Phytosociological Database Research Articles

Pollinator community and generalisation of pollinator spectra changes with plant niche width and local dominance

Abstract Floral traits are assumed to be the main determinants of plant's pollinator spectrum, yet a majority of temperate plant species possess traits allowing to a certain degree of generalisation of their pollinator spectrum. The actual level of pollinator spectrum generalisation is likely to be the result of both plant floral traits and the diversity and abundance of plant species a plant co‐occurs with. We expect that plant species co‐occurring in highly diverse plant communities should host more generalised pollinator spectra. In the present study, we explore the degree to which the composition and generalisation of plant–pollinator spectra depend on the plant's niche width (measured as co‐occurrence with other plant species) and its local dominance (as measured by mean cover in the community). For this purpose, we compiled a database of >250 plant species pollinator spectra from the literature and coupled it with data on plant niche width and local dominance based on the Czech National Phytosociological Database. Species with wider niches had on average more generalised pollinator spectra, ranging from bumblebee‐dominated spectra to diptera‐ and/or nitidulid beetle‐dominated spectra, which was strongly related to plant phylogeny. Plants with bumblebee‐dominated spectra had neither wide niches nor niche specialists. The majority of plants had either muscid‐, hoverfly‐ or nitidulid‐dominated or completely generalised pollinator spectra. Among such plants, higher local dominance increased the proportion of opportune muscids in pollinator spectrum, while hoverflies showed the opposite pattern. Honeybees although rather infrequent in pollinator spectra also showed a strong preference for locally dominant plant species. Synthesis: The composition of a plant's pollinator spectrum is not independent of other aspects of the plant's life history, namely niche width and the ability to dominate the community. Wider plant species niches result in more generalised pollinator spectra, supporting our hypothesis that habitat generalists are less prone to specialisation on particular pollinator groups. Conversely, the ability to dominate local plant communities influenced pollinator spectra mainly through specific responses of individual pollinator groups. Read the free Plain Language Summary for this article on the Journal blog.

Ability of plant species to colonise human‐disturbed habitats: Role of phylogeny and functional traits

AbstractQuestionWhich species are successful colonisers of disturbed sites; species adapted to seed dispersal, resistance to abiotic stress, or competition ability? Are successful adaptations for colonisation shared by phylogenetically related species?LocationCzech Republic, Central Europe.MethodsWe used two indices of plant species’ colonisation ability (developed from an extensive dataset of dated successional series for 1,531 plant species of the Czech Republic): index of colonisation potential (ICP), which is corrected for mass effect (species’ frequency in the landscape acquired from Czech National Phytosociological Database, accounting for more common colonisation events of frequent species), and index of colonisation success (ICS), which is solely based on actual species frequencies in disturbed habitats. We also used preferences for successional age (median of age of sites that species had colonised). We correlated these indices with plant functional traits for three functional groups (woody species, non‐woody perennial polycarpic, and non‐woody monocarpic species) either considering the phylogenetic history of a species or not.ResultsWoody species were the best colonisers and had the highest preferences for late‐successional stages. Non‐woody monocarpic species had a higher ICP than polycarpic species while their ICS were comparable. The best predictor of colonisation ability of both monocarpic and polycarpic non‐woody species was canopy height, indicating importance of competition. Other successful colonisers were species with seed traits promoting dispersal (low seed mass or low seed terminal velocity). We did not find traits suitable for adverse biotic conditions (high specific leaf area, SLA), low canopy height) to be important. Successional age preference of species was indicated mainly by seed traits (seed mass, seed longevity), which highly corresponded with species’ phylogenetic history.ConclusionsColonisation of disturbed sites is limited by seed dispersal and competitive interactions rather than an adverse abiotic environment.

