Terms Of Functional Diversity Research Articles

Experimental warming altered plant functional traits and their coordination in a permafrost ecosystem.

Knowledge about changes in plant functional traits is valuable for the mechanistic understanding of warming effects on ecosystem functions. However, observations have tended to focus on aboveground plant traits, and there is little information about changes in belowground plant traits or the coordination of above- and belowground traits under climate warming, particularly in permafrost ecosystems. Based on a 7-yr field warming experiment, we measured 26 above- and belowground plant traits of four dominant species, and explored community functional composition and trait networks in response to experimental warming in a permafrost ecosystem on the Tibetan Plateau. Experimental warming shifted community-level functional traits toward more acquisitive values, with earlier green-up, greater plant height, larger leaves, higher photosynthetic resource-use efficiency, thinner roots, and greater specific root length and root nutrient concentrations. However, warming had a negligible effect in terms of functional diversity. In addition, warming shifted hub traits which have the highest centrality in the network from specific root area to leaf area. These results demonstrate that above- and belowground traits exhibit consistent adaptive strategies, with more acquisitive traits in warmer environments. Such changes could provide an adaptive advantage for plants in response to environmental change.

Evaluation of software for project management in the field of IT: Problems and prospects

Aim. The presented study aims to develop a model for evaluating software for project management in the field of IT and to outline opportunities for its implementation in an IT company. Tasks. The authors substantiate the problems and prospects of using software for project management in the field of IT; describe existing software for IT project management; develop an activity model reflecting the operating principles of the system for evaluating software for IT project management; substantiate opportunities for the practical application of the developed model; identify key criteria for selecting software for IT project management. Methods. This study uses the methods of theoretical analysis and synthesis, comparison, generalization, juxtaposition, abstraction, deduction and induction, content analysis, design and modeling, observation. Results. A model for evaluating software for project management in the field of IT is developed and substantiated. The possibilities, priority directions, and ways of its implementation in an IT company are described. The scientific and practical significance of the study consists in the argumentation for the conceptual framework of a model of a score-rating system for evaluating software for project management for the needs of an IT company. The model can be used when comparing software based on functional and score characteristics. Prospects for the development of the presented system include testing the model on various software for managing IT projects and adapting the model and its internal characteristics to the needs of the IT company, adjusting the proposed mechanism and conceptual framework of the evaluation system. Conclusions. The study establishes that the prospects for using the presented model are good in cases of a generalized cost-functional comparison of a wide range of software; detailed evaluation of the best software in terms of functional diversity (for example, a score comparison of the three best programs in terms of the total number of functional characteristics), which would reduce the final load on the user during evaluation; comparison of a small number of options when choosing from the most preferable software tools.

Environmental DNA reveals a mismatch between diversity facets of Amazonian fishes in response to contrasting geographical, environmental and anthropogenic effects.

Freshwater ecosystems are among the most endangered ecosystem in the world. Understanding how human activities affect these ecosystems requires disentangling and quantifying the contribution of the factors driving community assembly. While it has been largely studied in temperate freshwaters, tropical ecosystems remain challenging to study due to the high species richness and the lack of knowledge on species distribution. Here, the use of eDNA-based fish inventories combined to a community-level modelling approach allowed depicting of assembly rules and quantifying the relative contribution of geographic, environmental and anthropic factors to fish assembly. We then used the model predictions to map spatial biodiversity and assess the representativity of sites surveyed in French Guiana within the EU Water Framework Directive (WFD) and highlighted areas that should host unique freshwater fish assemblages. We demonstrated a mismatch between the taxonomic and functional diversity. Taxonomic assemblages between but also within basins were mainly the results of dispersal limitation resulting from basin isolation and natural river barriers. Contrastingly, functional assemblages were ruled by environmental and anthropic factors. The regional mapping of fish diversity indicated that the sites surveyed within the EU WFD had a better representativity of the regional functional diversity than taxonomic diversity. Importantly, we also showed that the assemblages expected to be the most altered by anthropic factors were the most poorly represented in terms of functional diversity in the surveyed sites. The predictions of unique functional and taxonomic assemblages could, therefore, guide the establishment of new survey sites to increase fish diversity representativity and improve this monitoring program.

