecific competition). After 2 months, plant biomass, leaf and root traits and root enzyme activity were measured.Most below‐ground traits (e.g. total root length, root diameter) responded most strongly to competition as predictor variable and only secondly to the type of nutrient or their supply rates (unlike RGRTotal and SLA). Leaf chlorophyll content and root enzyme activity responded most strongly to supply rate of nutrients and the interaction of nutrient type and supply rate, respectively. In line with our prediction, A. pratensis was the superior competitor under N limitation and A. odoratum was the superior competitor under K limitation (assessed by relative dominance [RD] and relative competitive strength [RCS]). Both species showed high investment in total root length. Opposite to our expectation, A. capillaris was a bad competitor under P limitation, with low root length but higher root phosphatase activity.Our results indicate that below‐ground plant traits are decisive in nutrient‐related competition between plant species. Further, competitive strength is determined by a high total root length per soil volume both under N and K limitation. Under P limitation, the model species A. capillaris showed a weak competitive performance either because it was lacking colonization with mycorrhiza and/or the high investment in phosphatase activity posed a trade‐off with higher N investment in phosphatase production. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Questions: What is the functional trait variation of European temperate grasslands and how does this reflect global patterns of plant form and function? Do habitat specialists show trait differentiation across habitat types? Location: Europe. Methods: We compiled 18 regeneration and non‐regeneration traits for a continental species pool consisting of 645 species frequent in five grassland types. These grassland types are widely distributed in Europe but differentiated by altitude, soil bedrock and traditional long‐term management and disturbance regimes. We evaluated the multivariate trait space of this entire species pool and compared multi‐trait variation and mean trait values of habitat specialists grouped by grassland type. Results: The first dimension of the trait space accounted for 23% of variation and reflected a gradient between fast‐growing and slow‐growing plants. Plant height and SLA contributed to both the first and second ordination axes. Regeneration traits mainly contributed to the second and following dimensions to explain 56% of variation across the first five axes. Habitat specialists showed functional differences between grassland types mainly through non‐regeneration traits. Conclusions: The trait spectrum of plants dominating European temperate grasslands is primarily explained by growth strategies which are analogous to the trait variation observed at the global scale, and secondly by regeneration strategies. Functional differentiation of habitat specialists across grassland types is mainly related to environmental filtering linked with altitude and disturbance. This filtering pattern is mainly observed in non‐regeneration traits, while most regeneration traits demonstrate multiple strategies within the same habitat type. [ABSTRACT FROM AUTHOR]

Nature‐based mitigation is increasingly proposed as a strategy to cope with global change and related risks for coastal flooding and erosion. Tidal marshes are known to provide shoreline protection as their aboveground biomass attenuates waves and their belowground biomass contributes to reducing erosion rates. The aim of this study was to quantify how effectively wave attenuation rates and erosion reduction rates are sustained throughout seasons in pioneer tidal marshes in the Elbe estuary (Germany). Changes in hydrodynamics and sediment dynamics were measured during 17 months along three sea‐to‐land transects of 50 m length. Simultaneously, changes in biomass of the monospecific pioneer vegetation (Bolboschoenus maritimus) were measured monthly. This study shows that wave and flow attenuation rates positively correlate with seasonal variations in aboveground biomass, that is: in summer, aboveground biomass and associated wave and flow attenuation rates are highest; while aboveground biomass is washed away during the first storms in autumn or winter, resulting in low wave and flow attenuation rates. Contrastingly, maximum incoming wave heights and flow velocities occur during winter, indicating that wave and flow attenuation is most needed then. However, hibernating root biomass assures low erosion rates in winter, especially at sandy sites. Although wave attenuation by pioneer marshes is highly variable throughout seasons and pioneer marshes alone are not so effective, they might facilitate the survival of higher marshes. Therefore, it is important to conserve or restore a gradual sea‐to‐land gradient from tidal flats, over pioneer marsh to high marsh to provide nature‐based shoreline protection. [ABSTRACT FROM AUTHOR]