Herbaceous climbers in herbaceous systems are shade‐tolerant and magnesium‐demanding

AbstractQuestionsClimbers do not invest in self‐supporting architecture, allowing them to grow quickly and search for light and nutrients in canopy gaps. The climbing strategy requires both disturbance and external support; however, in herbaceous systems, disturbances often homogeneously remove external support. As a result, there should be a negative relationship between light availability and the presence of external support. Here, we asked if the distribution of herbaceous climbers is positively or negatively associated with disturbance, light availability and plant‐available nutrients. Further, we tested if climbers differ in traits compared to co‐occurring herbs.LocationCzech Republic.MethodsWe used observations from a phytosociological database, species‐rich grasslands and arable fields. First, we examined the presence of climbers in response to disturbance variables (frequency, severity and regime) and canopy cover (external support and light availability). Second, we examined the distribution of climbers along gradients of plant‐available nutrients in species‐rich grasslands. Finally, we compared seven functional traits between 31 climbers and 1,138 co‐occurring herbs growing in 18 Central European herbaceous habitats.ResultsWe found no relationship between any disturbance variables and the occurrence of climbers; indeed, climbers tended to occur more frequently in sites with denser canopies. In species‐rich grasslands, the presence of climbers was positively related to plant‐available magnesium. Climbers tended to be taller, with greater seed mass and specific leaf area (SLA) than co‐occurring species.ConclusionsHerbaceous climbers grow in plots with low light availability but plenty of external support and require magnesium for the formation of flexible stems. Compared to co‐occurring herbs, climbers allocate resources saved from their lack of self‐support to both shade‐avoidance (canopy height) and shade‐tolerance traits (seed mass, SLA). Compared to lianas, the distribution of herbaceous climbers is not affected by disturbance but is dependent on the availability of external support and magnesium.

Ecological specialization indices for species of the Czech flora

Theoretically the concept of species ecological specialization is very useful, however, practically it is often difficult to quantify due to a lack of relevant environmental data. We introduce the Ecological Specialization Index (ESI), which describes the degree of specialization of a species based on its realized niche along multiple environmental gradients and is conceptually based on the co-occurrence specialization metric theta introduced by Fridley et al. (2007). We estimated ESI for species of the Czech flora occurring in at least 10 vegetation plots stored in the Czech National Phytosociological Database. We prepared three sets of ESI values calculated from three datasets including (i) plots of all vegetation types (ESIw, 1597 species), (ii) only plots of non-forest vegetation (ESInf, 1529 species), and (iii) only plots of forest vegetation (ESIf, 881 species). We also provide the frequency of species in the datasets, since the reliability of the calculated ESI values increases with the species frequency. The use of these ESI values is limited to the Czech Republic, and in the case of less frequent species, the value can be influenced by sampling bias. To facilitate understanding of the ecological meaning of ESI, we related the calculated values of ESIw to several species attributes and applied them in a case study using a local vegetation dataset from a deep river valley. We found that ESI correlates significantly with specialization metrics based on the number of phytosociological associations and habitats in which the focal species occur. The species listed in the national Red List in higher risk categories are on average more specialized than less threatened species. Neophytes tend to be significantly less specialized than archaeophytes and native species. When related to Ellenberg-type indicator values for the Czech Republic, specialists tend to be more shade-tolerant, better adapted to nutrient-poor soils and soils with either a low or high (but not intermediate) pH and to either warm or cold (but not intermediate) habitats. In a case study of herbaceous plants species in a forest understory on river valley slopes, we found that specialists tend to be confined to deeper soils on cooler north-facing slopes, to stony soils in ravine forests and sites with a denser canopy of woody species. In contrast, shallow lithic soils on eroded south-facing slopes and sites with a more open canopy tend to be dominated by generalists. The complete list of ESI values is included in an electronic appendix to this paper.

