Low Alpine Research Articles

Concentration of Nutrients in Individual Organs of European Beech (Fagus sylvatica L.) Seedlings and Root System Development as a Result of Different Fertilization

The large-scale dieback of spruce monocultures, especially in the lower alpine, has become a significant problem and has necessitated the restoration of these areas, mainly using seedlings produced in forest nurseries. The primary source of nutrients for seedlings can be slow-release fertilizers and an appropriate dose of fertilizer improves the efficiency of its use and minimizes the negative environmental impact associated with the excessive use of mineral fertilizers. Aims: This study aimed to evaluate the effect of applying different fertilizer dose combinations on the accumulation of macronutrients in different parts of the seedlings (roots, shoots, and leaves) and on the morphology and development of fine roots. Methods: This research was carried out on producing beech seedlings with the application of starter soil fertilization with Yara Mila Complex (YMC) and Osmocote Exact Standard 3-4M (OES) fertilizers in four varying doses. Results: No deficiency of the analyzed macronutrients was noted in any of the tested fertilization variants. The highest content of all analyzed macronutrients was recorded in the leaves of beech seedlings, with values in roots and shoots being several times lower. The mixed fertilization variant OES 1.0 + YMC 1.0 shows a positive correlation with all analyzed elements and the parameters DQI (Dickson Quality Index), SA (Surface Area), RV (Root Volume), and mass. Conclusions: Results confirm the hypothesis that applying a mixture of fast-acting (YMC) and slow-acting (OES) fertilizer positively affects the nutrition and accumulation of macronutrients and the development of root systems in beech seedlings compared to fertilization with a single fertilizer.

The highest-altitude recorded find of the adder <i>Vipera berus</i> (Linnaeus, 1758) in Slovenia on Mt Mali Kanin (Western Julian Alps)

The article describes the find of a single individual of the adder (Vipera berus) on Mt Mali Kanin (Western Julian Alps, Slovenian-Italian border) at 2,570 m a.s.l. on 8.7.2023. The animal with a total length of about 40 cm was photographed on a patch of soil and low alpine vegetation in a predominantly rocky habitat. According to the available published and unpublished data, this find is 325 m higher than the previous highest-altitude recorded find of the species in Slovenia.

Cuphophyllus monteverdae and C. hygrocyboides (Hygrophoraceae, Agaricales) in Norway and Sweden

Two poorly known and relatively rare waxcaps Hygrocybe monteverdae and Cuphophyllus hygrocyboides are described, withnotes regarding their distribution and ecological preferences in Norway and Sweden. H. monteverdae is a whitish species originally described from the Canary Islands, characterized by the darkening lamella upon drying. It resembles a slender C. pratensis inhabitus but is whitish. C. hygrocyboides also resembles C. pratensis in both colour and habitus but can be separated based on morphology. C. hygrocyboides is found in calcareous semi-natural grasslands, especially pastures, and also in the low alpine zone and higher alpine vegetation. It is not found below the mid-boreal zone even if it has been found at sea level in the northern part of Norway. H. monteverdae seems to be a strict lowland species found in semi-natural grasslands, alvar vegetation, and open grazed forests on calcareous ground. Phylogenetic analysis shows that H. monteverdae belongs in Cuphophyllus, and the new combination to Cuphophyllus is here proposed.

The Inocybe-Conocybe workshops at Dombås 2021-2022

Some results from the Inocybe(-Conocybe) workshops at Dombås 2021-2022 are presented, with emphasis on the 2021 Inocyberesults, based on extensive ITS-DNA sequencing and phylogenetic analyses. Among the 60 Inocybe s. lat. species sequence-verified in 2021, 30 were new to Norway. Most species were found in subalpine tall-herb Betula forests and calcareous low alpine Betulanana-Salix thickets, and more than half of the species are believed to be preferentially alpine-subalpine taxa.