Comparative genome analysis of Vagococcus fluvialis reveals abundance of mobile genetic elements in sponge-isolated strains

BackgroundVagococcus fluvialis is a species of lactic acid bacteria found both free-living in river and seawater and associated to hosts, such as marine sponges. This species has been greatly understudied, with no complete genome assembly available to date, which is essential for the characterisation of the mobilome.ResultsWe sequenced and assembled de novo the complete genome sequences of five V. fluvialis isolates recovered from marine sponges. Pangenome analysis of the V. fluvialis species (total of 17 genomes) showed a high intraspecific diversity, with 45.5% of orthologous genes found to be strain specific. Despite this diversity, analyses of gene functions clustered all V. fluvialis species together and separated them from other sequenced Vagococcus species. V. fluvialis strains from different habitats were highly similar in terms of functional diversity but the sponge-isolated strains were enriched in several functions related to the marine environment. Furthermore, sponge-isolated strains carried a significantly higher number of mobile genetic elements (MGEs) compared to previously sequenced V. fluvialis strains from other environments. Sponge-isolated strains carried up to 4 circular plasmids each, including a 48-kb conjugative plasmid. Three of the five strains carried an additional circular extrachromosomal sequence, assumed to be an excised prophage as it contained mainly viral genes and lacked plasmid replication genes. Insertion sequences (ISs) were up to five times more abundant in the genomes of sponge-isolated strains compared to the others, including several IS families found exclusively in these genomes.ConclusionsOur findings highlight the dynamics and plasticity of the V. fluvialis genome. The abundance of mobile genetic elements in the genomes of sponge-isolated V. fluvialis strains suggests that the mobilome might be key to understanding the genomic signatures of symbiosis in bacteria.

Stony coral tissue loss disease decimated Caribbean coral populations and reshaped reef functionality

Diseases are major drivers of the deterioration of coral reefs and are linked to major declines in coral abundance, reef functionality, and reef-related ecosystems services. An outbreak of a new disease is currently rampaging through the populations of the remaining reef-building corals across the Caribbean region. The outbreak was first reported in Florida in 2014 and reached the northern Mesoamerican Reef by summer 2018, where it spread across the ~450-km reef system in only a few months. Rapid spread was generalized across all sites and mortality rates ranged from 94% to <10% among the 21 afflicted coral species. Most species of the family Meandrinadae (maze corals) and subfamily Faviinae (brain corals) sustained losses >50%. This single event further modified the coral communities across the region by increasing the relative dominance of weedy corals and reducing reef functionality, both in terms of functional diversity and calcium carbonate production. This emergent disease is likely to become the most lethal disturbance ever recorded in the Caribbean, and it will likely result in the onset of a new functional regime where key reef-building and complex branching acroporids, an apparently unaffected genus that underwent severe population declines decades ago and retained low population levels, will once again become conspicuous structural features in reef systems with yet even lower levels of physical functionality.

Bird Functional Diversity in Agroecosystems and Secondary Forests of the Tropical Andes

Agricultural systems have increased in extension and intensity worldwide, altering vertebrate functional diversity, ecosystem functioning, and ecosystemic services. However, the effects of open monoculture crops on bird functional diversity remain little explored, particularly in highly biodiverse regions such as the tropical Andes. We aim to assess the functional diversity differences of bird guilds between monoculture crops (coffee, cocoa, and citrus) and secondary forests. We use four functional diversity indices (Rao Q, Functional Richness, Functional Evenness, and Functional Divergence) related to relevant morphological, life history, and behavioral traits. We find significant differences in functional diversity between agroecosystem and forest habitats. Particularly, bird functional diversity is quite homogeneous among crop types. Functional traits related to locomotion (body weight, wing-chord length, and tail length), nest type (closed), and foraging strata (canopy and understory) are dominant at the agroecosystems. The bird assemblages found at the agroecosystems are more homogeneous in terms of functional diversity than those found at the secondary forests, as a result of crop structure and management. We recommend promoting more diverse agroecosystems to enhance bird functional diversity and reduce their effects on biodiversity.

