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Ecological restoration is critical for recovering degraded ecosystems but is challenged by variable success and low predictability. Understanding which outcomes are more predictable and less variable following restoration can improve restoration effectiveness. Recent theory asserts that the predictability of outcomes would follow an order from most to least predictable from coarse to fine community properties (physical structure > taxonomic diversity > functional composition > taxonomic composition) and that predictability would increase with more severe environmental conditions constraining species establishment. We tested this "hierarchy of predictability" hypothesis by synthesizing outcomes along an aridity gradient with 11 grassland restoration projects across the United States. We used 1829 vegetation monitoring plots from 227 restoration treatments, spread across 52 sites. We fit generalized linear mixed‐effects models to predict six indicators of restoration outcomes as a function of restoration characteristics (i.e., seed mixes, disturbance, management actions, time since restoration) and used variance explained by models and model residuals as proxies for restoration predictability. We did not find consistent support for our hypotheses. Physical structure was among the most predictable outcomes when the response variable was relative abundance of grasses, but unpredictable for total canopy cover. Similarly, one dimension of taxonomic composition related to species identities was unpredictable, but another dimension of taxonomic composition indicating whether exotic or native species dominated the community was highly predictable. Taxonomic diversity (i.e., species richness) and functional composition (i.e., mean trait values) were intermittently predictable. Predictability also did not increase consistently with aridity. The dimension of taxonomic composition related to the identity of species in restored communities was more predictable (i.e., smaller residuals) in more arid sites, but functional composition was less predictable (i.e., larger residuals), and other outcomes showed no significant trend. Restoration outcomes were most predictable when they related to variation in dominant species, while those responding to rare species were harder to predict, indicating a potential role of scale in restoration predictability. Overall, our results highlight additional factors that might influence restoration predictability and add support to the importance of continuous monitoring and active management beyond one‐time seed addition for successful grassland restoration in the United States. [ABSTRACT FROM AUTHOR]

There has been a growing interest in understanding how biodiversity affects the functioning of ecosystems, while, it is still unclear how and to what extent different aspects of biodiversity are related to ecosystems function. We tested the relationship between aboveground biomass (AGB) and various aspects of functional diversity (functional richness (FRic), functional evenness (FEve) and functional divergence (FDiv)), functional β diversity and functional composition. Our study areas were located in four different bioclimatic regions including desert-steppe, steppe, semi-steppe, and Mediterranean rangelands extending along a productivity gradient created by the elevational-rainfall variations in the central Zagros Mountains of Iran. The results showed that FDiv positively predicted AGB in more productive (i.e., Mediterranean) and negatively in less productive rangelands of desert-steppe, steppe and semi-steppe. Functional β diversity predicted AGB only in more productive regions in semi-steppe and Mediterranean rangelands. Functional β diversity decomposed into turnover and nestedness, with turnover being more important in more productive and nestedness being more important in less productive ecosystems. The results also showed that the effects of FD and functional β diversity on AGB are generally directed by animal grazing through homogenizing community - wide trait composition in less productive ecosystems and inducing shifting mosaics across locations in more productive ecosystem. The results indicate that different components of FD were significantly related to AGB and the strength and direction of these effects vary with the different components studied and the bioclimatic regions under the study. In higher productive ecosystems, both functional diversity and functional β diversity are likely to contribute more to AGB through the complementary use of the resources. In less productive ecosystems, however , the functional identity of dominant species and traits would drive AGB. [ABSTRACT FROM AUTHOR]

The Amazon harbors one of the most diverse tree floras on earth, and most species depend on mutualists for pollination and seed dispersal. This makes them susceptible to reproductive decline in fragmented forest because many of these mutualists suffer area‐related extinction in fragments. It remains unknown, however, whether this highly biodiverse tree flora will reproduce and ultimately persist in fragmented forest. We conducted a 2‐yr study of seed fall in an experimentally fragmented, highly diverse Central Amazonian forest. We determined the effect of fragment size (1, 10, 100 ha and continuous forest control) on the density, species richness, functional diversity and functional composition of seeds separated into two data sets: dispersed tree seeds, and undispersed tree seeds. Our results show a 3× reduction in the density of undispersed, non‐pioneer tree seeds in fragments of all sizes, indicating reduced seed production of the non‐pioneer tree community. The density of dispersed tree seeds was reduced by 6× in fragments of all sizes, while species richness was reduced by 6× in 1‐ha fragments and by 3× in 10‐ and 100‐ha fragments compared to intact forest. This provides evidence of reduced community‐wide seed dispersal, which became more pronounced with declining fragment size. The functional diversity (FRic) of dispersed tree seeds was reduced 9.6× in small fragments, and significant shifts in the functional composition for 8 of the 10 reproductive and ecological traits studied were identified, suggesting compromised ecosystem functioning. These functional compositional shifts provide evidence for disrupted mutualistic processes in fragments, which include loss of pollination by bees, especially small eusocial (meliponid) bees, and loss of dispersal by primates and large birds, which reduced the frequency of large‐seeded tree species. Fragments also lost rare and mature‐forest species, and collectively these changes suggest that future tree communities in fragmented Amazonian landscapes will retain a taxonomically and functionally impoverished species pool with a biased functional composition unless efforts are undertaken to conserve dispersal by large frugivores and pollination by meliponid bees. [ABSTRACT FROM AUTHOR]