When sunlight goes out, avoidance mechanisms are defective for protecting flowers from freezing damage

In high mountain species, flowers are considered the most frost-sensitive organs of plants. Such frost sensibility relates to the fact that most flowers do not tolerate ice formation in their tissues, suggesting that freezing avoidance mechanisms would be highly selected to protecting these vital organs from freezing damage. Despite this, the function and regulation of avoidance mechanisms in flowers have been poorly studied. This study assessed the importance of freezing avoidance mechanisms in alpine species from the central Chilean Andes. Reproductive shoots of 14 herbaceous species from the subalpine and low alpine belts in the central Chilean Andes were collected during peak flowering in the field and transported to the lab to study ice formation and propagation. The frequency and effectiveness of structural ice barriers (SIB) and the effect of inflorescence morphology on thermal decoupling were quantified by infrared thermography. SIBs were detected in 9 out of the 14 studied species but were effective only in three. Moreover, no thermal decoupling was detected in any studied species, independent of their inflorescence type. We conclude that SIBs and inflorescence morphology are insufficient to protect flowers from damage caused by night freezing events.

Elevated natural radioactivity in undisturbed forest and mountain areas of arctic Norway – local geology, soil characteristics, and transfer to biota

This study deals with the geology in areas close to a large unexploited uranium deposit and the impact of bedrock characteristics on levels of radionuclides and other elements in soil and biota. Factors influencing soil inventory and ecosystem transfer are discussed, focussing on 238U, 226Ra, and 210Pb. Field work was carried out in Salangen Valley in Northern Norway. Sampling stations for soil and biota covered different habitats – grassland, birch forest and low alpine heathland. The geological survey confirmed uranium-bearing minerals in granitic gneiss and pegmatites. There was large variation in the local occurrence of uranium, reflecting the irregular nature of the pegmatite. Activity concentrations of 238U, 226Ra, and 210Pb in surface soil were elevated at sites close to U-enhanced bedrock, compared to sites with other types of bedrock. Particularly high soil levels were found for 226Ra and 210Pb, whereas activity concentrations of 238U were more variable, depending of local soil characteristics. Levels of other natural radionuclides (40K, 232Th) merely increased with soil mineral content, and concentrations of heavy metals were generally low at all sites. External dose rate (1 m above ground surface) was closely correlated with 226Ra levels in soil. Plant levels of 238U and 226Ra varied by several orders of magnitude depending on soil level and plant species, whereas plant levels of 210Pb and 210Po were largely affected by aerial fallout. Berries generally contained lower levels of 238U and 226Ra than green plant parts. As was the case for plants, the levels of 238U in earthworms were strongly correlated with the respective concentrations in the soil. Soil-to-plant transfer was markedly higher for 226Ra than for 238U. For both radionuclides, a positive correlation was found between concentration ratios of V. myrtillus (heath) and soil organic matter content. The 238U concentration ratios for earthworms were generally two orders of magnitude higher than for plants.

Plant density and life history traits of Aconitum spicatum in North-central Nepal: effects of elevation and anthropogenic disturbances.

Increasing cross-border trade of medicinal and aromatic plants (MAPs) has put heavy pressure on a considerable number of species in the Himalayas. One of the threatened species in Nepal is Aconitum spicatum. Unfortunately for this species and for many others, our knowledge on population ecology and performance across the distribution range is insufficient, hindering the formulation of species-specific management plans. We therefore studied density and population structure of A. spicatum and assessed variation in its life history traits among three populations (subalpine, lower alpine and alpine) along an elevation gradient (3,000–4,200 m a.s.l.) in Annapurna Conservation Area, north-central Nepal. The results show that human disturbances and topographic factors contributed to the variation in density and life history traits. The overall density ranged between 0.56 ± 0.09 (Mean ± SE) and 2.48 ± 0.24 plants/m2 with highest mean density in the lower alpine and lowest in the subalpine population. The subalpine population was also characterized by lower investment in reproductive structures with lowest seed mass and low seed viability and fecundity. Among the environmental variables tested, harvesting, animal droppings and fire appeared to be the most important factors affecting density of different life stages of A. spicatum. The prevailing harvesting pattern is destructive as it involves uprooting of the whole plant and this appears to be a main reason for low recruitment and reduced density of the subalpine population. The level of disturbance decreased with increasing elevation. In terms of reproductive effort, the alpine population performed best. Our results indicate that the viability of A. spicatum populations depends on controlling over-harvesting and pre-mature harvesting of tubers and protecting younger life stages from grazing, trampling and fire. We therefore recommend that when formulating management guidelines, measures aiming to mitigate such anthropogenic disturbances should be considered.