A novel method to predict dark diversity using unconstrained ordination analysis

AbstractQuestionsSpecies pools are the product of complex ecological and evolutionary mechanisms, operating over a range of spatial scales. Here, we focus on species absent from local sites but with the potential to establish within communities — known as dark diversity. Methods for estimating dark diversity are still being developed and need to be compared, as well as tested for the type, and amount, of reference data needed to calibrate these methods.LocationSouth Bohemia (48°58′ N, 14°28′ E) and Železné Hory (49°52′ N, 15°34′ E), Czech Republic.MethodWe compared a widely accepted algorithm to estimate species pools (Beals smoothing index, based on species co‐occurrence) against a novel method based on an unconstrained ordination (UNO). Following previous work, we used spatially nested sampling for target plots, with the dark diversity estimates computed from smaller plots validated against additional species present in larger plots, and a reference dataset (Czech National Phytosociological Database of >30,000 plots as global reference data). We determined which method provides the best estimate of dark diversity with an index termed the “Success Rate Index”.ResultsWhen using the whole reference dataset (national scale), both UNO and Beals provided comparable predictions of dark diversity that were better than null expectations based on species frequency. However, when predicting from regionally restricted spatial scales, UNO performed significantly better than Beals. UNO also tended to detect less common species better than Beals. The success rate of combining UNO and Beals slightly outperformed the results obtained from the single methods, but only with the largest reference dataset.ConclusionsThe UNO method provides a consistently reliable estimate of dark diversity, particularly when the reference dataset is size‐limited. For future calculations, we urge caution regarding the choice of dark diversity methods with respect to the reference data available, and how different methods handle species of high, and low, occurrence frequency.

Ancient refugia and present‐day habitat suitability of native laurophylls in Italy

AbstractQuestionsEuropean native laurophyllous species are interesting for their biogeography and evolutionary history, as well as for their responses to global changes. We identified Italian native laurophylls on the basis of morphology, biogeographical history and ecological niche to study whether these species are in equilibrium with the present‐day climate. Furthermore, we localized Quaternary refugia and areas of potential spread of native laurophylls using distribution patterns of realized and potential aggregations of native laurophylls, respectively.LocationItaly.MethodsWe extracted data for 17 087 forest plots from a phytosociological database. Detrended Correspondence Analysis of these plots with overlay of climatic and environmental variables was performed to identify native laurophylls, i.e., evergreen broad‐leaved species of late Tertiary radiation, occupying a warm and humid niche. Potential ranges of laurophylls were calculated using Beals’ index of sociological favourability. The realized/potential range‐size ratio was calculated for each single laurophyll to understand whether it is in equilibrium with the present‐day climate. Distribution patterns of realized and potential aggregations of laurophylls were mapped.ResultsOrdination analysis provided a selection of 11 species as Italian native laurophylls. Most of them occupied less than half of their estimated potential range. Realized aggregations richest in native laurophylls were localized in the central Apennines. However, the Italian forests showed high potential for native laurophylls with the richest potential aggregations in the whole Apennines and in the southern Alps.ConclusionsMost of the Italian native laurophylls showed non‐equilibrium with the current climate, suggesting that late‐Quaternary events could better explain their present‐day distribution than on‐going climate change. Furthermore, their refugia in central Italy suggest the persistence in sites with temperate climate during Quaternary environmental changes. The high suitability of Italian forests for laurophylls, along with global changes, suggests possible future spreading of these species.

Temporal niche differentiation among species changes with habitat productivity and light conditions

AbstractAimNiche differentiation along the temporal axis has often been suggested as a potential mechanism of species coexistence. Species may co‐occur by shifting timing of growth, or by changing their growth rate to avoid competition for resources, namely light. However, due to the lack of data on growth phenology of a large set of species, we do not know how common each phenomenon is and whether the phenology of coexisting species shows a non‐random distribution, which would be indicative of either niche differentiation or resource competition.LocationCzech Republic.MethodsWe recorded growth phenological data of 381 perennial herbaceous species in plant collections in the Botanical Garden of Charles University in Prague, allowing frequent recordings on a large number of species that grow in conditions close to their natural habitats. We used the measurements to derive the day of peak growth and two types of growth rates. We then used co‐occurrence data of these species from the Czech National Phytosociological Database and examined whether co‐occurring species show non‐random patterns of these parameters in 11 individual habitats, which were identified by the European Nature Information System.ResultsWe found large differences among habitat types, partly due to differences in habitat productivity, indicated by the mean height and summed cover of all species in the habitats. Unexpectedly, we did not find temporal niche differentiation in woodlands, indicating the day of peak growth of species was essentially random. Growth rates in forests were strongly over‐dispersed. This pattern contrasted with grasslands where the distribution of all parameters showed synchronization, which is likely because plants need to succeed in asymmetric competition for light.ConclusionThese data provide the first quantitative assessment of differences in growth dynamics across communities and show one of the first unequivocal demonstrations of trait overdispersion in plant communities.

