Montane Plant Species Research Articles

Modelling landscape-scale occurrences of common grassland species in a topographically complex mountainous environment

Mountainous regions typically harbour high plant diversity but are also characterised by low sampling intensity. Coarse-scale species distribution models can provide insights into the distribution of poorly sampled species, but the required bioclimatic data are often limited in these landscapes. In comparison, several environmental factors that vary over relatively fine scales in mountain environments (e.g. measures of topography) can be quantified from remotely-sensed data, and can potentially provide direct and indirect measures of biologically-relevant habitat characteristics in mountains. Therefore, in this study, we combine field-sampled floristic data with environmental predictors derived from remotely-sensed data, to model the ecological niches of 19 montane plant species in the Maloti-Drakensberg mountains, South Africa. The resulting models varied considerably in their performance, and species showed generally inconsistent responses to environmental predictors, with altitude and distance to watershed being most frequently included in models. These results highlight the species-specificity of the forb species’ environmental tolerances and requirements, suggesting that environmental change may result in re-shuffling of community composition, instead of intact communities shifting along gradients. Furthermore, while the relatively high importance of altitude (a proxy for temperature) and topographic wetness index (a proxy for soil moisture) suggest that the flora of this region will be sensitive to shifts in temperature and rainfall patterns, several non-climatic environmental variables were also influential. Our findings indicate that local response to climate change in mountains might be especially constrained by soil type and topographic variables, supporting the important influence of non-climatic factors in microclimatic refugia dynamics.

Differences in individual flowering time change pollen limitation and seed set in three montane wildflowers.

Changes to flowering time caused by climate change could affects plant fecundity, but studies that compare the individual-level responses of phenologically distinct, co-occurring species are lacking. We assessed how variation in floral phenology affects the fecundity of individuals from three montane species with different seasonal flowering times, including in snowmelt acceleration treatments to increase variability in phenology. We collected floral phenology and seed set data for individuals of three montane plant species (Mertensia fusiformis, Delphinium nuttallianum, Potentilla pulcherrima). To examine the drivers of seed set, we measured conspecific floral density and conducted pollen limitation experiments to isolate pollination function. We advanced the phenology of plant communities in a controlled large-scale snowmelt acceleration experiment. Differences in individual phenology relative to the rest of the population affected fecundity in our focal species, but effects were species-specific. For our early-season species, individuals that bloomed later than the population peak bloom had increased fecundity, while for our midseason species, simply blooming before or after the population peak increased individual fecundity. For our late-season species, blooming earlier than the population peak increased fecundity. The early and midseason species were pollen-limited, and conspecific density affected seed set only for our early-season species. Our study shows that variation in individual phenology affects fecundity in three phenologically distinct montane species, and that pollen limitation may be more influential than conspecific density. Our results suggest that individual-level changes in phenology are important to consider for understanding plant reproductive success.

Monitoring bumblebee pollinator visits to the medicinal plant Gentiana asclepiadea L. (Gentianacese) – a comparison between the periods 1990–1994 and 2017–2020

Ever increasing data continue to indicate the decline of bumblebee populations. The key factors causing declines in their abundance and diversity are: 1) habitat destruction, 2) loss of floral resources, 3) emerging diseases, 4) increased use of pesticides (particularly neonicotinoids). The aim of this study is to monitor bumblebee visits to Gentiana asclepiadea L, recording pollinator species, and taking measurements of seed set. This plant species is chosen for two reasons: 1) similar data is available from our previous research in the 1990’s and 2) this montane plant species is supposed to be less exposed to hazards from pesticides and habitat destruction. Three study sites were chosen in Mt. Vitosha (SW Bulgaria) where natural populations of G. asclepiadea occur in 1990. The observations of bumblebee activity in the flowers of G. asclepiadea were conducted during the flowering seasons (August and September) of 2017 – 2020 at the same study sites and compared to the data obtained in the previous period (1990–1994). The free pollination fruit set was tested by monitoring of 100 G. asclepiadea flowers each year for development of fruit capsules. The seed set was tested by counting the matured seeds and non-fertilised ovules of 10 fruit capsules each year. A slight decline in bumblebee activity was recorded in 2017 – 2020 in comparison to 1990–1994. This is reflected in the fruit set and the seed set. Our data demonstrates that even in a mountain habitat, where there are fewer direct hazards to bumblebees, that pollination effectiveness has been suppressed over time. This corresponds to a research study which provides evidence that insect biomass fell by 76% in German nature reserves between 1989 and 2016.