The Role of Low Soil Temperature for Photosynthesis and Stomatal Conductance of Three Graminoids From Different Elevations.

In high-elevation grasslands, plants can encounter periods with high air temperature while the soil remains cold, which may lead to a temporary mismatch in the physiological activity of leaves and roots. In a climate chamber experiment with graminoid species from three elevations (4400, 2400, and 250 m a.s.l.), we tested the hypothesis that soil temperature can influence photosynthesis and stomatal conductance independently of air temperature. Soil monoliths with swards of Kobresia pygmaea (high alpine), Nardus stricta (lower alpine), and Deschampsia flexuosa (upper lowland) were exposed to soil temperatures of 25, 15, 5, and -2°C and air temperatures of 20 and 10°C for examining the effect of independent soil and air temperature variation on photosynthesis, leaf dark respiration, and stomatal conductance and transpiration. Soil frost (-2°C) had a strong negative effect on gas exchange and stomatal conductance in all three species, independent of the elevation of origin. Leaf dark respiration was stimulated by soil frost in D. flexuosa, but not in K. pygmaea, which also had a lower temperature optimum of photosynthesis. Soil cooling from 15 to 5°C did not significantly reduce stomatal conductance and gas exchange in any of the species. We conclude that all three graminoids are able to maintain a relatively high root water uptake in cold, non-frozen soil, but the high-alpine K. pygmaea seems to be especially well adapted to warm shoot – cold root episodes, as it has a higher photosynthetic activity at 10 than 20°C air temperature and does not up-regulate leaf dark respiration upon soil freezing, as was observed in the grasses from warmer climates.

Belowground plant parts are crucial for comprehensively estimating total plant richness in herbaceous and woody habitats.

Most studies consider aboveground plant species richness as a representative biodiversity measure. This approach inevitably assumes that the partitioning of total plant species richness into above- and belowground components is constant or at least consistent within and across vegetation types. However, with studies considering belowground plant richness still scarce and completely absent along vegetation gradients, this assumption lacks experimental support. Novel DNA sequencing techniques allow economical, high-throughput species identification of belowground environmental samples, enabling the measurement of the contributions of both above- and belowground plant components to total plant richness. We investigated above- and belowground plant species richness in four vegetation types (birch forest, heath, low alpine tundra, high alpine tundra) at the scale of herbaceous plant neighborhoods (dm) using 454 sequencing of the chloroplast trnL (UAA) intron to determine the plant species richness of environmental root samples and combined it with aboveground data from vegetation surveys to obtain total plant species richness. We correlated the measured plant species richness components with each other and with their respective plant biomass components within and across vegetation types. Total plant species richness exceeded aboveground richness twice on average and by as much as three times in low alpine tundra, indicating that a significant fraction of belowground plant richness cannot be recorded aboveground. More importantly, no consistent relationship among richness components (above- and belowground) was found within or across vegetation types, indicating that aboveground richness alone cannot predict total plant richness in contrasting vegetation types. Finally, no consistent relationship between plant richness and the corresponding biomass component was found. Our results clearly show that aboveground plant richness alone is a poor estimator of total plant species richness within and across different vegetation types. Consequently, it is crucial to account for belowground plant richness in future plant ecological studies in order to validate currently accepted plant richness patterns, as well as to measure potential changes in plant community composition in a changing environment.

Trigger characteristics of torrential flows from high to low alpine regions in Austria

Torrential processes like fluvial flows (flash floods with or without intensive sediment transport) and debris flows can represent a threat to people and infrastructure in alpine domains. Up to now the hydro-meteorological trigger conditions and their connection with geomorphic watershed characteristics that favor the initiation of either process are largely unknown. Based on modeled wetness states we determined the trigger types (long-lasting rainfall (LLR), short-duration storm (SDS) and intense snow melt (SM)) of 360 observed debris flow and fluvial flood events in six climatically and geomorphologically contrasting watersheds in Austria. Results show that the watershed wetness states play very distinct roles for triggering torrential events across the study regions. Hydro-meteorological variables have little power to explain the occurrence of fluvial flows and debris flows in these regions. Nevertheless, trigger type separation highlighted some geomorphic influences. For example, intense SM triggered more events in sub-watersheds (torrential watersheds in the study region) that are characterized by significantly higher Melton ruggedness numbers than LLR does. In addition, the data show that events triggered by LLRs occur in sub-watersheds of similar exposures (aspects) other than SDS. The results suggest that the consideration of different trigger types provides valuable information for engineering risk assessment.

