Clonal plants—What is their role in succession?

Fifteen successional seres from man-made habitats in central Europe were compared and the occurrence of clonal species assessed on the basis of cover data. The effects of soil moisture and nitrogen (expressed using Ellenberg indicator values) on the performance of clonal plants were also considered. Clonal species formed the dominant component of vegetation cover in the majority of the seres studied. In moist sites, their dominance was more pronounced and the peak in their relative cover occurred earlier in succession. The relative importance of species with guerilla type growth tended to increase with time in most seres and after 10 years these were mostly more important than those exhibiting phalanx type growth. The prevalence of guerilla species after 10 years was more obvious in moist seres. Clonal species were able to become dominant regardless of soil conditions, whereas the dominance of non-clonal species tended to be restricted to very wet and nutrient-poor sites. Clonal plant species appeared to maintain their dominance for a longer period than non-clonal plants.     

Spontaneous vegetation succession in human‐disturbed habitats: A pattern across seres

Abstract. Vegetation samples from 15 successional seres in various disturbed habitats in the western part of the Czech Republic were analysed to detect possible trends. For particular seres, data on species cover were available from the onset to 10–76 yr of succession. All seres started on bare ground. Species which attained at least 1% cover in any sere in any year were used as input data for Canonical Correspondence Analysis, assessing the effect of time as the environmental variable, for Detrended Correspondence Analysis and TWINSPAN classification. Two distinct groups ofseres were distinguished: ‘ruderal’, occurring in agricultural, industrial or urban landscapes altered by men, usually on fertile sites; and ‘non‐ruderul’, occurring in less altered, mostly forested landscapes, usually on acid, nutrient‐poor and wetter soils. The former type of succession starts with ruderal annuals, being followed by ruderal perennials. In the latter case non‐ruderal clonal perennials prevail from the onset of succession. The landscape frame is emphasized, beside site environmental conditions, as influencing the type of succession. The character of species attaining dominance in succession, participation of dominant woody plants and the character of late successional stages, i.e. features important from the point of view of potential restoration of human‐disturbed habitats, are discussed.     

Spontaneous Establishment of Woody Plants in Central European Derelict Sites and their Potential for Reclamation

The performance of woody plants was analyzed in 15 successional seres starting at bare ground in central European manmade habitats. The total cover of woody species after 10 years of succession was significantly related neither to initial soil moisture nor to nitrogen (expressed using Ellenberg indicator values). But the comparison of seres indicates that establishment of woody plants was easier under moderate environmental conditions and retarded in extreme habitats (dry, nutrient-poor, or acid). The arrival of the first woody plants was delayed in dry sites. No significant differences were found between primary and secondary seres, either with respect to the total cover of woody plants reached after 10 years of succession or considering the time of their arrival. In total, 24 woody species (10 shrubs and 14 trees) appeared in the series investigated. Their successional performance (in terms of the number of seres in which the species occurred and maximum cover reached in any sere) was not related to species traits (life strategy, type of mycorrhizae, mode of dispersal, diaspore weight), except for the regeneration strategy, species with seasonal regeneration by seeds were capable of creating higher cover. Betula pendula (European birch) was the most successful species in spontaneous succession, especially on moist sites. Practical suggestions for the management of particular habitats (sites disturbed by mining, sites reclaimed after acid rain deforestation, urban sites, abandoned fields) are provided regarding the establishment of woody plants.     

Environmental gradients and succession patterns of carabid beetles (Coleoptera: Carabidae) in an Alpine glacier retreat zone