Temperature and soils predict the distribution of plant species along the Himalayan elevational gradient

AbstractTropical montane systems are characterized by a high plant species diversity and complex environmental gradients. Climate warming may force species to track suitable climatic conditions and shift their distribution upward, which may be particularly problematic for species with narrow elevational ranges. To better understand the fate of montane plant species in the face of climate change, we evaluated a) which environmental factors best predict the distribution of 277 plant species along the Himalayan elevational gradient in Nepal, and b) whether species elevational ranges increase with increasing elevation. To this end, we developed ecological niche models using MaxEnt by combining species survey and presence data with 19 environmental predictors. Key environmental factors that best predicted the distribution of Himalayan plant species were mean annual temperature (for 54.5% of the species) followed by soil clay content (10.2%) and slope (9.4%). Although temperature is the best predictor, it is associated with many other covariates that may explain species distribution, such as irradiance and potential evapotranspiration. Species at both ends of the Himalayan elevational gradient had narrower elevational ranges than species in the middle. Our results suggest that with further global warming, most Himalayan plant species have to migrate upward, which is especially critical for upland species with narrow distribution ranges.

Vegetation creates microenvironments that influence soil microbial activity and functional diversity along an elevation gradient

Soil microbial communities are responsive to abiotic and biotic conditions within the heterogeneous soil environment. In montane plant communities, vegetation can create distinctive microenvironments that have unique microbial responses. Here, we ask how soil microbial activity and functional diversity were influenced by the type and diversity of montane plant species, and the morphological and chemical traits of their associated root systems, that are expected to influence soil properties. Along an elevational gradient (1400-2400 m a.s.l.) in the French Alps, we investigated microbial global catabolic activity (i.e. microbial activity) and catabolic diversity (i.e. functional diversity) in bulk and rhizosphere soil beneath three plant species (Vaccinium myrtillus, Juniperus communis and Picea abies) using multiple substrate-induced respiration. We also measured soil physical and chemical properties, plant diversity, climatic factors and morphological and chemical traits of roots in bulk soil (‘community’ level traits, where several plant species were pooled together) and of individual plants (‘species’ level, where roots of single species were excavated). At lower elevations, global catabolic activity in the rhizosphere was higher than in bulk soil, but converged in the nutrient-poor, colder soils found at higher elevations, although changes in catabolic diversity were negligible. Variations in soil texture, cation exchange capacity, carbon and nitrogen content and pH were associated with the global catabolic activity, but these soil properties had minimal effects on catabolic diversity. Climatic variables were related to microbial activity beneath V. myrtillus only and warmer mean annual temperatures increased activity. Plant root traits at the community level in bulk soil had less effect on global catabolic activity than abiotic factors, with thicker roots, high root lignin content and low cellulose content influencing microbial activity, but not altering catabolic diversity. At the species level, more dense root tissue decreased global catabolic activity, reflecting changes in chemical composition. Overall, our results show that soil physical and chemical properties were the main drivers of microbial activity, but that vegetation created distinctive microenvironments that refined these relationships, mainly through modifications in root chemical traits.

Ecological contingency in species shifts: downslope shifts of woody species under warming climate and land-use change

A predicted impact of a warming climate is an upslope shift of montane plant species. These upslope shifts may be amplified by land-use changes or attenuated by forest recoveries at low elevations where historical disturbances were ceased allowing for plant regrowth. Consequently, species may shift downslope back to low elevations where they had been previously harvested. The cessation-driven downslope shifts are hypothesized to dampen or even reverse climate-driven upslope shifts. We tested this hypothesis by a 20 year (1989–2009) forest inventory dataset from five mountainous areas in eastern China. In our study region, intense deforestation occurred mostly at low elevations until 1970, but was then ceased to facilitate natural forest recovery. Based on the analyses of 30 216 woody plants in 609 plots, we found that: (1) forest recovery occurred over the 20 year survey period, and increment rates of both recruitment and basal area increased up to 2004. However, in the last period (2004–2009), increment rates of basal area leveled off and recruitment was close to zero; (2) forest recovery was faster at lower elevations, as indicated by the higher increment rates there; (3) despite rising regional temperatures, the mean elevations of study species showed a downslope shift over the 20 years; and (4) the contribution of forest recovery to elevational shifts was supported by the fact that the species shifts were positively related to elevational changes in the recruitment increment, e.g. the negative (or downslope) shifts occurred in association with higher increments at lower elevations. These results suggest that, the cessation of disturbances and consequent lowland forest recovery had greater effects on the species distributions than did warming climate. In mountain systems that are being allowed to recover from historical disturbances, the effects of forest recovery on species distributions should be explicitly accounted for when assessing and predicting climate change impacts.