Ecosystem services as an integrative framework: What is the potential?

Ecosystems approaches, and among them the ecosystem services (ES) framework, are held as promising vehicles for holistic thinking which is usually taken to mean integration of society and nature. The notion of ES is also seen to aid us in saying something about how and what people value in nature. It is hence surprising that among a huge number of scientific works couched in terms in ES, still relatively few explore the explicit engagement of such concepts with stakeholders with respect to empirical issues, including integration. Motivated by a need to empirically test rather than assume the integrative work of ES, we ask: what ways of using the framework as a stakeholder tool are invited, and does integration unfold in practice? Our evidence comes from a study of a group of stakeholders’ perspectives on sustainable management of sheep grazing in low alpine landscapes in the south of Norway. According to the stakeholders, grazing intensity, type and spatiality cannot be understood and arrived at without accounting for how grazing pressure is the result of the co-production of nature and society. By way of four empirical examples, we demonstrate 1) the integrative agency ES can have, 2) how ES can work to integrate despite the framework, 3) how ES can work against integration, and 4) the implicit agency of ES for the co-production of sustainability and grazing pressures. The study demonstrates that there are particular weaknesses in the concept as an integrative device regarding the invisibility of human co-agency. Furthermore, the precise methodological framing of the research is found to be crucial for whether and how human co-agency is made visible through the framework, and thus how ES works as an integrative framework.

Phenotypic plasticity and water availability: responses of alpine herb species along an elevation gradient

BackgroundAlpine regions are particularly vulnerable to the effects of climate change. The Australian Alps are potentially more so than other mountain regions, as they cover a very small geographic area (<0.05% of mainland Australia), with a low maximum elevation (2228 m). Therefore, response to climate change will be primarily determined by the ability of species to survive in-situ through local adaptation or phenotypic plasticity. Existing climate change models project not only warming but increasingly variable precipitation and snow cover across the Australian Alps. Thus, plasticity in water use traits may become increasingly important for the establishment and persistence of Australian alpine plants. Given that plants from lower elevations inhabit a more heterogeneous environment with more frequent frosts, greater temperature extremes, and higher evapotranspiration, we predict plasticity – and particularly adaptive plasticity – may be more common at low relative to high elevation. To test these predictions we investigated the extent of plasticity and the adaptive value thereof in water use traits in three herbaceous Australian alpine plant species. Seeds were collected from low and high elevation alpine sites and grown at ample and limiting water availability under common-garden conditions. For morphological and physiological traits, we compared both their means and phenotypic plasticity across treatments and elevations.ResultsResponses of morphological and physiological traits to water availability were in accord with many previous studies of water response. Although previous work in the same environment demonstrated greater plasticity in response to temperature for low elevation populations, plasticity in response to water availability in our study showed markedly little variation as a function of elevation. Rather, patterns of plasticity were highly variable among species and among traits within species, with few instances of adaptive plastic responses.ConclusionWe discuss the difficulties in observing adaptive plasticity and the importance of microhabitat variation in shaping the persistence of these Australian alpine species.