Accelerated by global warming, retreating glaciers leave behind spatially ordered moraines with underlying primary succession and disturbance. Current knowledge of primary succession comes mainly from studies of vegetation dynamics. Information about above-ground macroinvertebrates is still scarce. We used carabid beetles (Coleoptera; Carabidae) as indicator taxon to assess the effects of (1) terrain age (species turnover along the proglacial chronosequence) and (2) small-scale habitat architecture (vegetation cover, surface texture) on the carabid assembly. For this purpose, 33 sampling sites with pitfall traps were installed throughout the glacier foreland Morteratsch (Engadine, Switzerland), adjacent sparse forests serving as reference sites. With a total of 33 carabid species on the foreland and another 2 on the reference sites, the study area yielded a very high carabid species diversity compared to other glacier forelands. In general, the age of deglaciation proved to be a highly significant predictor for the carabid distribution, especially for particularly discriminant species. Observed species richness and activity densities showed bimodal patterns with a steep increase within the first ca. 40?years, a decline between around 40–90?years, and a further increase towards the terminal moraine. There was no evidence of dispersal-stochasticity: distinct clusters of sites with similar species composition were found. Microhabitat suitability proved to be a secondary effect, embedded in a temporal framework of primary succession. Surface cover with litter, herbs and dwarf-shrubs turned out to be the crucial habitat factors. Habitat loss as a result of climate warming will primarily affect cold-stenotopic carabids, but may potentially be absorbed by active selection for cooler microhabitats.     

How do species dominating in succession differ from others?

Abstract. Data on succession were collected from 15 seres starting on bare ground in man-made habitats (i.e. sites disturbed by various mining activities, bulldozed sites, ruderal urban sites, the exposed bottom of a destroyed water reservoir, and abandoned fields), all in the western part of the Czech Republic, Central Europe. The period for which the data on succession were available ranged from 12 to 60 yr. 56 species reaching dominance in some period of succession were selected (the criterion being: at least 25 % cover in at least one year in any sere); they were compared for biological and ecological traits with other species participating in the seres (167 species with at least 1 % cover in at least one year in any sere), and with the Central European flora as a whole. Significant differences between the species dominating in succession and others were found for the following traits: life form, life strategy, pollination mode, and ability of lateral spread. Dominant species differed from the regional flora in distribution of life strategies, pollination mode and immigration status. The results suggest that an ‘ideal successional dominant’ is a tall, wind-pollinated plant, often a geophyte capable of intensive lateral spread, requiring high nutrient supply and sufficient site moisture. The set of traits contributing to achieving dominance by a species in human-made habitats includes both features occurring independently of phylogenies (life strategy, pollination mode, plant height, moisture demands) and those which dominant species probably share due to their common ancestors (nutrient demands, capability of extensive lateral spread).     

Prediction of Vegetation Succession in Human-Disturbed Habitats Using an Expert System

Detailed information, both quantitative and observational, on the course of vegetation succession in various human-disturbed habitats in Central Europe was used to construct an expert system named SUCCESS. Using the system, it is possible to predict tentatively the sequence of seral stages and dominant species exchange in successional seres initiated on bare ground and lasting up to 50 years. Simple information on geographical position, type of substratum, relief, moisture, nutrient content, character of surrounding vegetation, and size of the disturbed area is taken into consideration to predict site-specific succession in the particular habitats. The expert system is supposed to help landscape managers, nature conservationists, and environmental impact assessment experts in decision-making procedures to take into account the development of vegetation in man-made sites. Moreover, it also summarizes scientific information on the pattern of vegetation change in human-disturbed habitats in the geographical area considered.     

Vegetation dynamics of Mediterranean shrublands in former cultural landscape at Grazalema Mountains,South Spain

Plant community dynamics in Mediterranean basin ecosystems are mainly driven by an alternation of episodes of human intervention and land abandonment. As a result, a mosaic of plant communities has evolved following different stages of degradation and regeneration. Some authors has relate secondary succession to abandoned culture lands and regeneration to natural systems with abandonment of livestock or forestry exploitation. In this paper, the dynamics of shrublands in mid-mountain areas in the South of Spain after disturbance and land abandonment has been studied. The plant cover and 13 environmental variables of 137 selected sites on the Grazalema mountains was analysed to determine the vegetation pattern in relation to environmental factors and the succession types, either regenerative or secondary succession. The results show that today the Grazalema mountains have a heterogeneous vegetation pattern. Besides physical factors such as altitude or soil , human disturbance has modulated current vegetation patterns and dynamics. Two main types of vegetation dynamics can be distinguished in the study area. In areas affected by cutting, regeneration results in rich and dense shrub land, with resprouters as dominant species. In areas affected by recurrent wildfires or agriculture, secondary succession became dominant, resulting in less diverse shrubland, due to the dominance of seeders and decrease in resprouter species richness and cover.     