Facilitating adaptation to climate change while restoring a montane plant community.

Montane plant communities throughout the world have responded to changes in temperature regimes by shifting ranges upward in elevation, and made downslope movements to track shifts in climatic water balance. Organisms that cannot disperse or adapt biologically to projected climate scenarios in situ may decrease in distributional range and abundance over time. Restoration strategies will need to incorporate the habitat suitability of future predicted conditions to ensure long-term persistence. We propagated seedlings of three native Hawaiian montane plant species from high- (~2,500 m asl) and low-elevation (~1,900 m asl) sources, planted them in 8 common plots along a 500 m elevation gradient, and monitored microclimate at each plot for 20 weeks. We explored how temperature and precipitation influenced survival and growth differently among high- and low-elevation origin seedlings. Significantly more seedlings of only one species, Dodonaea viscosa, from high-elevation origin (75.2%) survived than seedlings from low-elevation origin (58.7%) across the entire elevation gradient. Origin also influenced survival in generalized linear mixed models that controlled for temperature, precipitation, and elevation in D. viscosa and Chenopodium oahuense. Survival increased with elevation and soil moisture for Sophora chrysophylla, while it decreased for the other two species. Responses to microclimate varied between the three montane plant species; there were no common patterns of growth or survival. Although limited in temporal scope, our experiment represents one of the few attempts to examine local adaptation to prospective climate scenarios and addresses challenges to restoration efforts within species’ current ranges.

Plant architecture influences gall abundance in a tropical montane plant species

Sessile and host-specific herbivores, such as gall-inducing insects, are usually patchily distributed within the populations of their host plants, and it has been suggested that both inter- and intra-plant variation affect gall abundance, distribution and survivorship. Variation in plant traits, such as size and architecture, has been previously demonstrated as a determinant of gall distribution. We examined the influence of architectural complexity of the tropical plant Galianthe brasiliensis (Rubiaceae) on the abundance of the stem-galler Lopesia sp. (Diptera, Cecidomyiidae) along an elevation gradient where both insect and plant were distributed. A total of 120 plants were sampled along the gradient and more than 580 galls were counted, while plant architectural complexity was determined by a combination of height and branch ramification. Increased elevation did not influence plant complexity nor gall abundance (both P>0.05), but plant architectural complexity explained more than 60% of the variation in gall abundance along the gradient (R2=0.62, P<0.001). We suggest that the greater availability of meristematic tissues in more architecturally complex plants explains the results found, as this is a key resource for gall occurrence and establishment.

Range contraction to a higher elevation: the likely future of the montane vegetation in South Africa and Lesotho

Global climate change is a major challenge for the future with serious potential impacts on biodiversity. Biodiversity in mountains is particularly vulnerable as many montane species are adapted to narrow microhabitats, making them less able to adjust to a climatic change. It is considered important to investigate range changes in the South African Great Escarpment because of the high levels of biodiversity in these mountains, as well as their importance for water provision in South Africa. The current and future ranges of 46 montane plant species in South Africa and Lesotho were therefore modelled using biomod in R, using presence points and predictor variables which included rainfall and temperature worldclim layers. The performance of distribution models produced was evaluated using the Area Under the receiver operating Curve (AUC), True Skill Statistic (TSS), Sensitivity and Specificity. We calculated beta diversity and species richness changes between current and future climates for the group of 46 species, as well as shifts of the predicted presence region boundaries and centroids. We also analysed shifts in minimum, median and maximum elevations. Results show a contraction in species’ ranges towards higher elevation as has been documented from other mountain regions around the world. These results are a cause for concern as a warming climate is decreasing the potential regions of occurrence of montane species in South Africa and Lesotho’s mountainous regions of high biodiversity. This region is under a diverse range of conservation and land use management practises, and our results suggest a coordinated response to climate change is needed.