Impact of climate change on alpine vegetation of mountain summits in Norway

Climate change is affecting the composition and functioning of ecosystems across the globe. Mountain ecosystems are particularly sensitive to climate warming since their biota is generally limited by low temperatures. Cryptogams such as lichens and bryophytes are important for the biodiversity and functioning of these ecosystems, but have not often been incorporated in vegetation resurvey studies. Hence, we lack a good understanding of how vascular plants, lichens and bryophytes respond interactively to climate warming in alpine communities. Here we quantified long-term changes in species richness, cover, composition and thermophilization (i.e. the increasing dominance of warm-adapted species) of vascular plants, lichens and bryophytes on four summits at Dovrefjell, Norway. These summits are situated along an elevational gradient from the low alpine to high alpine zone and were surveyed for all species in 2001, 2008 and 2015. During the 15-year period, a decline in lichen richness and increase in bryophyte richness was detected, whereas no change in vascular plant richness was found. Dwarf-shrub abundance progressively increased at the expense of lichens, and thermophilization was most pronounced for vascular plants, but occurred only on the lowest summits and northern aspects. Lichens showed less thermophilization and, for the bryophytes, no significant thermophilization was found. Although recent climate change may have primarily caused the observed changes in vegetation, combined effects with non-climatic factors (e.g. grazing and trampling) are likely important as well. At a larger scale, alpine vegetation shifts could have a profound impact on biosphere functioning with feedbacks to the global climate.

Infiltration under snow cover: Modeling approaches and predictive uncertainty

Groundwater recharge from snowmelt represents a temporal redistribution of precipitation. This is extremely important because the rate and timing of snowpack drainage has substantial consequences to aquifer recharge patterns, which in turn affect groundwater availability throughout the rest of the year. The modeling methods developed to estimate drainage from a snowpack, which typically rely on temporally-dense point-measurements or temporally-limited spatially-dispersed calibration data, range in complexity from the simple degree-day method to more complex and physically-based energy balance approaches. While the gamut of snowmelt models are routinely used to aid in water resource management, a comparison of snowmelt models’ predictive uncertainties had previously not been done. Therefore, we established a snowmelt model calibration dataset that is both temporally dense and represents the integrated snowmelt infiltration signal for the Vers Chez le Brandt research catchment, which functions as a rather unique natural lysimeter. We then evaluated the uncertainty associated with the degree-day, a modified degree-day and energy balance snowmelt model predictions using the null-space Monte Carlo approach. All three melt models underestimate total snowpack drainage, underestimate the rate of early and midwinter drainage and overestimate spring snowmelt rates. The actual rate of snowpack water loss is more constant over the course of the entire winter season than the snowmelt models would imply, indicating that mid-winter melt can contribute as significantly as springtime snowmelt to groundwater recharge in low alpine settings. Further, actual groundwater recharge could be between 2 and 31% greater than snowmelt models suggest, over the total winter season. This study shows that snowmelt model predictions can have considerable uncertainty, which may be reduced by the inclusion of more data that allows for the use of more complex approaches such as the energy balance method. Further, our study demonstrated that an uncertainty analysis of model predictions is easily accomplished due to the low computational demand of the models and efficient calibration software and is absolutely worth the additional investment. Lastly, development of a systematic instrumentation that evaluates the distributed, temporal evolution of snowpack drainage is vital for optimal understanding and management of cold-climate hydrologic systems.

Assessing adaptability and response of vegetation to glacier recession in the afro-alpine moorland terrestrial ecosystem of Rwenzori Mountains

The objective of this study was to explore vegetation adaptability in a changing afro-alpine moorland terrestrial ecosystem on Mt. Rwenzori and to determine whether there were any links with response of vegetation to glacier recession. We analyzed the composition and distribution of plant species in relation to soils, geomorphic processes, and landscape positions in the Alpine zone. To accomplish this objective, archival data sources and published reports for this ecosystem were reviewed. A field trip was conducted in 2010 to study in detail seven vegetation sampling plots that were systematically selected using GIS maps and a nested-quadrat sampling design framework along an altitudinal gradient in the lower and upper alpine zones. Using these sampling plots, 105 vegetation and 13 soil samples were assessed in the alpine zone. Soil samples were taken for laboratory testing and analysis. The results show statistically significant differences in pH, OM, N, P, Ca, Mg, and K pools between soils samples drawn from the lower and upper alpine sites (p < 0.0033). Furthermore, we observed a significant vegetation formation with numerous structural forms, but there was a limited diversity of species. The most significant forms included Alchemilla carpets, Bogs, Dendrosenecio woodland, and Scree slopes. The lower alpine area (3500–3900 masl) had a more diverse plant species than other areas, especially Alchemilla argyrophylla and Dendrosenecio adnivalis species that were evident due to well-drained deeper soils. The Alchemilla subnivalis were evident at a higher altitude of above 4000 masl. Shifts in the Astareceae (e.g. Senecio species) were particularly prominent even on recently deglaciated areas. The spatial variations of species distribution, structure, and composition suggest there are serious implications in terms of ecosystem adaptability, resilience, and stability that require further evaluation.