The relative roles of environment and history as controls of tree species composition and richness in Europe

Aim This study investigates the determinants of European‐scale patterns in tree species composition and richness, addressing the following questions: (1) What is the relative importance of environment and history? History refers to lasting effects of past large‐scale events and time‐dependent cumulative effects of ongoing processes, notably dispersal limited range dynamics. (2) Among the environmental determinants, what is the relative importance of climate, soils, and forest cover? (3) Do the answers to questions 1 and 2 differ between conifers and Fagales, the two major monophyletic groups of European trees? Location The study area comprises most of Europe (34° N–72° N and 11° W–32° E). Methods Atlas data on native distributions of 54 large tree species at 50 × 50 km resolution were linked with climatic, edaphic, and forest cover maps in a geographical information system. Unconstrained (principal components analysis using Hellinger distance transformation and detrended correspondence analysis) and constrained ordinations (redundancy analysis using Hellinger distance transformation and canonical correspondence analysis) and multiple linear regressions were used to investigate the determinants of species composition and species richness, respectively. History is expected to leave its mark as broad spatial patterns and was represented by the nine spatial terms of a cubic trend surface polynomial. Results The main floristic pattern identified by all ordinations was a latitude‐temperature gradient, while the lower axes corresponded mostly to spatial variables. Partitioning the floristic variation using constrained ordinations showed the mixed spatial‐environmental and pure spatial fractions to be much greater than the pure environmental fraction. Biplots, forward variable selection, and partial analyses all suggested climatic variables as more important floristic determinants than forest cover or soil variables. Tree species richness peaked in the mountainous regions of East‐Central and Southern Europe, except the Far West. Variation partitioning of species richness found the mixed spatial‐environmental and pure spatial fractions to be much greater than the pure environmental fraction for all species combined and Fagales, but not for conifers. The scaled regression coefficients indicated climate as a stronger determinant of richness than soils or forest cover. While the dominant patterns were similar for conifers and Fagales, conifers exhibited less predictable patterns overall, a smaller pure spatial variation fraction relative to pure environmental fraction, and a greater relative importance of climate; all differences being more pronounced for species richness than for species composition. Main conclusions The analyses suggest that history is at least as important as current environment in controlling species composition and richness of European trees, with the exception of conifer species richness. Strong support for interpreting the spatial patterns as outcomes of historical processes, notably dispersal limitation, came from the observation that many European tree species naturalize extensively outside their native ranges. Furthermore, it was confirmed that climate predominates among environmental determinants of distribution and diversity patterns at large spatial scales. Finally, the particular patterns exhibited by conifers probably reflect greater environmental specialization and greater human impact. These findings warn against expecting the European tree flora to be able track fast future climate changes on its own.     

Plant diversity,species turnover and shifts in functional traits in coastal dune vegetation: Results from permanent plots over a 52‐year period

Question: What is the relationship between plant diversity and species turnover in coastal dune vegetation plots? How is the long‐term change in species composition of vegetation plots related to shifts in functional traits, and what does it tell us about the dominant processes? Location: Coastal dunes, the Netherlands. Methods: Our data set comprised 52 years of vegetation data from 35 permanent plots in grassland/scrub/woodland vegetation. Vegetation dynamics were described in terms of changes in species composition and abundance, and shifts in 13 functional traits related to resources capture and forage quality, regeneration and dispersal. Results: Species turnover in the plots was high, because of local extinction and colonization. Species‐rich plots were more stable in terms of species abundance and composition compared with species‐poor plots. Over time, the plots converged with respect to their abiotic conditions, as reflected by Ellenberg indicator values – indicating that the prevailing process was succession. The high species turnover reflected high invasibility: accordingly, the relative importance of annuals increased. Most newcomer annuals, however, were competitive generalists of little conservation value. The functional trait analysis allowed us to unravel the complexity of effects of disturbances and succession, and yielded information on the processes driving the observed vegetation dynamics. Conclusions: In this study, small‐scale species turnover was negatively related to species diversity, indicating more stability in species‐rich communities. Regarding shifts in trait diversity, unifying filters appeared to be more dominant than diversifying filters. Counteracting this homogenization process poses a challenge for nature management.     