Given current urbanization trends, understanding the factors that affect local biodiversity is paramount for designing sound management practices. Existing evidence suggests that the assembly of urban communities is influenced by the environmental filtering of organisms based on their traits. Here, we investigate how environmental characteristics including isolation measurements affect the functional composition of avian assemblages in green spaces of Merida, Mexico, a Neotropical city. We sampled 22 sites, analyzed point-count data collected during fall migration, and characterized the habitat with regard to floristic and structural vegetation attributes, vegetation cover within green spaces, urban infrastructure, and isolation. We assessed the relationship between habitat descriptors and bird functional traits using RLQ and fourth-corner tests and compared trait–environment associations between resident and wintering species. Our results showed that functional composition of resident bird assemblages was linked to the environmental characteristics of the site, while the functional composition of wintering species was not. In particular, the degree of isolation revealed to be an important determinant of trait composition. Plant species richness, particularly native tree and shrub species, were critical for the functional composition of resident birds in green spaces. Our findings suggested shifts in body mass from less to more isolated green spaces. Specifically, we observed that large-bodied species predominated in isolated green spaces. This information is useful given the predicted increases in habitat isolation and transformation of green spaces due to urbanization. [ABSTRACT FROM AUTHOR]

Given current urbanization trends, understanding the factors that affect local biodiversity is paramount for designing sound management practices. Existing evidence suggests that the assembly of urban communities is influenced by the environmental filtering of organisms based on their traits. Here, we investigate how environmental characteristics including isolation measurements affect the functional composition of avian assemblages in green spaces of Merida, Mexico, a Neotropical city. We sampled 22 sites, analyzed point-count data collected during fall migration, and characterized the habitat with regard to floristic and structural vegetation attributes, vegetation cover within green spaces, urban infrastructure, and isolation. We assessed the relationship between habitat descriptors and bird functional traits using RLQ and fourth-corner tests and compared trait–environment associations between resident and wintering species. Our results showed that functional composition of resident bird assemblages was linked to the environmental characteristics of the site, while the functional composition of wintering species was not. In particular, the degree of isolation revealed to be an important determinant of trait composition. Plant species richness, particularly native tree and shrub species, were critical for the functional composition of resident birds in green spaces. Our findings suggested shifts in body mass from less to more isolated green spaces. Specifically, we observed that large-bodied species predominated in isolated green spaces. This information is useful given the predicted increases in habitat isolation and transformation of green spaces due to urbanization. [ABSTRACT FROM AUTHOR]

Highlights • Vegetation surveys of extensive green roofs in Germany 20 years since installation. • The observed vegetation was defined by generalist (CSR) and stress-tolerator traits. • Half of the originally sown species that disappeared had competitive traits. • Colonising species comprised more than half of the observed cover. • Nine of the top 10 observed species were from original lists. Abstract Like any constructed ecosystem, the vegetation of extensive green roofs (EGRs) will change over time. Although this may influence the desired function and performance, little work has examined the floristic dynamism of EGRs over the long-term. Variations in species composition may be associated with original species (persistent or lost), colonisers (gained), or the effects of spatial heterogeneity. This paper reports on floristic variation of two unmanaged German EGRs twenty years after installation. To evaluate floristic change, the analyses focused on functional composition and plant strategies sensu Grime's CSR theory, referring to the basic adaptive strategies of competition, stress-tolerance and ruderality, and their derivatives. With reference to original documentation, less than half the original species persisted. In spite of the losses, both roofs had entire cover, or nearly so, thanks to colonising species. The generalist strategy (CSR strategists) was the most important functional trait in the observed vegetation, followed by stress-tolerance and then by variations in stress-tolerant ruderality. The functional composition of colonising species was chiefly ruderals, followed by stress tolerators and generalists. The drivers behind these changes relate to the pressures of stress, disturbance and competition, as well as spatial heterogeneity and strategies for dispersal and regeneration, seedbank and propagule sources. This study suggests that long-term floristic diversity may be facilitated by ensuring a diversity of traits and species from the start, by providing spatial heterogeneity, and by considering the mechanisms that support persistence and those which determine colonisation. [ABSTRACT FROM AUTHOR]