Correlations among plant traits often reflect important trade‐offs or allometric relationships in biological functions like carbon gain, support, water uptake, and reproduction that are associated with different plant organs. Whether trait correlations can be aggregated to "spectra" or "leading dimensions," whether these dimensions are consistent across plant organs, spatial scale, and growth forms are still open questions.To illustrate the current state of knowledge, we constructed a network of published trait correlations associated with the "leaf economics spectrum," "biomass allocation dimension," "seed dimension," and carbon and nitrogen concentrations. This literature‐based network was compared to a network based on a dataset of 23 traits from 2,530 individuals of 126 plant species from 381 plots in Northwest Europe.The observed network comprised more significant correlations than the literature‐based network. Network centrality measures showed that size traits such as the mass of leaf, stem, below‐ground, and reproductive tissues and plant height were the most central traits in the network, confirming the importance of allometric relationships in herbaceous plants. Stem mass and stem‐specific length were "hub" traits correlated with most traits. Environmental selection of hub traits may affect the whole phenotype. In contrast to the literature‐based network, SLA and leaf N were of minor importance. Based on cluster analysis and subsequent PCAs of the resulting trait clusters, we found a "size" module, a "seed" module, two modules representing C and N concentrations in plant organs, and a "partitioning" module representing organ mass fractions. A module representing the plant economics spectrum did not emerge.Synthesis. Although we found support for several trait dimensions, the observed trait network deviated significantly from current knowledge, suggesting that previous studies have overlooked trait coordination at the whole‐plant level. Furthermore, network analysis suggests that stem traits have a stronger regulatory role in herbaceous plants than leaf traits. Correlations among plant traits often reflect important relationships in biological functions like carbon gain, support, water uptake, and reproduction. We illustrate the correlations among 23 traits of 126 plant species using a graphical network approach. The analysis suggests that biomass allocation traits and stem traits have a stronger regulatory role in herbaceous plants than leaf traits. [ABSTRACT FROM AUTHOR]

Globally, many natural grasslands are becoming increasingly urbanised, with non-native plants invading as local and regional environmental attributes are altered. Using multiple linear regression models, we examined the functional trait composition of non-native plants in 69 native urban grasslands in Melbourne, Australia, against the spatial attributes of remnant patches and the surrounding road network at multiple spatial scales. We predicted that (1) urbanisation favours non-native plants with evolved characteristics conferring resistance to urban environments, (2) high road density in the immediate vicinity of remnants drives high non-native functional diversity, and (3) non-native plants that spread and become abundant do so through an investment in competitive traits. Non-native plants contributed to 31% of total grassland cover, with regionally widespread species dominant within sites. Non-native perennial grass cover, rather than annual grass cover, was positively associated with road density across the urban landscape, and community-weighted Specific Leaf Area was negatively associated with road density. At local scales, non-native plant functional diversity was positively associated with road density in the immediate vicinity of grasslands. Urbanisation favoured non-native plants invested in persistence over resource acquisition, potentially in response to the urban climate and declines in fire frequency. Re-introducing historic fire regimes may therefore have the potential to be a key strategy in reducing competition from non-native plants. High non-native functional diversity in areas of high local road density was the expected response to high propagule pressure. Urban planning that protects grasslands from road encroachment may therefore reduce invasion. [ABSTRACT FROM AUTHOR]

Abstract: Plant performance is correlated with element concentrations in plant tissue, which may be impacted by adverse chemical soil conditions. Antibiotics of veterinary origin can adversely affect plant performance. They are released to agricultural fields via grazing animals or manure, taken up by plants and may be stored, transformed or sequestered by plant metabolic processes. We studied the potential effects of three antibiotics (penicillin, sulfadiazine, and tetracycline) on plant element contents (macro‐ and microelements). Plant species included two herb species (Brassica napus and Capsella bursa‐pastoris) and two grass species (Triticum aestivum and Apera spica‐venti), representing two crop species and two noncrop species commonly found in field margins, respectively. Antibiotic concentrations were chosen as to reflect in vivo situations, that is, relatively low concentrations similar to those detected in soils. In a greenhouse experiment, plants were raised in soil spiked with antibiotics. After harvest, macro‐ and microelements in plant leaves, stems, and roots were determined (mg/g). Results indicate that antibiotics can affect element contents in plants. Penicillin exerted the greatest effect both on element contents and on scaling relationships of elements between plant organs. Roots responded strongest to antibiotics compared to stems and leaves. We conclude that antibiotics in the soil, even in low concentrations, lead to low‐element homeostasis, altering the scaling relationships between roots and other plant organs, which may affect metabolic processes and ultimately the performance of a plant. [ABSTRACT FROM AUTHOR]

Species conservation and forage production are both important, yet conflicting components of sustainable grassland management. We modeled forage production and conservation value as dependents in a chain of responses and effects, starting with abiotic environmental conditions that affect the spatial distribution of land uses and biotic ecosystem properties. We asked which relationships in this causal chain determine trade-offs between forage production and conservation value. Abiotic and biotic ecosystem properties were recorded on 46 plots in the coastal marshes of Northwest Germany. Plant and bird conservation values were calculated using Red Lists, and sales of forage-based agricultural products were assessed by interviewing farmers. We used a structural equation model to determine responses and effects. Groundwater depth and salinity represent the ultimate causes for the spatial variation in sales and conservation value. The water gradient translated into more proximate causes, such as land-use intensity affecting aboveground net primary productivity, forage quality, and species richness. Plant species conservation and forage production were segregated along the water gradient, and both bird conservation and forage production depended on grassland management, albeit at different fertilization levels. Our study points to segregation and integration as two spatial strategies to react to trade-offs between services. [ABSTRACT FROM PUBLISHER]