Vegetation convergence during early succession on coal wastes: a 6‐year permanent plot study

Question: Does the course of succession on a coal mine restored by hydroseeding converge with a reference community in terms of species composition and vegetation structure? What is the rate of succession on restored areas? How does the balance between local colonization and extinction rates change during succession? Which species group (native or hydroseeded) determines the successional process? Location: Large reclaimed coal mine in the north of Palencia province, northern Spain (42°50′N, 4°38′W). Methods: Between 2004 and 2009 we monitored annually vascular plant species cover in nine permanent plots (20 m² each) at a restored mine; these plots were structured to account for site aspect (north, south and flat). Three identical permanent plots were established in the surrounding reference community and monitored in 2004 and 2009. We used detrended correspondence analysis to assess successional trends and rates of succession, generalized linear mixed models to derive patterns of vegetation structural changes and turnover through time, and Huisman–Olff–Fresco modelling to illustrate response of individual species through time. Results: The three restored mine areas exhibited a successional trend towards the reference community through time, although speed of convergence differed. However, after 6 years the restored sites had diverged considerably and this was greater than the dissimilarity reduction with respect to the reference community. Richness, diversity and native species cover increased linearly through time, whereas hydroseeded species cover decreased. Success of hydroseeded species initially differed in the three areas, and this was negatively related with native species colonization rates. Response patterns through time of ten hydroseeded and 20 most common native species are described. Conclusions: Vegetation structural parameters rapidly converged with the reference community, whereas compositional convergence needed much longer. At the same time, successional composition trajectories and rates were related to site properties (here aspect).     

High species diversity and turnover in granite inselberg floras highlight the need for a conservation strategy protecting many outcrops

Determining patterns of plant diversity on granite inselbergs is an important task for conservation biogeography due to mounting threats. However, beyond the tropics there are relatively few quantitative studies of floristic diversity, or consideration of these patterns and their environmental, biogeographic, and historical correlates for conservation. We sought to contribute broader understanding of global patterns of species diversity on granite inselbergs and inform biodiversity conservation in the globally significant Southwest Australian Floristic Region (SWAFR). We surveyed floristics from 16 inselbergs (478 plots) across the climate gradient of the SWAFR stratified into three major habitats on each outcrop. We recorded 1,060 species from 92 families. At the plot level, local soil and topographic variables affecting aridity were correlated with species richness in herbaceous (HO) and woody vegetation (WO) of soil‐filled depressions, but not in woody vegetation on deeper soils at the base of outcrops (WOB). At the outcrop level, bioclimatic variables affecting aridity were correlated with species richness in two habitats (WO and WOB) but, contrary to predictions from island biogeography, were not correlated with inselberg area and isolation in any of the three habitats. Species turnover in each of the three habitats was also influenced by aridity, being correlated with bioclimatic variables and with interplot geographic distance, and for HO and WO habitats with local site variables. At the outcrop level, species replacement was the dominant component of species turnover in each of the three habitats, consistent with expectations for long‐term stable landscapes. Our results therefore highlight high species diversity and turnover associated with granite outcrop flora. Hence, effective conservation strategies will need to focus on protecting multiple inselbergs across the entire climate gradient of the region.     