Plant trait filtering is stronger in the herb layer than in the tree layer in Greek mountain forests

We studied the differentiation among plant communities of deciduous broadleaved and mountain coniferous forests in terms of functional diversity and identity at a regional scale (northern and central Greece). We asked if patterns of functional differentiation among communities are consistent between the overstorey and understorey layers and if they can be influenced by deep past environmental conditions. Functional Richness (FRic) and Functional Dispersion (FDis), as well as their standardized effect sizes, were employed to assess the multivariate functional diversity of the community types. In contrast, single-trait Community Weighted Means (CWMs) were used as surrogates of functional identity. The aforementioned indices were calculated for three datasets, namely all the vascular plant taxa found in individual vegetation plots (total community), all phanerophyte (tree and shrub) taxa (overstorey) and all non-phanerophyte vascular plant taxa (understorey). We found that community types and especially four broad forest types (beech, ravine, pine and oak forests) are well differentiated in terms of functional composition (identity), as indicated by Non-Metric Multidimensional Scaling (NMDS). After conducting an NMDS for the three datasets, functional identity based on the total floristic composition was found to be the best discriminator of the studied communities. However, contrasting patterns were found for some specific traits or their categories between overstorey and understorey layers. The patterns of functional diversity of the community types (based on multivariate indices), revealed by calculating the standardized effect sizes of FRic and FDis based on the richness null model, did not differ substantially from random expectations for most of the studied community types when the dataset of all the vascular plant taxa was analyzed. However, the patterns revealed for the overstorey layer differed from those for the understorey layer. For the latter layer, the clustered structure was revealed in many community types based on the ses.FDis metric. Indications of deep past influence on the functional composition were found for certain community types (i.e. ravine forests) based on single-trait metrics, but no indication of such influence was found based on multivariate indices. Our findings highlight the complementarity and the additive explanatory value of the simultaneous use of single- and multi-trait approaches and their application to different layers in forests.

Functional diversity and redundancy of tropical forests shift with elevation and forest‐use intensity

Abstract Change and intensification of forest use alter tropical ecosystems, influencing biodiversity and, subsequently, ecosystem functioning. The implications of eroding biodiversity may go beyond decreases in species diversity, resulting in changes of functional diversity, that is, the diversity of ecological strategies present in the community, and functional redundancy, that is, how redundant these strategies are to biodiversity loss. However, how environmental conditions and anthropogenic influences shape functional diversity and redundancy in tropical forests remains poorly understood. Here, we examine how tropical forests respond to forest‐use intensity along an extensive elevational gradient in Mexico from the tropical lowlands to high‐elevational mountain forests (0–3,500 m), in terms of functional diversity and functional redundancy, and how these biodiversity facets are related to forest structure. In our study, elevation was crossed with three levels of forest‐use intensity: old‐growth, degraded and secondary forests. At eight elevational sites, five replicate plots were inventoried for each level of forest‐use intensity (total n = 120 plots). Functional diversity and redundancy were calculated using leaf and wood traits of 144 tree species for Hill numbers zero, one and two. Interactive effects between elevation and forest‐use intensity significantly affected biodiversity facets. However, interactive effects resulted from forest‐use intensity influencing biodiversity facets at only a few elevations, and not from a consistent, negative impact of forest‐use intensity. Forest structure, specifically stem density and the Gini coefficient, explained variation across biodiversity facets when these facets gave equal weight to common and rare species. Synthesis and applications. High functional diversity and functional redundancy from lowland to mid‐elevation tropical forests suggest that these ecosystems can be resilient to future disturbances. Our results indicate that the ability of high‐elevation forests may be particularly susceptible to climate change and increasing forest‐use intensity. For these high‐elevation forests, we recommend that forest managers implement enrichment plantings with native species that can tolerate future environmental conditions. Finally, our study shows that efforts to conserve structurally heterogeneous forests and actively managing forests to increase structural heterogeneity will enhance the resilience of tropical forests while conserving their biodiversity.