Ellenberg-type indicator values for the Czech flora

A new dataset of ecological indicator values for species, subspecies and some varieties, hybrids and infrageneric species groups has been compiled for the vascular flora of the Czech Republic. Indicator values for light, temperature, moisture, (soil) reaction, nutrient availability and salinity were assigned to 2275 species and 801 other taxa, using the nine-degree (or 12-degree for moisture and 10-degree for salinity) ordinal scales proposed by Heinz Ellenberg for the flora of Germany. The values are compatible with Ellenberg indicator values, which were used as a baseline, but extensively revised based on our own field observations, literature, comparison with indicator value systems of other countries and an analysis of taxon co-occurrences in vegetation plots from the Czech National Phytosociological Database. Taxa in the Czech flora missing in the original Ellenberg tables were added. Compared with the original Ellenberg's dataset of indicator values, smaller proportions of taxa were classified as extremely basiphilous, extremely oligotrophic or strictly avoiding saline habitats. The revised values were tested by regressing unweighted site mean indicator values against measured environmental variables. In most cases, prediction of environmental conditions was slightly more accurate with the new Czech indicator values than with the original Ellenberg indicator values. The full dataset of indicator values is available in an electronic appendix to this paper.

National vegetation classification of the Czech Republic: a summary of the approach

Aim: To describe the classification approach and protocols that were used in the project Vegetation of the Czech Republic and relate them to the comparative framework for broad-scale plot-based vegetation classification proposed by De Caceres et al. (2015). This description should facilitate comparison of this national vegetation classification with vegetation classifications in other countries. - Location: Czech Republic. - Methods: The project Vegetation of the Czech Republic, realized from 1997 to 2013, was based on the analyses of vegetation-plot records from the Czech National Phytosociological Database. Associations were defined as the basic hierarchical level using formal definitions created with the Cocktail method. These formal definitions were included in a computer expert system for automatic identification of associations. Evaluation and characterization of associations were based on the groups of plot records assigned to the particular associations by the expert system. Higher classification levels were classified by type-based grouping of associations. A novel statistical method for determining diagnostic species of vegetation types was developed within the project. All the analytical procedures used and developed for the project were included in the JUICE program. - Results: The national vegetation classification system was published in a four-volume monograph from 2007 to 2013. It consists of five hierarchical levels with nested vegetation types, including 9 formations, 39 classes, 138 alliances, 496 associations and for some associations also variants. At the same time the project infrastructure, including the expert system and the JUICE program, was published online. - Conclusions: The national vegetation classification of the Czech Republic provided novel classification approach and protocols. Several elements of these protocols have been subsequently applied in other countries. At the national level, the classification has found various applications both in nature conservation and in basic research.

Habitat conditions, stage structure and vegetation associations of geographically isolated subalpine populations of Salix lapponum L. (Salicaceae) in the Krkonoše Mts (Czech Republic)

Shrub communities are important components of the subalpine vegetation. We focused on habitat conditions and stage structure (flowering and non-reproducing individuals) of stands of the endangered Salix lapponum in the Krkonose Mts, Czech Republic. Habitat conditions were determined using soil sample analyses and Ellenberg indicator values (EIVs) derived from fine-scale (1 × 1 m) vegetation plots. The fine-scale plots were compared with coarse-scale releves with the occurrence of S. lapponum acquired from the Czech National Phytosociological Database. We found that S. lapponum grows on nutrient-poor, acidic soils with high relative water contents, high amounts of total nitrogen, low amounts of phosphorus, moderate amounts of magnesium and low to moderate amounts of calcium. The overall proportion of non-reproducing individuals was 35.2%, but strong variations were observed among populations (0–100%). Co-occurring species and EIVs data indicated that flowering individuals are relatively more common in humid, nutrient-rich and warmer microhabitats than non-reproducing ones. Well-developed (“typical”) stands of S. lapponum with a dominance of flowering individuals occur along alpine springs, streams and in glacial cirques (= association Salicetum lapponum Zlatnik 1928), but S. lapponum also grows along transitional mires and peat bogs and in subalpine grasslands. Coarse-scale releves were similar to “typical” stands of S. lapponum at the fine scale but were differentiated from them by high frequencies of several, mainly broad-leaved forbs and herbs typical of moist to wet and fertile soils. Threats to S. lapponum and the future prospects of its stands in the Krkonose Mts are briefly discussed.