Latitudinal and altitudinal patterns of plant community diversity on mountain summits across the tropical Andes

The high tropical Andes host one of the richest alpine floras of the world, with exceptionally high levels of endemism and turnover rates. Yet, little is known about the patterns and processes that structure altitudinal and latitudinal variation in plant community diversity. Herein we present the first continental‐scale comparative study of plant community diversity on summits of the tropical Andes. Data were obtained from 792 permanent vegetation plots (1 m²) within 50 summits, distributed along a 4200 km transect; summit elevations ranged between 3220 and 5498 m a.s.l. We analyzed the plant community data to assess: 1) differences in species abundance patterns in summits across the region, 2) the role of geographic distance in explaining floristic similarity and 3) the importance of altitudinal and latitudinal environmental gradients in explaining plant community composition and richness. On the basis of species abundance patterns, our summit communities were separated into two major groups: Puna and Páramo. Floristic similarity declined with increasing geographic distance between study‐sites, the correlation being stronger in the more insular Páramo than in the Puna (corresponding to higher species turnover rates within the Páramo). Ordination analysis (CCA) showed that precipitation, maximum temperature and rock cover were the strongest predictors of community similarity across all summits. Generalized linear model (GLM) quasi‐Poisson regression indicated that across all summits species richness increased with maximum air temperature and above‐ground necromass and decreased on summits where scree was the dominant substrate. Our results point to different environmental variables as key factors for explaining vertical and latitudinal species turnover and species richness patterns on high Andean summits, offering a powerful tool to detect contrasting latitudinal and altitudinal effects of climate change across the tropical Andes.     

Small-scale plant species distribution in snowbeds and its sensitivity to climate change

Alpine snowbeds are characterized by a long-lasting snow cover and low soil temperature during the growing season. Both these key abiotic factors controlling plant life in snowbeds are sensitive to anthropogenic climate change and will alter the environmental conditions in snowbeds to a considerable extent until the end of this century. In order to name winners and losers of climate change among the plant species inhabiting snowbeds, we analyzed the small-scale species distribution along the snowmelt and soil temperature gradients within alpine snowbeds in the Swiss Alps. The results show that the date of snowmelt and soil temperature were relevant abiotic factors for small-scale vegetation patterns within alpine snowbed communities. Species richness in snowbeds was reduced to about 50% along the environmental gradients towards later snowmelt date or lower daily maximum temperature. Furthermore, the occurrence pattern of the species along the snowmelt gradient allowed the establishment of five species categories with different predictions of their distribution in a warmer world. The dominants increased their relative cover with later snowmelt date and will, therefore, lose abundance due to climate change, but resist complete disappearance from the snowbeds. The indifferents and the transients increased in species number and relative cover with higher temperature and will profit from climate warming. The snowbed specialists will be the most suffering species due to the loss of their habitats as a consequence of earlier snowmelt dates in the future and will be replaced by the avoiders of late-snowmelt sites. These forthcoming profiteers will take advantage from an increasing number of suitable habitats due to an earlier start of the growing season and increased temperature. Therefore, the characteristic snowbed vegetation will change to a vegetation unit dominated by alpine grassland species. The study highlights the vulnerability of the established snowbed vegetation to climate change and requires further studies particularly about the role of biotic interactions in the predicted invasion and replacement process.     

Fire severity mediates climate‐driven shifts in understorey community composition of black spruce stands of interior Alaska