Observations on the floristic, life-form, leaf-size spectra and habitat diversity of vegetation in the Bhimber hills of Kashmir Himalayas

Vegetation analysis provides the prerequisites to understand the overall community structure and function of any ecosystem and is a fundamental requirement for the precise evaluation of biodiversity. Although many studies have assessed floristic attributes of specific areas, there are still unexplored regions, as is the case of the mountain region in the Kashmir Himalayas. Current research highlighted the recent findings of the scientific characterization of floristic and ecological aspects on the forest flora found in the Bhimber hills, Pakistan. Floristically, a total of 93 species belonging to 80 genera in 41 families were recorded. The species distribution patterns across the families were disproportionate with half of the species contributed by 8 families and 25 families were monotypic. Based on the floristic analysis, Asteraceae was the largest family with 12% of species followed by Poaceae with (11%) species. PAST software, a multivariate ecological community analysis was used to classify the species similarities and differences among the different habitat types. According to the habitat wise distribution, 21% of species were growing in the natural forest habitat, while 15% of species were dispersed in highly distributed habitats along roadsides and 8% on pedestrians. In terms of functional diversity, the herbaceous growth form was dominant (58%). The biological spectrum revealed therophytes as the dominant life form as it indicates the disturbed habitat vegetation. The phytogeographical analysis revealed that the maximum (69%) species were native, while the minimum (31%) species were exotic. Thus, the study of these functional and habitat diversity patterns can significantly improve our understanding of the ecological aspects of the flora in the geographical location. This information may additionally be useful in devising management plans to ensure sustainable utilization and better management of forest landscapes in this Himalayan region.

Effect of Invasive Alien Species on the Co-Occurrence Patterns of Bryophytes and Vascular Plant Species—The Case of a Mediterranean Disturbed Sandy Coast

Cross-taxon analyses can explain patterns of interaction between taxa and their application in conservation studies can drive management actions. In a coastal sand dune system characterized by a high human pressure, we explored the co-occurrence patterns between vascular plants and bryophytes, with a focus on how the occurrence of invasive alien species (IAS) can affect those taxa and their relationships. Species congruences were evaluated at the community level considering taxonomic and functional diversities. Predictive co-correspondence analysis (Co-CA) was applied to quantify the strength of vascular plant communities in predicting bryophytes species composition. The relationship between the composition of vascular plants and bryophytes was significant, even if weak. Altitude and percentage of bare soil cover are the environmental variables exerting greater influence on the two taxa. The presence of IAS affects communities in an opposite way: for vascular plants, species richness increases with the presence of invasive alien species; for bryophytes, IAS’s presence has a low but significant negative influence, both on species richness and in terms of functional diversity. Results give elements for future studies on the effect of IAS on the bryophytes colonizing coastal sand dunes.

Weed Seed Bank Diversity in Dryland Cereal Fields: Does it Differ Along the Field and Between Fields with Different Landscape Structure?

In this work, we aimed to test whether taxonomic diversity and functional diversity and the values of functional traits of the weed seed bank varied across the field, from margins to the core, and between fields embedded in distinct landscape structures. We sampled the seed bank of 47 conventionally managed cereal fields from two Mediterranean regions in Spain. In each field, three positions were selected: Margin, edge and core, and soil properties were measured for each position. Landscape structure was quantified for each field as the percentage of arable land in the surrounding 1 km radius circular sector. Seed bank diversity was characterized at the taxonomic (species richness, exponential Shannon index, and evenness) and functional levels (Rao’s quadratic entropy index and four corner analysis). For functional diversity, eight functional traits related to the whole plant life cycle were considered. Results showed a slight response of increasing taxonomic diversity from the core of the fields to the margins. Functional diversity was extremely low, indicating high similarity among species in terms of functional traits. Species in the seed bank were mostly therophytes, shorter than the crop plants, small seeded, flowering between the herbicide application of late winter and crop harvest, and showed seed dispersal by gravity or wind. This trait syndrome allows persistence in intensively managed arable lands. The similarity between fields in terms of functional diversity of the seed bank and in species traits may suggest that the intensity of management practices was similar across the fields. Moreover, it emphasizes that an increase in landscape heterogeneity, if based on other intensively managed cropping systems, may not be sufficient to augment functional diversity of weed communities. Therefore, in these areas, the seed bank could restore weed taxonomic diversity following changes in management practices, but functional diversity would still remain limited.