Highlights • Logging of humid tropical forests affects seed dispersal, wood and carbon stocks. • Logging impacts decreased seed size and biomass but not species richness. • 30 years after logging, forest composition still differs from initial state. Abstract Tropical forests harbor the greatest terrestrial biodiversity and provide various ecosystem services. The increase of human activities on these forests, among which logging, makes the conservation of biodiversity and associated services strongly dependent on the sustainability of these activities. However the indicators commonly used to assess the impact of forest exploitation, namely species richness and biomass, provide a limited understanding of their sustainability. Here, we assessed the sustainability of common forest exploitation in the Guiana Shield studying the recovery of two ecosystem services i.e. carbon storage and wood stock, and an ecosystem function i.e. seed dispersal by animals. Specifically, we compared total and commercial biomass, as well as functional composition in seed size of animal-dispersed species in replicated forest plots before and 27 years after exploitation. Species richness is also studied to allow comparison. While species richness was not affected by forest exploitation, total and commercial biomass as well as seed size of animal-dispersed species decreased 27 years after exploitation, similarly to forests affected by hunting. These results show that ecosystem services and function likely did not recover even at the lowest intensity of forest exploitation studied, questioning the sustainability of the most common rotation-cycle duration applied in the tropics. [ABSTRACT FROM AUTHOR]

Protected areas are intended to promote biodiversity representation and persistence; yet, whether they are effective in degraded landscapes where much of the original vegetation structure remains intact has received relatively little attention. We test whether avian assemblages in communal rangelands in savannas differ from savannas supporting a full complement of native herbivores and predators. Birds were surveyed in 36 transect counts conducted over 18 days. We also compare the vegetation structure between the two land-use types to assess whether differences in bird assemblages could be attributed to changes in vegetation structure. Bird assemblages were richer, had greater abundances and different compositions inside protected areas than rangelands. The median body mass of birds was larger inside than outside protected areas, and rangelands supported fewer grassland specialists, but more closed-canopy specialists. However, no differences in feeding guild composition were found between protected areas and communal rangelands. Additionally, vegetation structure, but not richness, differed between protected areas and communal rangelands: communal rangelands had higher densities of woody vegetation and shorter grass height than the protected areas. Our findings suggest that the altered vegetation structure in communal grazing camps has led to changes in the species richness and composition of bird communities and has been selected by closed-canopy specialists at the cost of open grassy specialists. Hunting in communal rangelands is likely to have resulted in the loss of large birds and in reductions in bird abundance in the rangelands. Therefore, land-use management that does not lead to irreversible landscape transformation can nevertheless result in changes in the diversity, composition and functioning of native assemblages. Conservation implications: Savanna landscapes that are degraded, but not transformed, support fewer bird species, fewer open habitat specialists and smaller birds because of vegetation homogenisation. [ABSTRACT FROM AUTHOR]