Question: How do pre‐fire conditions (community composition and environmental characteristics) and climate‐driven disturbance characteristics (fire severity) affect post‐fire community composition in black spruce stands? Location: Northern boreal forest, interior Alaska. Methods: We compared plant community composition and environmental stand characteristics in 14 black spruce stands before and after multiple, naturally occurring wildfires. We used a combination of vegetation table sorting, univariate (ANOVA, paired t‐tests), and multivariate (detrended correspondence analysis) statistics to determine the impact of fire severity and site moisture on community composition, dominant species and growth forms. Results: Severe wildfires caused a 50% reduction in number of plant species in our study sites. The largest species loss, and therefore the greatest change in species composition, occurred in severely burned sites. This was due mostly to loss of non‐vascular species (mosses and lichens) and evergreen shrubs. New species recruited most abundantly to severely burned sites, contributing to high species turnover on these sites. As well as the strong effect of fire severity, pre‐fire and post‐fire mineral soil pH had an effect on post‐fire vegetation patterns, suggesting a legacy effect of site acidity. In contrast, pre‐fire site moisture, which was a strong determinant of pre‐fire community composition, showed no relationship with post‐fire community composition. Site moisture was altered by fire, due to changes in permafrost, and therefore post‐fire site moisture overrode pre‐fire site moisture as a strong correlate. Conclusions: In the rapidly warming climate of interior Alaska, changes in fire severity had more effect on post‐fire community composition than did environmental factors (moisture and pH) that govern landscape patterns of unburned vegetation. This suggests that climate change effects on future community composition of black spruce forests may be mediated more strongly by fire severity than by current landscape patterns. Hence, models that represent the effects of climate change on boreal forests could improve their accuracy by including dynamic responses to fire disturbance.     

The Importance of Biotic vs. Abiotic Drivers of Local Plant Community Composition Along Regional Bioclimatic Gradients

We assessed if the relative importance of biotic and abiotic factors for plant community composition differs along environmental gradients and between functional groups, and asked which implications this may have in a warmer and wetter future. The study location is a unique grid of sites spanning regional-scale temperature and precipitation gradients in boreal and alpine grasslands in southern Norway. Within each site we sampled vegetation and associated biotic and abiotic factors, and combined broad- and fine-scale ordination analyses to assess the relative explanatory power of these factors for species composition. Although the community responses to biotic and abiotic factors did not consistently change as predicted along the bioclimatic gradients, abiotic variables tended to explain a larger proportion of the variation in species composition towards colder sites, whereas biotic variables explained more towards warmer sites, supporting the stress gradient hypothesis. Significant interactions with precipitation suggest that biotic variables explained more towards wetter climates in the sub alpine and boreal sites, but more towards drier climates in the colder alpine. Thus, we predict that biotic interactions may become more important in alpine and boreal grasslands in a warmer future, although more winter precipitation may counteract this trend in oceanic alpine climates. Our results show that both local and regional scales analyses are needed to disentangle the local vegetation-environment relationships and their regional-scale drivers, and biotic interactions and precipitation must be included when predicting future species assemblages.     

Agriculture erases climate‐driven β‐diversity in Neotropical bird communities

Earth is experiencing multiple global changes that will, together, determine the fate of many species. Yet, how biological communities respond to concurrent stressors at local‐to‐regional scales remains largely unknown. In particular, understanding how local habitat conversion interacts with regional climate change to shape patterns in β‐diversity—differences among sites in their species compositions—is critical to forecast communities in the Anthropocene. Here, we study patterns in bird β‐diversity across land‐use and precipitation gradients in Costa Rica. We mapped forest cover, modeled regional precipitation, and collected data on bird community composition, vegetation structure, and tree diversity across 120 sites on 20 farms to answer three questions. First, do bird communities respond more strongly to changes in land use or climate in northwest Costa Rica? Second, does habitat conversion eliminate β‐diversity across climate gradients? Third, does regional climate control how communities respond to habitat conversion and, if so, how? After correcting for imperfect detection, we found that local land‐use determined community shifts along the climate gradient. In forests, bird communities were distinct between sites that differed in vegetation structure or precipitation. In agriculture, however, vegetation structure was more uniform, contributing to 7%–11% less bird turnover than in forests. In addition, bird responses to agriculture and climate were linked: agricultural communities across the precipitation gradient shared more species with dry than wet forest communities. These findings suggest that habitat conversion and anticipated climate drying will act together to exacerbate biotic homogenization.     