Intraspecific variation in traits reduces ability of trait‐based models to predict community structure

AbstractQuestionsIs it possible to predict the composition of local plant assemblages? Trait‐based approaches have offered some promise, especially in cases where deterministic processes such as environmental filtering and niche differentiation shape communities. In this study, we asked how much intraspecific variation contributes to trait distributions within and among plant communities, and whether trait distributions resulting from environmental filtering and niche differentiation can predict accurately the relative species abundances of montane plant species in local communities.LocationWest Elk Mountains, Colorado, USA.MethodsWe collected functional trait, species composition and environmental data from 14 sites along a broad climate gradient in Colorado, USA, ranging in elevation from 2480 to 3560 m. We partitioned the variation within and among sites into intraspecific and interspecific components, and compared the results to values from a recent global meta‐analysis, which examined intraspecific trait variability patterns. We also used these data to parameterize statistical models that have been shown to reproduce patterns associated with the processes of environmental filtering and niche differentiation. We fit two models to the data, one assuming that niche differentiation is invariant among sites, and another assuming that niche differentiation varies among sites.ResultsWe found that the trait‐based models were worse at predicting species relative abundances in local communities than a null model assuming equal abundances of all species. One plausible explanation for the poor performance of the models is that intraspecific variation in functional traits, which in our system was higher than the global averages documented in the meta‐analysis, swamped the effects of interspecific variation in functional traits along the climatic gradient. In particular, almost all variation in root traits was within rather than among species, even among sites.ConclusionOur results suggest that a greater focus be placed on measuring intraspecific trait variability and determining its consequences for community assembly and ecosystem properties.

Long-term shifts in the phenology of rare and endemic Rocky Mountain plants.

• Mountainous regions support high plant productivity, diversity, and endemism, yet are highly vulnerable to climate change. Historical records and model predictions show increasing temperatures across high elevation regions including the Southern Rocky Mountains, which can have a strong influence on the performance and distribution of montane plant species. Rare plant species can be particularly vulnerable to climate change because of their limited abundance and distribution.• We tracked the phenology of rare and endemic species, which are identified as imperiled, across three different habitat types with herbarium records to determine if flowering time has changed over the last century, and if phenological change was related to shifts in climate.• We found that the flowering date of rare species has accelerated 3.1 d every decade (42 d total) since the late 1800s, with plants in sagebrush interbasins showing the strongest accelerations in phenology. High winter temperatures were associated with the acceleration of phenology in low elevation sagebrush and barren river habitats, whereas high spring temperatures explained accelerated phenology in the high elevation alpine habitat. In contrast, high spring temperatures delayed the phenology of plant species in the two low-elevation habitats and precipitation had mixed effects depending on the season.• These results provide evidence for large shifts in the phenology of rare Rocky Mountain plants related to climate, which can have strong effects on plant fitness, the abundance of associated wildlife, and the future of plant conservation in mountainous regions.

Phylogenetic turnover patterns consistent with niche conservatism in montane plant species

Summary A fundamental aim in community ecology is to elucidate the processes structuring communities. The key to understanding community patterns is to account for species differences and similarities in how they respond to large‐scale environmental gradients and partition local resources. Using phylogenetic relationships as a representation of species’ ecological differences, we use phylogenetic beta‐diversity (PBD) to examine how patterns of community relatedness change across space. Specifically, we examine how PBD informs our understanding of the processes (spatial or environmental) directing species assembly along montane environmental gradients – in particular, whether patterns are consistent with niche conservatism. Also, we examine the depth of phylogenetic turnover to see where in evolutionary history shared environmental tolerances appear conserved. For angiosperm communities situated to the east and west of the Continental Divide (CD) in the Rocky Mountain National Park in CO, USA, we compare nine beta‐diversity indices (taxonomic, TBD: Jaccard, Bray–Curtis and Gower; PBD: PhyloSor, UniFrac, Dnn, Dpw, Rao's D and Rao's H) to changes in space, environment and environment controlling for space with the partial PROTEST method. We find that PBD differs from taxonomic beta‐diversity and some PBD metrics were redundant with one another (i.e. Rao's D &amp; Dpw and UniFrac &amp; PhyloSor). The indices’ different sensitivities to evolutionary depth affected their responses to environmental and spatial gradients: TBD consistently associated greater with all factors (space, environment and environment controlled for space) than PBD metrics; PBD metrics more sensitive to recent changes were more highly correlated with all factors than those metrics sensitive to turnover deeper in the phylogeny. Generally, beta‐diversity associated strongest with environment and least with space. Synthesis. Taxonomic and phylogenetic beta‐diversity complements each other to provide an enhanced perspective of the process governing community structure. Together, they depict patterns expected under niche conservatism for the Rocky Mountain angiosperm communities, that is, species’ names change faster than their evolutionary relationships across space.