• A positive relationship between carbon stock and tree species richness was found in a second-growth tropical forest. • The distribution of leaf phenological functional groups influenced cobenefits in second-growth tropical forests. • Evergreen and deciduous functional groups contributed to high species richness and high carbon stock, respectively. • Differences in wood density drive differences in functional composition between deciduous and evergreen species. • Changes in the functional composition will be mediated by the traits associated with each phenological strategy. Second-growth tropical forests offer important carbon and biodiversity cobenefits, as well as different leaf functional types of tree species. Leaf deciduousness is an important functional trait that can contribute to seasonal and spatial changes in carbon balance. We investigated the distribution pattern of carbon stock, species richness, and functional dominance among trees with differing leaf phenology (evergreen, semideciduous and deciduous) as well as the carbon and biodiversity cobenefits of tree communities in contrasting topographical conditions in a second-growth tropical Atlantic forest. We tested the hypotheses that topographic conditions shape differences in species richness and aboveground carbon stock between leaf phenology groups, as well as the carbon-biodiversity cobenefits within the tree communities. We studied fourteen 20 m × 40 m plots established in the forest with contrasting topographical conditions. We selected the mean functional traits related to carbon stock capacity in tropical forest: wood density and maximum tree height and calculated community-weighted mean metrics based on these traits. Aboveground biomass of trees for each stem sampled was calculated from a combination of variables using the general allometric equation. We constructed linear mixed-effect models (LMMs, with random and fixed effects) to test the cobenefits between aboveground carbon stock and leaf phenology group (evergreen, semideciduous and deciduous species) on species richness at community level. Our results showed that evergreen species had a higher richness, while the deciduous species had a greater contribution to aboveground carbon stock. Thus, the leaf phenology groups can affect the relationships between species richness and aboveground carbon stock. The deciduous species are key to maintaining higher carbon stock with smaller numbers of species; meanwhile evergreen species are important to maintain a higher species richness. Leaf phenology groups could be responsible for important cobenefits (i.e. positive aboveground carbon stock and species richness relationship) in Atlantic forests. Therefore, this study showed a relevant result on the relative contribution of leaf phenology groups in the carbon and biodiversity cobenefits along topographic gradients. In addition, our results allow for the selection of key tree species to improve management, conservation and restoration practices in the Atlantic forest in order to protect threatened biodiversity as a cobenefit of maintaining forests and the carbon they store. [ABSTRACT FROM AUTHOR]

[Display omitted] • In mature growth tropical rainforests there is spatial variation in liana community dynamics, mostly driven by mortality. • Liana recruitment was positively related to fast water use trait values, better light condition, and phosphorus-rich soil conditions. • Liana growth rate was increased with higher elevation and better soil water availability. • Liana mortality was driven by biotic characteristics, and increased with more carbon acquisitive trait values. • Functional properties are more important than the environment in shaping liana community dynamics. Lianas have a major influence on community and ecosystem processes in tropical forests, but their dynamics and underlying drivers have rarely been assessed. This study evaluates which demographic processes underlie liana community change and how these demographic processes are driven by abiotic factors (light gaps, soil nutrients, soil water availability, and topography), and biotic factors such as competition by life forms (liana and tree basal area) and the functional properties of the liana community. In a tropical rainforest in Southwest China > 20,000 liana individuals were monitored in 20 1-ha plots and for each plot, average trait values of the liana community were determined for eighteen functional traits that are important for plant performance. Across the 20 plots, changes in liana density were more strongly driven by mortality than by recruitment. Liana recruitment and mortality were driven by biotic factors, especially the functional properties. Liana mortality was higher for acquisitive communities, possibly because of strong competition amongst fast-growing liana species and the short lifespan of pioneers. Liana growth was driven by abiotic factors and increased with elevation and soil water availability. Hence, liana community dynamics are shaped by mortality, and functional properties are more important than the environment. Simultaneously testing the roles of multiple environmental factors and inherent plant characteristics yields better insights into the mechanisms underlying community dynamics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil nutrients promoted soil organic carbon (SOC) storage better than topographic factors. • Tall big-sized trees with acquisitive functional strategy related negatively to SOC storage. • Remaining-sized trees weakly predict SOC storage due to big-sized trees effect. • The niche complementarity effect weakly explains SOC storage, irrespective of tree sizes. • Mass ratio effects on SOC storage depend on the trait identity of tree sizes. Soil organic carbon (SOC) storage plays a crucial role in mitigating global climate change while maintaining forests and sustaining environmental conditions. Recent studies have shown that plant species diversity increases SOC storage in experimental grasslands and natural forests. Here, we aim to show how an integrating tree-size and trait-based ecological approach leads to mechanistic insights into SOC storage that may be overlooked in previous studies. We hypothesized that tree functional diversity effects on SOC storage would change with tree-sized-based species' functional strategies driven by soil properties in natural temperate deciduous forests. We used the forest inventory data, site-specific measured traits and soil properties from 99 temperate deciduous forest plots in northwestern Iran. We investigated the joint effects of topographic factors, soil chemical properties, and the functional attributes (multi-trait functional diversity indices and community-weighted trait mean indices) of big-sized trees (BsT; individual tree diameter ≥ 50 cm) and remaining-sized trees (RsT) on topsoil (0–30 cm) SOC storage. The multiple linear regression models showed that SOC storage increased with increasing soil available phosphorus (r = 0.36), soil exchangeable potassium (r = 0.27 to 0.31) and soil total nitrogen (r = 0.27). In contrast, SOC storage declined with increasing the community-weighted mean of specific leaf area (r = −0.38 to −0.40). The structural equation model showed that SOC storage was directly driven by the positive effect of soil nutrients (i.e. a latent variable of soil total nitrogen and available phosphorus; r = 0.42) and the negative effect of the community-weighted mean of specific leaf area (r = −0.31). The topographic factors as well as the other several functional attributes of BsT and RsT showed non-significant direct and indirect effects on SOC storage in both types of statistical modelling. Our study suggests that the mass ratio and soil fertility rather than the niche complementarity effects along with the big-sized trees effect regulates SOC storage through the acquisitive trait identity of BsT species as compared to RsT species in temperate deciduous forests. We argue that maintaining high levels of species diversity with the most efficient trait identity across tree sizes is important for biodiversity conservation and multiple forest functions such as SOC storage which should be a priority for plantation management plans or silvicultural practices in natural forests. [ABSTRACT FROM AUTHOR]