Poa densa(Poaceae), an overlooked Turkish steppe grass, and the evolution of bulbs inPoa

Abstract: Poa densa Troitsky is a characteristic species of the high steppe to low alpine vegetation of Turkey. It was overlooked in the Flora of Turkey, and although subsequently reported from a few stations in W part of C Anatolia, is actually relatively common and widespread across the semi-arid C and N steppes. Here we provide a key to related species, a full description, photographs, 2C value of nuclear DNA content, and a distribution map, and discuss its classification in the genus. The synonym Festuca conferta is lectotypified. DNA phylogenetic analysis and morphology data indicate P. densa is allied to species of P. subg. Poa sect. Macropoa, rather than to the P. bulbosa complex of P. subg. Ochlopoa sect. Arenariae, and support multiple origins of the basal bulb in the genus Poa. Citation: Cabi E., Soreng R. J., Gillespie L. & Amiri N. 2016: Poa densa (Poaceae), an overlooked Turkish steppe grass, and the evolution of bulbs in Poa. — Willdenowia 46: 201–211. doi: http://dx.doi.org/10.3372/wi.46.46...

Climate variability and long-term expansion of peatlands in Arctic Norway during the late Pliocene (ODP Site 642, Norwegian Sea)

Abstract. Little is known about the terrestrial response of high-latitude Scandinavian vegetation to the warmer-than-present climate of the late Pliocene (Piacenzian, 3.60–2.58 Ma). In order to assess Piacenzian terrestrial climate variability, we present the first high-resolution reconstruction of vegetation and climate change in northern Norway between 3.6 and 3.14 Ma. The reconstructions are derived from pollen assemblages in the marine sediments of ODP Hole 642B, Norwegian Sea (67° N). The palynological assemblages provide a unique record of latitudinal and altitudinal shifting of the forest boundaries, with vegetation alternating between cool temperate forest during warmer-than-present intervals and boreal forest similar to today during cooler intervals. The northern boundary of the nemoral to boreonemoral forest zone was displaced at least 4–8° further north, and warmest-month temperatures were 6–14.5 °C higher than at present during warm phases. Warm climatic conditions persisted during the earliest Piacenzian (ca. 3.6–3.47 Ma) with diverse cool temperate nemoral to boreonemoral forests growing in the lowlands of the Scandinavian mountains. A distinct cooling event at ca. 3.47 Ma resulted in a southward shift of vegetation zones, leading to the predominance of boreal forest and the development of open, low alpine environments. The cooling culminated around 3.3 Ma, coinciding with Marine Isotope Stage (MIS) M2. Warmer climate conditions returned after ca. 3.29 Ma, with higher climate variability indicated by the repeated expansion of forests and peatlands during warmer and cooler periods, respectively. Climate progressively cooled after 3.18 Ma, resembling climatic conditions during MIS M2. A high variability of Norwegian vegetation and climate changes during the Piacenzian is superimposed on a long-term cooling trend. This cooling was accompanied by an expansion of Sphagnum peatlands that potentially contributed to the decline in atmospheric CO2 concentrations at the end of the Piacenzian warm period and facilitated ice growth through positive vegetation–snow albedo feedbacks. Correlations with other Northern Hemisphere vegetation records suggest hemisphere-wide effects of climate cooling.

Patterns of reptile and amphibian species richness along elevational gradients in Mt. Kenya.