High-resolution and large-extent mapping of plant species richness using vegetation-plot databases

The recent increase in the availability of large vegetation-plot databases has created unprecedented opportunities for analysing and explaining patterns of fine-scale plant species richness across large areas and for individual habitat types. Here we demonstrate how these data can be used to (1) prepare country-wide high-resolution maps of species richness and identify national diversity hotspots for grassland and forest vegetation; (2) compare diversity patterns of all, native, alien and Red List species; and (3) identify potential environmental drivers of these patterns. At the same time we examine and quantify the stability of predicted species-richness patterns with respect to the most common biases that are inherent to large vegetation-plot databases. Vegetation-plot records were obtained from the Czech National Phytosociological Database and the Random Forest method was used to map fine-scale spatial diversity patterns of all, native, alien and Red List vascular plant species, separately for grasslands and forests across the Czech Republic. The stability of the predicted species-richness patterns was tested using differently resampled datasets in which we either reduced or increased local oversampling and preferential sampling of more species-rich communities. Models for grassland and forest vegetation explained 40–65% of variation in fine-scale species richness. Spatial patterns of all and native species richness differed considerably between grasslands and forests, whereas alien and Red List species showed a higher congruence between these two vegetation types. Patterns of modelled species richness were highly stable with respect to all resampling strategies applied to the initial datasets. We conclude that vegetation-plot databases are a valuable source of data for high-resolution mapping of the plant species richness of different vegetation types and species groups, because each of them can exhibit a different diversity pattern. The resulting maps provide robust representation of the spatial patterns of fine-scale species richness and can be used both for testing scientific hypotheses about the controls of diversity patterns and for conservation planning.

Beta‐diversity of central European forests decreases along an elevational gradient due to the variation in local community assembly processes

Beta‐diversity has been repeatedly shown to decline with increasing elevation, but the causes of this pattern remain unclear, partly because they are confounded by coincident variation in alpha‐ and gamma‐diversity. We used 8795 forest vegetation‐plot records from the Czech National Phytosociological Database to compare the observed patterns of beta diversity to null‐model expectations (beta‐deviation) controlling for the effects of alpha‐ and gamma‐diversity. We tested whether β‐diversity patterns along a 1200 m elevation gradient exclusively depend on the effect of varying species pool size, or also on the variation of the magnitude of community assembly mechanisms determining the distribution of species across communities (e.g. environmental filtering, dispersal limitation). The null model we used is a novel extension of an existing null‐model designed for presence/absence data and was specifically designed to disrupt the effect of community assembly mechanisms, while retaining some key features of observed communities such as average species richness and species abundance distribution. Analyses were replicated in ten subregions with comparable elevation ranges. Beta‐diversity declined along the elevation gradient due to a decrease in gamma‐diversity, which was steeper than the decrease in alpha‐diversity. This pattern persisted after controlling for alpha‐ and gamma‐diversity variation, and the results were robust when different resampling schemes and diversity metrics were used. We conclude that in temperate forests the pattern of decreasing beta‐diversity with elevation does not exclusively depend on variation in species pool size, as has been hypothesized, but also on variation in community assembly mechanisms. The results were consistent across resampling schemes and diversity measures, thus supporting the use of vegetation‐plot databases for understanding patterns of beta‐diversity at the regional scale.