Floristic diversity of an eastern Mediterranean dwarf shrubland: the importance of soil pH

Questions: Does plant species richness and composition of eastern Mediterranean dwarf shrubland (phrygana) correlate with soil pH? How important is the effect of pH on species diversity in relation to other environmental factors in this ecosystem? What is the evolutionary background of the diversity–pH relationship? Location: Western Crete, Greece. Methods: Species composition of vascular plants, soil and other environmental variables were sampled in 100‐m² plots on acidic and basic bedrock in phrygana vegetation. The relationships between species composition and environmental variables (including climate) were tested using canonical correspondence analysis, and relationships between species richness and environment using correlation and regression analyses. Data were analysed separately for different plant functional types based on life form and life span. Results: Although soil pH varied across a narrow range (5.9‐8.1), species composition changed significantly along the pH gradient within all plant functional types. For most functional types, the effect of soil pH on species composition was stronger than that of other environmental variables. Species richness of annuals, geophytes and suffruticose chamaephytes increased with soil pH, while richness of hemicryptophytes and shrubs was not correlated with pH. Conclusions: The results are consistent with the evolutionary species pool hypothesis. High numbers of calcicole annuals, geophytes and suffruticose chamaephytes may be a result of the evolution of these groups on base‐rich dry soils in the Mediterranean climate. In contrast, hemicryptophytes, a life form typical of the temperate zone, evolved on both acidic and basic soils and therefore their species numbers do not respond to soil pH across the narrow range studied. The lack of a relationship between shrub species richness and pH is difficult to explain: it may reflect the more diverse or older origin of Mediterranean woody species and their conservative niches.     

Spontaneous vegetation succession in disused gravel‐sand pits: Role of local site and landscape factors

Questions : What is the variability of succession over a large geographical area? What is the relative importance of (1) local site factors and (2) landscape factors in determining spontaneous vegetation succession? Location : Various regions of the Czech Republic, Central Europe. The regions represent two categories characterized by agrarian lowlands, with a relatively warm and dry climate, and predominant woodland uplands with a relatively cold and wet climate. Methods : Gravel‐sand pits ranged in age from 1–75 years since abandonment. Three types of sites were distinguished: dry, wet and hydric in shallow flooded sites. Vegetation relevés were recorded with species cover (%) visually estimated using the space‐for‐time substitution approach. Local site factors, such as water table and soil characteristics, and landscape characteristics, namely climatic parameters, presence of nearby (semi‐) natural plant communities and main land cover categories in the wider surroundings, were evaluated. Results : Ordination analyses showed that water table was the most important local site factor influencing the course of spontaneous vegetation succession. Succession was further significantly influenced by soil texture, pH, macroclimate, the presence of some nearby (semi‐) natural communities and some land cover categories in the wider surroundings. Spontaneous vegetation succession led to the formation of either shrubby grassland, deciduous woodland, alder and willow carrs, and tall sedge or reed and Typha beds in later stages depending predominantly on the site moisture conditions. Conclusions: Although the water table was the most influential on the course of vegetation succession, the landscape factors together explained more vegetation variability (44%) than local site factors (23%).     

Rate of succession in restored wetlands and the role of site context

Question: Are changes in plant species composition, functional group composition and rates of species turnover consistent among early successional wetlands, and what is the role of landscape context in determining the rate of succession? Location: Twenty‐four restored wetlands in Illinois, USA. Methods: We use 4 years of vegetation sampling data from each site to describe successional trends and rates of species turnover in wetlands. We quantify: (1) the rate at which composition changes from early‐successional to late‐successional species and functional groups, as indicated by site movement in ordination space over time, and (2) the rate of change in the colonization and local extinction of individual species. We correlate the pace of succession to site area, isolation and surrounding land cover. Results: Some commonalities in successional trends were evident among sites. Annual species were replaced by clonal perennials, and colonization rates declined over time. However, differences among sites outweighed site age in determining species composition, and the pace of succession was influenced by a site's landscape setting. Rates of species turnover were higher in smaller wetlands. In addition, wetlands in agricultural landscapes underwent succession more rapidly, as indicated by a rapid increase in dominance by late‐successional plants. Conclusions: Although the outcome of plant community succession in restored wetlands was somewhat predictable, species composition and the pace of succession varied among sites. The ability of restoration practitioners to accelerate succession through active manipulation may be contingent upon landscape context.