Projected range contractions of European protected oceanic montane plant communities: focus on climate change impacts is essential for their future conservation.

Global climate is rapidly changing and while many studies have investigated the potential impacts of this on the distribution of montane plant species and communities, few have focused on those with oceanic montane affinities. In Europe, highly sensitive bryophyte species reach their optimum occurrence, highest diversity and abundance in the north-west hyperoceanic regions, while a number of montane vascular plant species occur here at the edge of their range. This study evaluates the potential impact of climate change on the distribution of these species and assesses the implications for EU Habitats Directive-protected oceanic montane plant communities. We applied an ensemble of species distribution modelling techniques, using atlas data of 30 vascular plant and bryophyte species, to calculate range changes under projected future climate change. The future effectiveness of the protected area network to conserve these species was evaluated using gap analysis. We found that the majority of these montane species are projected to lose suitable climate space, primarily at lower altitudes, or that areas of suitable climate will principally shift northwards. In particular, rare oceanic montane bryophytes have poor dispersal capacity and are likely to be especially vulnerable to contractions in their current climate space. Significantly different projected range change responses were found between 1) oceanic montane bryophytes and vascular plants; 2) species belonging to different montane plant communities; 3) species categorised according to different biomes and eastern limit classifications. The inclusion of topographical variables in addition to climate, significantly improved the statistical and spatial performance of models. The current protected area network is projected to become less effective, especially for specialised arctic-montane species, posing a challenge to conserving oceanic montane plant communities. Conservation management plans need significantly greater focus on potential climate change impacts, including models with higher-resolution species distribution and environmental data, to aid these communities' long-term survival.

Geographic distance is more relevant than elevation to patterns of outbreeding in Ranunculus bulbosus

Summary Mountain ecosystems can exert different selection pressures on plant populations over small scales due to steep environmental gradients. Gene flow between lower‐ and higher‐elevation plant populations could lead to the increased integration of potentially adaptive genes and thereby to outbreeding vigour under current rapid climatic changes. Alternatively, gene flow across elevation could disrupt gene complexes leading to outbreeding depression. We explored the responses of higher (1800 m a.s.l.) and lower (1200 m a.s.l.) Ranunculus bulbosusL. populations to intra‐ and interelevational and short‐ as well as long‐distance gene flow by means of controlled crosses and assessment of the offspring's germination, growth and fitness. Outbreeding differed between elevations of origin: higher populations were negatively affected by pollen flow from lower populations at the earliest life stages, but tended to be positively affected in terms of growth later on while gene flow across small vs. large distances had no impact on growth traits. Lower populations were not significantly affected by the elevational origin of pollen per se. However, fitness of offspring of populations from both higher and lower elevations was jointly affected by elevational and regional origins of pollen, in which case the gene flow distance had a comparatively stronger positive impact on fitness (outbreeding vigour) than elevational origin. Synthesis: Our results indicate that compared to gene flow at regional scales, gene flow across elevational gradients has a minor effect on R. bulbosus. The lack of outbreeding depression suggests that potentially adaptive genes might well be integrated across populations resulting in an increased resilience of R. bulbosus and potentially similar montane plant species in changing climatic conditions.