Participation of the Czech flora in succession at disturbed sites

The colonization of newly created sites by plants is determined by the characteristics of the species and their frequency in the surrounding landscape (mass effect). We used species frequencies from the Database of Successional Series of various disturbed sites across the Czech Republic (DaSS, 2817 phytosociological releves, 1013 species of vascular plants) to calculate two indices of species colonization ability. One index (index of colonization potential - ICP) was corrected using occurrence data in the Czech National Phytosociological Database (CNPD) and the other (index of colonization success - ICS) was used without correction. We also evaluated the participation of species in successional stages of different ages and assessed their maximum cover. Then we asked, species of which habitat types are the most successful in colonizing disturbed sites and how their participation changes over the course of succession. Species characteristic of the following habitat types were statistically over-represented in the successional series compared to in the CNPD: synanthropic habitats; cliffs, screes and walls; acidophilous grassland; dry grassland; and sandy grassland. Species characterizing particular types of habitat exhibited significant trends in their participation in different successional stages: those of dry grassland, heathland, scrub land and forest increased during succession whereas species of synanthropic acidophilous grassland, mesic grassland and wetland decreased. Species with high values of both indices are more likely to spread in landscapes continuously disturbed by human activity. Thus, these indices can help to predict future changes in vegetation in central-European landscapes and be used in ecological restoration projects.

Grasslands in the Polish Carpathians – a regional thematic phytosociological database

Grasslands in the Polish Carpathians – a regional thematic phytosociological database

Does succession run towards potential natural vegetation? An analysis across seres

AbstractQuestions(1) Do 17 seres studied proceed towards corresponding potential natural vegetation; (2) what are the similarities between seral and potential natural vegetation, and is it possible to estimate how long it takes to reach potential natural vegetation; and (3) do primary and secondary seres differ?LocationExtracted peatlands, corridors of the former iron curtain, artificial fishpond islands and barriers, sedimentary basins, various spoil heaps after mining, various stone quarries, forest clearings, burned‐down forests, road verges, sand and gravel‐sand pits, river gravel bars and abandoned arable fields located in various parts of the Czech Republic.MethodsSeral stages were sampled by phytosociological relevés (2602). The following categories of successional age were considered: early (1–10 yrs), intermediate (11–25 yrs) and late (>25 yrs). Phytosociological relevés (386) representing corresponding potential natural vegetation were extracted from the National Phytosociological Database. DCA and CCA ordinations were performed to compare the pattern of seral stages with potential natural vegetation and between primary and secondary seres. Dissimilarity between seral stages of primary and secondary successions and the corresponding potential natural vegetation was further assessed using the Bray‐Curtis dissimilarity measure. Extrapolation was performed to estimate when the seres will reach the stage corresponding to potential natural vegetation.ResultsThe ordination showed that successions proceeded towards the corresponding potential natural vegetation and reflected substrate pH, site moisture and successional age. The estimated average time needed to reach potential natural vegetation was about 180 yrs for primary successions and about 260 yrs for secondary successions, considering presence–absence species data, and 200 and 250 yrs, respectively, considering cover data. All species recorded in potential natural vegetation (421) were also recorded in seral vegetation.ConclusionsIn the general view across the high number of seres spread over the whole country, successions advanced in the direction of the corresponding potential natural vegetation. The extrapolated recovery of potential natural vegetation is faster in primary seres than in secondary ones, and seres sooner resemble the corresponding potential natural vegetation in species composition than in vegetation structure.

Online appendix 2:Vegetation of the eastern communal conservancies in Namibia: I. Phytosociological descriptions