Drivers affecting mammal community structure and functional diversity under varied conservation efforts in a tropical rainforest in Cameroon

AbstractAs well as leading to a loss of biodiversity (i.e. species richness and abundance), human activities also affect ecosystem functioning. Documenting how the suite of ecological roles changes following disturbance provides a complementary source of information for conservation management. To this end, we measured mammal diversity in terms of community structure (i.e. abundance, composition and species richness) and functional diversity in three sites differing in conservation effort in a tropical rainforest in Cameroon. Results show that sites without primary or secondary conservation efforts had lower mammal abundances and an altered mammal composition but similar species richness compared to better‐protected areas. In terms of functional diversity, we found more variation of traits (i.e. FDis) in the site with primary conservation and higher abundances of functionally unique species (i.e. FOri) in sites with either primary or secondary conservation efforts. We found no overall difference in the abundance of specialist and generalist species between sites (i.e. FSpe). We identified several drivers affecting abundance, species richness and functional diversity of mammal communities, although there did not appear to be a common driver affecting all mammal diversity measures in a similar way. Our results suggest that, in addition to preserving mammal abundance and community composition, conservation efforts (both primary and secondary) are able to contribute to maintaining higher levels of functional diversity compared to areas devoid of conservation. We demonstrate that functional diversity metrics can provide valuable additional information about the status of mammal communities that can be used to better inform conservation management.

Climate and tillage system drive weed communities’ functional diversity in a Mediterranean cereal-legume rotation

The first step to develop an environmentally sound weed management is to know how weed communities respond to environmental drivers. Among these, climate and management practices are probably the more determinant factors for annual plants community assembly. In this framework, a trait based approach may be useful to assess weed community responses and the processes behind them. Here, we focused on three non-inversion tillage practices which differently affect soil conditions and the vertical distribution of weed seeds. We also took into account the climate variability across years. We specifically asked whether the type of non-inversion tillage system and the annual variability in climatic conditions explain the differences in the functional structure of weed communities. To assess this question we conducted a nine yearlong field experiment in which three non-inversion tillage systems were compared: subsoil tillage, minimum tillage and no-tillage. We characterized the functional structure of weed communities by first obtaining data on three resource acquisition traits (specific leaf area, plant height and growth habit) and five regenerative traits (seed weight, longevity index, dispersal structures, seed cover and emergence time). Then, we computed the community weighted mean (CWM) and the mean pairwise distance (MPD) of each trait as well as a multi trait MPD index. Climate annual conditions were characterized based on autumn-winter precipitation, average temperature and number of frost days. We found that tillage systems and climatic factors mainly sorted weed species according to their emergence time and seed weight. Weed communities from no-tillage plots were characterized by having an earlier emergence and seeds without pericarp. Regarding climatic conditions, we found that warmer and rainier autumn-winter conditions were related to lower functional diversity of regenerative traits and higher diversity in terms of resource acquisition traits. Our results highlight that factors affecting seedling emergence as well as traits related to these processes are critical during weed community assemblage. Our results also showed that none of the compared tillage systems was clearly outstanding in terms of functional diversity, but that each system benefited certain functional design. Furthermore, the relative importance of these management practices to drive weed functional structure was clearly lower than the effects of climatic inter-annual fluctuations.

Analyzing functional diversity to determine the effects of fish cages in insular coastal wild fish assemblages

Fish cages attract a high variety of wild fish, and therefore are similar to fish aggregation devices. Aquaculture cages enhance local fisheries, with a more diverse and abundant fish assemblages compared to control stations, not influenced by fish cages. Previous studies have been mainly focused on taxonomic and ecological indices, such as species richness, individual abundances or Shannon-Weaver index. In the present study, we explore if functional diversity may be feasible to understand the consequences of changes in the composition of fish aggregates around cages. We studied fish aggregates from three cages on the coast of Tenerife (Canary Islands, Atlantic Ocean) over several years. All fishes were identified and counted using rapid visual counts (RVCs) in cage and control stations. An increase of species richness and individual abundance occurred in fish aggregates around the studied cages persisting over time. Functional diversity showed increase on cage stations, with higher values of functional evenness and functional divergence relative to control stations. A slight dissimilarity in the taxonomic composition was only observed in the eastern farm. In terms of functional diversity, the studied aquaculture cages exhibited a slight increase in wild fish aggregates over time. These results are similar to previous studies based on taxonomic and ecologic diversity in which a long lasting effect was observed on wild fish aggregates. Thus, aquaculture cages might be considered as a figure of conservation or fishery interest. Statement of relevanceOur results showed a functionally diverse fish community around offshore cages. Thus, aquaculture leases could work as a “reservoir”, promoting the development of diverse fish assemblages, as marine protected areas (MPAs) are designed for.The development of aquaculture offshore cages might include their positive effects on wild fish aggregates, with a “buffer” fish-ban zone to protect fish stocks from the fishermen.