Dramatic response to climate change in the Southwest: Robert Whittaker's 1963 Arizona Mountain plant transect revisited

Models analyzing how Southwestern plant communities will respond to climate change predict that increases in temperature will lead to upward elevational shifts of montane species. We tested this hypothesis by reexamining Robert Whittaker's 1963 plant transect in the Santa Catalina Mountains of southern Arizona, finding that this process is already well underway. Our survey, five decades after Whittaker's, reveals large changes in the elevational ranges of common montane plants, while mean annual rainfall has decreased over the past 20 years, and mean annual temperatures increased 0.25°C/decade from 1949 to 2011 in the Tucson Basin. Although elevational changes in species are individualistic, significant overall upward movement of the lower elevation boundaries, and elevational range contractions, have occurred. This is the first documentation of significant upward shifts of lower elevation range boundaries in Southwestern montane plant species over decadal time, confirming that previous hypotheses are correct in their prediction that mountain communities in the Southwest will be strongly impacted by warming, and that the Southwest is already experiencing a rapid vegetation change.

Forest patches and the upward migration of timberline in the southern Peruvian Andes

Montane plant species around the globe are predicted to shift their distributions upslope in response to increasing temperatures associated with climate change. In the tropical Andes, which are one of the most diverse and threatened of all biodiversity hotspots, many plant and animal species have already started to shift their distributions to higher elevations in response to warming. However, a variety of biotic and abiotic factors may stabilize Andean timberlines and halt further upslope migrations into the high elevation grasslands (referred to as “puna” in southern Peru) above the forest. One possibility is that small forest patches that occur above-timberline throughout the Andes may facilitate forest expansion into newly suitable areas in the puna, yet little is known about the ecology or function of these patches. In this study, we examined seedling recruitment patterns, seed dispersal, and microclimate at the timberline, in and around above-timberline forest patches, and in the puna. The above-timberline forest patches had similar patterns of seed dispersal as the timberline but overal <1% of captured seeds were dispersed 10m into the puna. At both the patch edges and the forest timberline, seedling abundances were lower in the puna relative to the adjacent forest and forest–puna ecotone. This reduction may be a result of reduced seed dispersal across the forest–puna ecotone and/or decreased germination of dispersed seeds due to the harsh microclimatic conditions occurring in the puna (daily temperature fluctuations are greatly elevated in the puna relative to the forest and frost events are more frequent and severe). While increasing temperatures associated with climate change may ameliorate some of the severe climatic conditions occurring in the puna, it will not directly affect other potential recruitment limitations such as reduced seed dispersal, high levels of UV radiation, and anthropogenic activities (cattle grazing and fires) in the puna. With the reduction of anthropogenic activities, above-timberline forest patches may serve as nucleating foci for future forest expansion into the puna. However, our results indicate that any upslope migration of the timberline into the puna will likely occur at a rate that is slower than what is required to keep pace with warming because recruitment is restricted to a narrow strip along the forest–puna borders. Slowed forest expansion into the puna could act as a barrier to the upslope migration of Andean cloud forest species leading to extreme losses of Andean biodiversity.

Ice-age isolation, postglacial hybridization and recent population bottlenecks shape the genetic structure of Meum athamanticum in Central Europe

Phylogeographic analyses can help to reveal the refugial structure of plants during and after the ice ages, but the detailed history of regional refugial isolation and differentiation in Central Europe is still poorly understood. A recent study of Meum athamanticum in its total range of occurrences revealed persistence of this temperate montane plant species in Central Europe north of the Alps, without going into details. We therefore aimed to study differentiation and migration processes of this plant species in more detail throughout Central Europe. We used high resolution amplified fragment length polymorphisms (AFLP) markers and analyzed 210 plant individuals of 14 Central European populations with three pairs of primer combinations (128 loci, 111 of which polymorphic). The data show genetic differentiation and varying levels of molecular diversity within populations and groups of populations. Altogether, the studied populations did not show a gradient in molecular variation along presumptive postglacial migration routes across Central Europe. Rather, they reveal a genetic division into seven major groups. Four of them are characterised by high genetic diversity, private fragments and higher than average number of rare and sparse fragments, leading to the assumption that they are descendants of independent populations which survived in glacial refugia. In combination with information from paleoclimate and paleovegetation, it is likely that microclimatically favoured habitats at (i) the eastern flank of the Black Forest, (ii) the southern margin of the Cologne basin, (iii) the foothills of the Erzgebirge, and (iv) the foothills of the Jura Mountains acted as sources for the postglacial recolonisation of this species to the other mountains of Central Europe. As some of the populations analysed show intermixed gene-pools (i.e. including genetic information from different groups) and partly have exceptionally high genetic diversity, but no private and only relatively few rare or sparse fragments, they might represent contact zones. On the other hand, genetic pauperization and isolation of two other populations in connection with extremely small population sizes and unfavourable habitat conditions seem to reflect recent bottlenecks. Consequently, the genetic structure of M. athamanticum in Central Europe is shaped by (i) extra-Mediterranean glacial refugia in situ, (ii) following postglacial hybridization along emerging contact zones and (iii) genetic bottlenecks in thereafter isolated small populations. All results provide evidences for small scale migration of the species between Central European valleys and surrounding highlands. Therefore, our study provides molecular evidence for both climate dependent wide ranging periglacial tabula rasa, but some small refugia in locally buffered areas. We hereby show that the environmental heterogeneity of cold stage landscapes in Central Europe is generally underestimated.