The establishment of communal conservancies aims to have the local communities share in the benefits especially of wildlife resources, in this way spearheading the conservation of the environment. The Desert Margins Programme in Namibia aimed to develop vegetation resource data for the Otjituuo, Okamatapati, Ozonahi, African Wild Dog, Otjinene, Epukiro, Otjombinde, Omuramba Ua Mbinda, Eiseb and Ondjou communal conservancies, in order to assist with natural resource planning. For this purpose, a phytosociological survey of this area, with 422 relevés, was conducted during 2004. The data was captured in Turboveg and forms part of the Namibian phytosociological database (GIVD AF-NA-001). The data was split into two, representing two major land forms, the ‘hardeveld’ and the ‘sandveld’, respectively. A classification was undertaken using the Modified two-way indicator species analysis (TWINSPAN) procedure. Further refinements, based on field observations and literature sources, were performed using Cocktail procedures. Thirteen vegetation associations were formally described in this article, of which two were subdivided into subassociations. These associations can broadly be grouped into broad-leaved savanna types typical of the central and northern Kalahari of Namibia and microphyll savannas found on the transitions to the Central Plateau. One association, the Burkeo africanae–Pterocarpetum angolensis, forms the southern fringe of the Zambesian Baikiaea Woodlands ecoregion of the World Wildlife Fund, whilst all the other associations fall within the Kalahari Acacia–BaikiaeaWoodlands ecoregion. The Combreto collini–Terminalietum sericeae is the most widespread association and dominates the landscape. Threats to the vegetation include overutilisation and regular fires, both of which could easily lead to desertification. This threat is aggravated by global climate change.Conservation implications: This article described 13 plant associations of the central Kalahari in eastern Namibia, an area hitherto virtually unknown to science. The information presented in this article forms a baseline description, which can be used for future monitoring of the vegetation under communal land use.

Online appendix 1:Vegetation of the eastern communal conservancies in Namibia: I. Phytosociological descriptions

The establishment of communal conservancies aims to have the local communities share in the benefits especially of wildlife resources, in this way spearheading the conservation of the environment. The Desert Margins Programme in Namibia aimed to develop vegetation resource data for the Otjituuo, Okamatapati, Ozonahi, African Wild Dog, Otjinene, Epukiro, Otjombinde, Omuramba Ua Mbinda, Eiseb and Ondjou communal conservancies, in order to assist with natural resource planning. For this purpose, a phytosociological survey of this area, with 422 relevés, was conducted during 2004. The data was captured in Turboveg and forms part of the Namibian phytosociological database (GIVD AF-NA-001). The data was split into two, representing two major land forms, the ‘hardeveld’ and the ‘sandveld’, respectively. A classification was undertaken using the Modified two-way indicator species analysis (TWINSPAN) procedure. Further refinements, based on field observations and literature sources, were performed using Cocktail procedures. Thirteen vegetation associations were formally described in this article, of which two were subdivided into subassociations. These associations can broadly be grouped into broad-leaved savanna types typical of the central and northern Kalahari of Namibia and microphyll savannas found on the transitions to the Central Plateau. One association, the Burkeo africanae–Pterocarpetum angolensis, forms the southern fringe of the Zambesian Baikiaea Woodlands ecoregion of the World Wildlife Fund, whilst all the other associations fall within the Kalahari Acacia–BaikiaeaWoodlands ecoregion. The Combreto collini–Terminalietum sericeae is the most widespread association and dominates the landscape. Threats to the vegetation include overutilisation and regular fires, both of which could easily lead to desertification. This threat is aggravated by global climate change.Conservation implications: This article described 13 plant associations of the central Kalahari in eastern Namibia, an area hitherto virtually unknown to science. The information presented in this article forms a baseline description, which can be used for future monitoring of the vegetation under communal land use.

Clonal and bud bank traits: patterns across temperate plant communities

AbstractQuestionsWe examine patterns of clonal traits and below‐ground bud bank traits in plant communities over a large set of temperate vegetation types. We asked (i) how clonal traits are distributed in different community types and (ii) what are within‐community patterns of these traits as an indication of their role in species coexistence and community assembly.LocationCzech Republic.MethodsWe use a stratified set of more than 20,000 vegetation records from the Czech National Phytosociological Database as a source of species co‐occurrence and habitat type data, and combined it with data on clonal and bud bank traits from the CLO‐PLA database. We calculated both community trait means and dispersions for all records in the database and used a series of randomization tests to assess effects of environmental filtering and within‐community assembly.ResultsHabitat filtering was stronger in bud bank traits than in clonal traits. The key factors driving structure of clonal traits in Central Europe seem to be differences in productivity and in wetness. These gradients are responsible for a major change in clonal growth parameters, from clonal plants with short and persistent connections in dry and unproductive habitats to plants with long‐ and short‐lived connections in wet and productive sites. Size of the bud bank is rather uncorrelated with this gradient: species with small below‐ground bud bank size prevail in highly disturbed and in water habitats. None of the traits showed significant overdispersion, either at the level of the whole data set, or at the level of individual habitat types.ConclusionsCapacity for clonal growth occurs under many different environmental regimes and can give rise to very different growth forms. Therefore, using capacity for clonal growth as a proxy for clonal reproduction, capture of horizontal space or resprouting capacity may hinder understanding of its role. Absence of overdispersion after accounting for habitat filtering means that we found no evidence that clonal traits play a role in niche‐based coexistence processes.