Implementation of stationary systems of continuous monitoring technical state of power transformers is considered to be an important and relevant task. The paper provides a summery on the systems implemented at transformers of OJSC Magnitogorsk Iron and Steel Works. It characterizes the transformer of the power generating set of the thermal power plant equipped with the system for monitoring technical state. It lists diagnostic methods and offers an integrated system structure. The monitoring system is based on TDM package developed by OAO Dimrus. As a device for oil condition control, the Hydran M2 analyzer identifying gases dissolved in oil was used. Functions of separate modules, their version and arrangements are under consideration. The system interface is characterized, too. The main screen of controlled parameter of the transformer is provided in Inva-format. There is a challenge to develop methods for fault localization and identification based on the total of diagnostic features. The paper highlights a practical need for investigation of discharge activity with portable devices for control of partial discharges. [ABSTRACT FROM AUTHOR]

Programming languages greatly influence the way how programs are created and evolved. This means that the use of appropriate language for solved problem can greatly increase developer productivity. Composition of languages can provide great help in construction of a new language from existing components and for integration of several languages that may be needed to effectively solve a complex problem. In this paper we analyze the composition problem on the two levels: composition of languages and composition of concepts in a language. Possibilities of transition from language composition to concepts composition are also presented. Based on that, we propose a framework of languages construction based on concept composition that aims to support reusability of language elements and tools. It uses common host syntax for developed languages. Their semantics is defined in a general-purpose language. Proposed approach is demonstrated on example languages developed using prototype implementation. [ABSTRACT FROM AUTHOR]

• We monitored a small forest fragment in the Atlantic Forest hotspot for 30 years. • Long-term trends on trees biomass, density and functional composition were evaluated. • We found structural and compositional changes towards advanced sucessional stages. • Long-term trends were marked by forest biomass increase due to full protection. • Small fragments play important role in carbon uptake and biodiversity protection. Forest dynamics are driven by a myriad of factors and link directly to ecosystem services. The dynamics of the highly degraded Brazilian Atlantic Forest (AF) hotspot is mostly driven by its anthropogenic context. Currently, most of the AF region is composed of small disturbed secondary forest fragments that have received partial or full environmental protection with recent environmental norms. Such protection prevents further disturbances and consequently shifts the course of forest dynamics and ecosystem services in AF. Here, we assess long-term forest dynamics trends of a small secondary AF fragment to test the hypothesis that disturbed AF fragments are reaching advanced successional stages. We used a unique dataset of 126 permanent subplots (totaling 5.04 ha) monitored for 30 years (8 inventories between 1987 and 2017) of a disturbed secondary AF fragment (6.35 ha) that has been fully protected since 1986. In each inventory, we measured all living trees with a diameter at breast height (DBH) ≥ 5 cm and counted survivors, recruits and dead individuals between intervals. We monitored the temporal trends of (i) structural variables (biomass, tree density and species richness), (ii) functional composition (wood density and maximum potential size), (iii) and species dominance. Our results indicate that, now under full protection, the fragment is shifting towards a late successional stage: we observed increasing biomass, decreasing tree density (self-thinning) and increasing abundance of late-successional species with conservative strategies. Species richness and dominant species composition were stable throughout the monitoring period, suggesting an absence of substantial changes in community assembly. These results underscore the role played by small secondary AF fragments in ecosystem service provision (e.g., carbon uptake and shelter for biodiversity) and point to their forest dynamics trends. [ABSTRACT FROM AUTHOR]