Conservative species drive biomass productivity in tropical dry forests

Summary Forests account for a substantial part of the terrestrial biomass storage and productivity. To better understand forest productivity, we need to disentangle the processes underlying net biomass change. We tested how above‐ground net biomass change and its underlying biomass dynamics (biomass recruitment, growth and mortality) can be explained by four alternative and contested hypotheses; the soil fertility, biomass ratio, niche complementarity and vegetation quantity hypotheses. Above‐ground biomass dynamics were evaluated over a 5‐year period in 200 permanent sample plots in 8 tropical dry forests in Brazil, and related to soil fertility, community‐weighted mean (CWM) traits that are important for carbon storage and sequestration (wood density, specific leaf area, maximum stem diameter and deciduousness), species richness, functional diversity and initial stand biomass. Initial stand biomass was the best predictor of all three processes of biomass dynamics, providing strong support for the vegetation quantity hypothesis. In these dry forests, the dominance of conservative species, rather than of acquisitive species, is associated with high biomass growth and storage, probably because their low specific leaf area and high wood density allow them to keep on functioning during drought stress. Paradoxically, high soil fertility (Ca) led to low biomass productivity, probably because of nutrient imbalance. In contrast to what is shown for controlled experiments, we found no support for niche complementarity (in terms of functional diversity or species richness) for forest productivity. Biomass storage was favoured by low‐ rather than high trait diversity, as most of the biomass is concentrated in species with large stem diameter and high wood density. Synthesis. Biomass dynamics are mainly shaped by vegetation quantity, and then by vegetation quality, in line with the mass ratio hypothesis. Dry forests show different trait‐productivity relationships than wet forests, as stands with ‘slow’ trait values are ‘fast’ in terms of productivity. Diversity matters, but in a different way than expected; high trait diversity does not enhance productivity, but instead, does low trait diversity enhance carbon storage.

Functional Trait Changes, Productivity Shifts and Vegetation Stability in Mountain Grasslands during a Short-Term Warming.

Plant functional traits underlie vegetation responses to environmental changes such as global warming, and consequently influence ecosystem processes. While most of the existing studies focus on the effect of warming only on species diversity and productivity, we further investigated (i) how the structure of community plant functional traits in temperate grasslands respond to experimental warming, and (ii) whether species and functional diversity contribute to a greater stability of grasslands, in terms of vegetation composition and productivity. Intact vegetation turves were extracted from temperate subalpine grassland (highland) in the Eastern Pyrenees and transplanted into a warm continental, experimental site in Lleida, in Western Catalonia (lowland). The impacts of simulated warming on plant production and diversity, functional trait structure, and vegetation compositional stability were assessed. We observed an increase in biomass and a reduction in species and functional diversity under short-term warming. The functional structure of the grassland communities changed significantly, in terms of functional diversity and community-weighted means (CWM) for several traits. Acquisitive and fast-growing species with higher SLA, early flowering, erect growth habit, and rhizomatous strategy became dominant in the lowland. Productivity was significantly positively related to species, and to a lower extent, functional diversity, but productivity and stability after warming were more dependent on trait composition (CWM) than on diversity. The turves with more acquisitive species before warming changed less in composition after warming. Results suggest that (i) the short-term warming can lead to the dominance of acquisitive fast growing species over conservative species, thus reducing species richness, and (ii) the functional traits structure in grassland communities had a greater influence on the productivity and stability of the community under short-term warming, compared to diversity effects. In summary, short-term climate warming can greatly alter vegetation functional structure and its relation to productivity.

Functional diversity as a framework for novel ecosystem design: The example of extensive green roofs

Novel urban ecosystems have recently gained importance and a consensus grows that ecosystem services are linked to ecosystem properties that in turn can be predicted by functional diversity (FD) of plant communities. Ensuring quality of life in cities is essential and approaches to improve ecosystem services should be encouraged. Here we analyzed the initial plant composition of commercial extensive green roof systems in terms of FD and propose two methods to compose species lists that maximize FD. Clustering techniques grouped the systems in three green roof types that differ in species richness and composition, substrate depth and installation method. Differences in FD and species richness between the types were considerable and correlations between FD and species richness were strongly positive, suggesting that species-rich systems generally have higher FD and thus offer better ecosystem services. Green roof systems that comprise only succulents have significant lower FD values compared to systems containing more diverse vegetation. Within the green roof types there was room for improvement of FD. Based on a species trait dissimilarity matrix, species lists that maximize FD for every green roof type were created. FD analysis of novel ecosystems enables the design of both species-poor and species-rich green roof systems with improved overall ecosystem services value. The described approach is generic in nature and can be used for a broad range of novel ecosystems and urban green elements. We believe that designing functional diverse plant systems will support a more sustainable urban planning and improve the quality of urban life.