Contrasted taxonomic, phylogenetic and functional diversity patterns in semi-natural permanent grasslands along an altitudinal gradient

Background and aims - Recent methodological and theoretical advances in community ecology have allowed more robust exploration of complementary facets of biodiversity in plant communities. Focusing on semi-natural permanent grasslands of the French Jura Mountains, we assessed how taxonomic, phylogenetic and functional diversity metrics vary among three phytosociological vegetation units. Methods - We selected a sample of 135 releves out of a phytosociological database, depicting three phytosociological orders (Brometalia erecti, Arrhenatheretalia elatioris and Trifolio repentis-Phleetalia pratensis) and including 381 vascular plant species. We built a phylogenetic tree based on sequences of two genes encoding chloroplast proteins, from which we computed phylogenetic diversity metrics that we compared to various taxonomic, single-trait and multi-trait functional metrics, including communityweighted means of functional traits (CWMs). Key results - Most diversity metrics and CWMs significantly differed among vegetation units. Within each facet of biodiversity, the different metrics showed complementary results. Moreover, even when considering diversity metrics comparable in mathematical terms, i.e. based on Rao quadratic entropy, the results were largely non-redundant among the facets of biodiversity. Phylogenetic diversity and multi-trait functional diversity show opposite responses to vegetation units, as well as a low phylogenetic signal. These two results suggest that phylogenetic diversity cannot be used as a simple proxy for functional diversity. Conclusion - This study highlights the importance of taking into consideration different facets for a better understanding of biodiversity. In particular, phylogenetic and functional facets appear highly informative, and could thus be used in addition to taxonomic diversity metrics as indicators of conservation value. © 2014 Botanic Garden Meise and Royal Botanical Society of Belgium.

Vegetation of the eastern communal conservancies in Namibia: I. Phytosociological descriptions

The establishment of communal conservancies aims to have the local communities share in the benefits especially of wildlife resources, in this way spearheading the conservation of the environment. The Desert Margins Programme in Namibia aimed to develop vegetation resource data for the Otjituuo, Okamatapati, Ozonahi, African Wild Dog, Otjinene, Epukiro, Otjombinde, Omuramba Ua Mbinda, Eiseb and Ondjou communal conservancies, in order to assist with natural resource planning. For this purpose, a phytosociological survey of this area, with 422 relevés, was conducted during 2004. The data was captured in Turboveg and forms part of the Namibian phytosociological database (GIVD AF-NA-001). The data was split into two, representing two major land forms, the ‘hardeveld’ and the ‘sandveld’, respectively. A classification was undertaken using the Modified two-way indicator species analysis (TWINSPAN) procedure. Further refinements, based on field observations and literature sources, were performed using Cocktail procedures. Thirteen vegetation associations were formally described in this article, of which two were subdivided into subassociations. These associations can broadly be grouped into broad-leaved savanna types typical of the central and northern Kalahari of Namibia and microphyll savannas found on the transitions to the Central Plateau. One association, the Burkeo africanae–Pterocarpetum angolensis, forms the southern fringe of the Zambesian Baikiaea Woodlands ecoregion of the World Wildlife Fund, whilst all the other associations fall within the Kalahari Acacia–BaikiaeaWoodlands ecoregion. The Combreto collini–Terminalietum sericeae is the most widespread association and dominates the landscape. Threats to the vegetation include overutilisation and regular fires, both of which could easily lead to desertification. This threat is aggravated by global climate change.Conservation implications: This article described 13 plant associations of the central Kalahari in eastern Namibia, an area hitherto virtually unknown to science. The information presented in this article forms a baseline description, which can be used for future monitoring of the vegetation under communal land use.