Faunal species richness is traditionally assumed to decrease with increasing elevation and decreasing primary productivity. Species richness is reported to peak at mid-elevation. This survey examines the herpetofaunal diversity and distribution in Mt. Kenya (central Kenya) by testing the hypothesis that changes in species richness with elevation relate to elevation-dependent changes in climate. Sampling along transects from an elevation of approximately 1 700 m in Chogoria forest block (wind-ward side) and approximately 2 600 m in Sirimon block (rain shadow zone) upwards in March 2009. This starts from the forest to montane alpine zones. Sampling of reptiles and amphibians uses pitfall traps associated with drift fences, time-limited searches and visual encounter surveys. The results show that herpetofaunal richness differs among three vegetation zones along the elevation gradient. Chogoria has higher biodiversity than Sirimon. More species occur at low and middle elevations and few exist at high elevations. The trends are consistent with expected optimum water and energy variables. The lower alpine montane zone has high species richness but low diversity due to dominance of some high elevations species. Unambiguous data do not support a mid-domain effect (mid-elevation peak) because the observed trend better fits a model in which climatic variables (rainfall and temperature) control species richness, which indirectly measures productivity. It is important to continue protection of all indigenous forests, especially at low to mid elevations. These areas are vulnerable to human destruction yet are home to some endemic species. Firebreaks can limit the spread of the perennial wildfires, especially on the moorlands.

Variation and response to experimental warming in a New Zealand cushion plant species

AbstractCold adapted plants, such as cushion plants, may be particularly sensitive to climate warming because of their compact growth form and high branch density. In the oceanic southern hemisphere, cushion communities tend to have large range distributions at low latitudes (sea level to low alpine), thus providing an opportunity to test the effects of temperature on plant morphology and reproduction across gradients. Using Donatia novae‐zelandiae as a model species, we compared the leaf morphology, reproduction and responses to warming. Two low‐alpine sites (Maungatua (880 m a.s.l.), Blue Mountains (1000 m a.s.l.)) and two sea‐level sites (Waituna 1 (0 m a.s.l.), Waituna 2 (0 m a.s.l.)) in South Island, New Zealand were used. Donatia novae‐zelandiae cushions differed significantly between the high‐elevation and sea‐level sites both morphologically and in terms of reproduction. High‐elevation cushions produced more flowers (threefold more flowers per plant) and seeds (sevenfold more seeds per capsule) than at sea level, but leaves were larger at sea level (in length and specific leaf area). The cushions were also twice as compact at the high‐elevation sites. After two growing seasons of artificial warming, seed production (35%), leaf length (7%) and width (13%), and specific leaf area (63%) significantly decreased in D. novae‐zelandiae plants; flower production was not significantly affected. Cushion plant morphology and reproduction were significantly affected by environmental drivers at their establishment sites, but all populations responded negatively to artificial warming of 1–3°C. Many cushion plants are considered keystone species because of their propensity to facilitate the growth and establishment of other plant species, the inferred negative effects of global warming on cushion plant species may have a cascading effect on other alpine plant groups.

Elevation matters: contrasting effects of climate change on the vegetation development at different elevations in the Bavarian Alps

Despite broad evidence that recent climate change considerably affects alpine-nival vegetation, there are only a few studies revealing climate-induced vegetation changes in all vegetation belts above the actual treeline. Here, we use historical and recent vegetation surveys from the Bavarian Alps (Germany) to examine biodiversity, structural and functional trait composition changes in subalpine, lower and higher alpine vegetation belts during the past 50 years. Although species richness did not change significantly in dense subalpine vegetation, immigration of species from lower elevations and increased environmental favorability for already present thermophilic species led to an increase of plant cover (+23 %). In low alpine plots, a significant increase in species richness and plant cover (+41 and +18 %, respectively) was detected, due to gap availability and low competitive ability of alpine species. The results of the three-table ordination technique (RLQ) revealed that in subalpine and low alpine plots species with traits that are advantageous under warmer conditions, such as higher specific leaf area, high stature and heavier seeds, significantly increased their frequencies and abundances. Floristic and vegetation changes of high alpine plots were contrasting to those found in the subalpine and the low alpine vegetation located both in the study region and close mountain ridges. Despite the temperature increase and sufficient availability of colonisation gaps for newcomers, species richness (−24 %) and plant cover (−25 %) significantly decreased, probably due to permafrost degradation (as a consequence of recent warming). Our results suggest that considering vegetation characteristics as well as environmental conditions of different vegetation belts above the treeline is critical to accurately understand the response of alpine vegetation to climate change.