Toward quantitative understanding on microbial community structure and functioning: a modeling-centered approach using degradation of marine oil spills as example.

Molecular ecology approaches are rapidly advancing our insights into the microorganisms involved in the degradation of marine oil spills and their metabolic potentials. Yet, many questions remain open: how do oil-degrading microbial communities assemble in terms of functional diversity, species abundances and organization and what are the drivers? How do the functional properties of microorganisms scale to processes at the ecosystem level? How does mass flow among species, and which factors and species control and regulate fluxes, stability and other ecosystem functions? Can generic rules on oil-degradation be derived, and what drivers underlie these rules? How can we engineer oil-degrading microbial communities such that toxic polycyclic aromatic hydrocarbons are degraded faster? These types of questions apply to the field of microbial ecology in general. We outline how recent advances in single-species systems biology might be extended to help answer these questions. We argue that bottom-up mechanistic modeling allows deciphering the respective roles and interactions among microorganisms. In particular constraint-based, metagenome-derived community-scale flux balance analysis appears suited for this goal as it allows calculating degradation-related fluxes based on physiological constraints and growth strategies, without needing detailed kinetic information. We subsequently discuss what is required to make these approaches successful, and identify a need to better understand microbial physiology in order to advance microbial ecology. We advocate the development of databases containing microbial physiological data. Answering the posed questions is far from trivial. Oil-degrading communities are, however, an attractive setting to start testing systems biology-derived models and hypotheses as they are relatively simple in diversity and key activities, with several key players being isolated and a high availability of experimental data and approaches.

Halobacterial Community Analysis of Mierlei Saline Lake in Transylvania (Romania)

In this study a combination of both molecular and biochemical methods have been used to characterize the bacterial microbiota in water and sediment of a saline lake in Transylvania. The physicochemical characterization of the water samples from different lake depths indicated a stratification of the lake that affects the distribution of resident microorganisms, confirmed also by the significant differences in terms of functional diversity of the microbial communities in different water layers. The superficial bacterial community shows a good oxidative capability, degrading a wide range of organic substrates, yet the bottom layer community exhibits a major level of specialization. The membrane fatty acid analysis of the sediment bacterial community shows the prevalent presence of Gram negative bacteria, confirmed by the culturing techniques. Among the 24 collected isolates, 16S rRNA gene sequencing analysis permitted to identify 10 different species, belonging to Bacillus, Halomonas, Idiomarina, Marinobacter, Pseudoalteromonas, Salinivibrio, Staphylococcus genera and prevalently classified as halophiles.

Isolation and characterization of endophytic bacteria from endorhizosphere of sugarcane and ryegrass

The present study was conducted with a view to isolate and characterize endophytic bacterial diversity from endorhizosphere of sugarcane (Saccharum sp.) and rye grass (Lolium perenne). Eight bacterial isolates from sugarcane and seven from rye grass were obtained and identified as Azospirillum, Bacillus, E. coli and Pseudomonas. S1 and R1 (Azospirillum) sugarcane and ryegrass isolate exhibited maximum nitrogenase activity of 1221.0 and 1168.3 nM C 2H 4h -1 mg -1 protein respectively while the maximum IAA production was recorded in S5 (E. coli) and R7 (Bacillus) i.e. 19.3 and 20.0 mg ml -1 respectively. The maximum siderophore production was observed in S6 (E.coli) and R6 (Pseudomonas) i.e. 2.4 and 3.0 mg ml -1 respectively. Only S5 (E.coli) was observed to be solubilize phosphate (21 mg P). The endorhizosphere of sugarcane and rye grass exhibited endophytic bacterial diversity not only in terms of different types of isolates but also in terms of functional diversity.