Ecosystems managed for production of biomass are often characterized by low biodiversity because management aims to optimize single ecosystem functions (i.e. yield) involving deliberate selection of species or cultivars. In consequence, considerable differences in observed plant species richness and productivity remain across systems, and the drivers of these differences have remained poorly resolved so far. In addition, it has remained unclear if species richness feeds back on ecosystem functions such as yield in real-world systems. Here, we establish N = 360 experimental plots across a broad range of managed ecosystems in several European countries, and use structural equation models to unravel potential drivers of plant species richness. We hypothesize that the relationships between productivity, total biomass and observed species richness are affected by management intensity, and that these effects differ between habitat types (dry grasslands, grasslands, and wetlands). We found that local management was an important driver of species richness across systems. Management caused system disturbance, resulting in reduced productivity yet enhanced total biomass. Plant species richness was directly and positively driven by management, with consistently negative effects of total biomass. Productivity effects on richness were positive, negative or neutral. Our study shows that management and total biomass drive plant species richness across real-world managed systems. [ABSTRACT FROM AUTHOR]

Questions As biodiversity losses increase due to global change and human-induced habitat destruction, the relationships between plant traits and ecosystem properties can provide a new level of understanding ecosystem complexity. Using a functional response-effect approach, we show that multiple components of the carbon cycle are determined by a few plant traits, which in turn are strongly affected by environmental conditions. Location Salt marshes, northwest Germany. Methods We explored responses of morphological, chemical and biomass-related plant traits to environmental drivers and examined their effects on carbon cycle properties, i.e. above-ground biomass, above-ground net primary productivity and decomposition. The combined analysis between environmental parameters, functional traits and ecosystem properties used structural equation modelling ( SEM). Results Important response and effect traits were leaf dry matter content ( LDMC) and below-ground dry mass ( BDM, responding to groundwater level and salinity) and leaf C:N ratio (responding to inundation frequency). Inundation and salinity led to increased allocation to below-ground biomass and salt stress adaptation in leaves, which translated into increased decomposition rates. Release from these abiotic controls resulted in standing biomass accumulation, which was controlled by LDMC and canopy height as key traits. Conclusions These findings demonstrate the interacting effects of non-consumable environmental factors and soil resources on morphological, chemical and biomass traits, which affected carbon cycle properties. Loss of species from the community has the potential to change the relationships between environment and vegetation-based ecosystem properties and therefore elicit effects on the multifunctionality of the entire and adjacent ecosystems. [ABSTRACT FROM AUTHOR]

Question: How do species traits respond to environmental conditions and what is their effect on ecosystem properties? Location: Salt marshes, Northwest Germany. Methods: On 113 plots along the German mainland coast and on one island, we measured environmental parameters (soil nutrient content, inundation frequency, groundwater level and salinity), collected traits from 242 individuals (specific leaf area [SLA], whole plant C:N ratio, and dry weights of plant organs) and sampled above-ground biomass as an ecosystem property. We constructed a path model combining environmental parameters, functional traits at community level and above-ground biomass, which was tested against a dependence model using path analysis; model fit was evaluated by structural equation modelling (SEM). Results: The final model showed good consistency with the data and highlights the major role of groundwater level, salinity and nutrient availability as the most important factors influencing biomass allocation in salt marshes. Above-ground living biomass was mostly determined by stem biomass, which was mediated through an allometric allocation of biomass to all other plant organs, including leaf mass. C:N ratio and SLA were the major drivers for dead biomass. Conclusion: We emphasize an indirect link between standing biomass and environmental conditions and recognize stem biomass, plant C:N ratio and SLA as keystone markers of species functioning in determining the relationship between environment and ecosystem properties. [ABSTRACT FROM AUTHOR]

Hedychium gardnerianum is a major invader of native Hawaiian forests and suspected of smothering native understory species and preventing native tree seedlings’ establishment. In this study, effects on species composition in six vegetation layers of a Hawaiian rainforest were examined (Tree Layer 1, Tree Layer 2, Fern-Shrub Layer, Herb Layer, Bryophyte–Herb Layer, and Bryophyte Layer). Three different area types were compared, which included (i) Natural area types with no influence of non-native species, (ii) Ginger area types with a Hedychium gardnerianum dominated herb layer, and (iii) Cleared area types, which were treated with herbicide to remove alien species in 1998. Species composition sampled in 2004 of the upper three vegetation layers (Tree Layer 1, Tree Layer 2, and Fern-Shrub Layer) differed little. The lower three vegetation layers (Herb Layer, Bryophyte–Herb Layer, and Bryophyte Layer) showed highly significant differences. Species composition in the Ginger area types showed notable abundances of non-native Psidium cattleianum, but low coverage of native species. In the area freed of Hedychium gardnerianum (Cleared area types), native species are regenerating, although it still reveals signs of disturbance. If this area is managed to prevent reinvasion, then it is likely to regain a natural forest structure. [ABSTRACT FROM AUTHOR]