The response of flowering time to global warming in a high-altitude plant: the impact of genetics and the environment

In high-altitude habitats, an increase in temperature and greater precipitation in the form of rain represent climate changes typically associated with global warming. We determined whether phenotypic plasticity and genetic changes in the mean phenotype could affect the adaptation of flowering time to changes in the environment resulting from global warming in a montane plant species, Aquilegia coerulea James. We collected seeds from 17 plants from each of three natural populations. For each of these 51 families, we assigned 3–4 individuals to each of four water and temperature treatments. We observed phenotypic plasticity in flowering time in response to both temperature and water availability but no genetic variance or genetic differentiation in phenotypic plasticity. These results indicate that phenotypic plasticity could provide a quick response to environmental changes but provides little evolutionary potential. In contrast to phenotypic plasticity in flowering time, the mean flowering time did vary among families and among populations, suggesting a genetic basis to flowering time and adaptation in the different populations. The most likely scenario for the adaptation of this plant species to climate change is a rapid response via phenotypic plasticity followed by selection and micro-evolutionary changes in the mean phenotype.

A horvátországi Drávaköz bükkállományai (Circaeo-Carpinetum Borhidi 2003 em. Kevey 2006b fagetosum Raus 1975)

This paper presents the coenological analysis of a few lowland beech forest stands. The studied area is located in the north-eastern part of Croatia, in the Baranja region (Titelicum floral subdistrict). Several montane plant species are found int he investigated stands, probably originating from the "Beech I. " period (from 3000 B.C. to 800 B.C.), whereas several submediterranean species probably have survived from the "Oak period" (from 5500 B.C. to 3000 B.C.). Based on former research results, these lowland beech stands can be considered a beech subassociation of oak-hornbeam forests of the plains {Circaeo-Carpinetum fagetosum). The presence of some submediterranean plants call the attention to the relatedness of these stands to oak-hornbeam forests (Asperulo taurinae-Carpinetum) and beechwoods {Helleboro odoro-Fagetum) of the neighbouring Mecsek floral subdistrict (Sopianicum). These beech stands are of high significance in terms of floristic and vegetation history, thus deserve strict protection.

Genetic diversity across natural populations of three montane plant species from the Western Ghats, India revealed by intersimple sequence repeats.

We analysed genetic diversity across the natural populations of three montane plant species in the Western Ghats, India; Symplocos laurina, Gaultheria fragrantissima and Eurya nitida using intersimple sequence repeat (ISSR) markers. These markers revealed genetic diversity within the populations of these plants from Nilgiri and also between two populations of S. laurina from Nilgiri and Amboli. Genetic variation within and between populations was analysed using various parameters such as total heterozygosity (HT), heterozygosity within population (HS), diversity between populations (DST), coefficient of population differentiation (GST), genetic distance (D) and gene flow (Nm). Total heterozygosity (HT) was higher for S. laurina (0.238) than for G. fragrantissima (0.172) and E. nitida (0.182). Two populations of S. laurina, separated by > 1000 km, showed a high within-population variation (53.7%) and a low gene flow (Nm = 0.447). upgma phenograms depicted a tendency of accessions to group according to their geographical locations in all the three plant species. The insight gained into the genetic structure of these plant populations might have implications in developing in situ and ex situ conservation strategies.