Alpine Belt Research Articles

Diversity, Distribution, and Classification of Chasmophytic Vegetation in the Central Asian Biodiversity Hotspot: Alpine Belt of the Eastern Pamir-Alai and Western Tian Shan Mountains

AbstractThis paper presents the results of research conducted on chasmophytic vegetation occurring within the alpine belt (approx. 1,850–4,000 m a.s.l.) in the eastern part of Middle Asia. We specifically focused on the diversity and syntaxonomy of rock vegetation as well as on environmental variables determining its distribution. Altogether, 242 relevés were sampled in rock fissures, ledges, and clefts during field surveys conducted in 2013–2019. The size of each recorded vegetation plot was 1 m2. Five main groups of chasmophytic vegetation were distinguished in the studied area. Each group was confined to a specific combination of substrate type and climatic conditions. Altogether, 16 specific plant communities representing chasmophytic vegetation were defined in the study area. For each community diagnostic, constant and dominant species as well as its taxonomic composition and habitat characteristics are given. Seven communities were described: community ofAndrosace villosavar.dasyphylla, and associations ofCrepidifolio tenuifolii-Stipetum tianschanicae,Parryetum schugnanae,Corydalideto bucharicae-Hippolytietum schugnanicae,Drabetum darvasicae,Acantholimonetum alexeenkoani, andInuletum schmalhauseniiare newly coined. Due to the extremely high endemism of the chasmophytic flora of the eastern part of Middle Asia, it is difficult to find strong relationships between the rock vegetation recorded in the region and that occurring in neighboring areas.

Palaeoecological Interpretation of a Late Holocene Sediment Sequence from the Alpine Belt of the Southern Mongolian Altai Mountains

The climate in the Altai Mountains is determined by two major climate systems whose dominance has varied over time, leading to significant spatio-temporal changes in temperature and precipitation during the Holocene. This study aimed at the reconstruction of the local to regional moisture and temperature conditions in an alpine belt of the southern Mongolian Altai during the Late Holocene. It thereby contributes to a more comprehensive understanding of the region’s palaeoclimate in the Holocene. Our reconstruction is based on palynological and sediment analyses as well as radiometric age determinations of samples from a 130 cm exposed soil/sediment profile within the alpine belt. Largely supported by sedimentological and geochemical observations, the pollen assemblages indicate a warm and dry period between about 2600 and 2250 cal a BP, a subsequent cold and humid phase extending to about 130 cal a BP, and a return to warm and dry conditions lasting to present. Our data support the results of recent studies on the regional climate variability and the observation of significant differences in the mode of climate changes and its temporal sequence within the Altai Mountains. Although the pollen assemblages in the profile reflected a continuous anthropo-zoogenic influence on the study site’s vegetation climatic signals were clearly detectable, underlining the indicator value of the pollen data from the Alpine sediments for regional palaeoclimatic reconstruction.

Salix shrub encroachment along a 1000 m elevation gradient triggers a major ecosystem change in the European Alps

Shrub encroachment, a globally recognized response to climate warming, usually involves late successional species in mountain environments, without alteration to climax communities. We show that a major ecosystem change is occurring in the European Alps across a 1000 m elevation gradient, with pioneer hygrophilous Salix shrubs, previously typical of riparian forests, wetlands and avalanche ravines, encroaching into the climax communities of subalpine and alpine belts shrublands and grasslands, as well as snowbeds, pioneer vegetation and barren grounds in the nival belt.We analyzed Salix recruitment through dendrochronological methods, and assessed its relationships with climate and atmospheric CO2 concentration. The dendrochronological data indicated that Salix encroachment commenced in the 1950s (based on the age of the oldest Salix individuals, recruited in 1957), and that it was correlated with increasing atmospheric CO2 concentration, spring warming and snow cover decrease. Hygrophilous Salix shrubs are expanding their distribution both through range filling and upwards migration, likely achieving competitive replacement of species of subalpine and alpine climax communities. They benefit from climate warming and CO2 fertilization and are not sensitive to spring frost damage and soil limitations, being observed across a gradient of soil conditions from loose glacial sediments in recently deglaciated areas (where soils had not had sufficient time to develop) to mature soils such as podzols (when colonizing late successional subalpine shrublands).Salix encroachment may trigger ecosystem and landscape transformations, promoting the development of forests that replace pre‐existing subalpine shrublands, and of open woodlands invading alpine grasslands and snowbeds, making the alpine environment similar to sub‐Arctic and Arctic areas. This results in a new threat to the conservation of the plant species, communities and landscapes typical of the alpine biota, as mountain ranges such as the Alps provide limited opportunities for upward migration and range‐shift.

Spatial Heterogeneity of Uplift Pattern in the Western European Alps Revealed by InSAR Time‐Series Analysis

AbstractThe Western European Alps display measurable surface deformation rates from leveling and GNSS data. Based on the time‐series analysis of 4 years of Sentinel‐1 data, we propose for the first time an InSAR‐based mapping of the uplift pattern affecting the Western Alps on a ∼350 × 175‐km‐wide area. This approach provides a denser spatial distribution of vertical motion despite the high noise level inherent to mountainous areas and the low expected deformation signal. Our results show consistency with other geodetic measurements at the regional scale, and reveal smaller‐scale spatial variations in the uplift pattern. Higher uplift rates are found within the external crystalline massifs compared to surrounding areas, in agreement with the variations expected from recent deglaciation and long‐term exhumation data. This work brings the first InSAR‐based geodetic clue of differential uplift within the Alpine belt in response to the surface and deep processes affecting the belt.

Субфоссильные спорово-пыльцевые спектры как отражение высотной поясности Южного Сихотэ-Алиня

The correspondence of pollen spectra from surface soil samples from the Olkhovaya Mountain (height 1669 m) to vertical belt vegetation (coniferous-broadleaved forests, spruce-fir forests and golets belt) was analyzed. Attention is paid to the analysis of the pollen spectra formed under alpine vegetation, including spruce forests at an altitude of 1600 m and on a swampy area near the Alekseevskoye Lake, a unique alpine lake in the Southern Sikhote-Alin. Pollen of woody vegetation prevailed in subfossil spectra from all vegetation belts, the composition of pollen of herbaceous plants and spores was poor. 16 taxa of arboreal, 8 taxa of nonarboreal, 5 taxa of spores were identified. It was found that the ratio of the main taxa, in general, corresponds to the dominant plants of the vegetation cover. It is shown that the local vegetation is not fully reflected in the subfossil spectra in the alpine belt, especially there is little pollen from shrubs and grasses, and waterlogged habitats are poorly reflected. It was revealed which pollen from the leading plant families and genera of flora of the highlands is not reflected in the pollen spectra. It has been established how much allochthonous pollen and what taxa were carried by the wind from lower relief levels. Taxa with remote sources were found. In general, the pollen spectra from the Olkhovaya Mountain highlands reflect the widespread development of spruce forests near the peak. Presence of spruce forests and a small area of the alpine zone are the main reasons explaining why forest pollen spectra with a predominance of dark coniferous pollen were obtained above the forest boundary. The results obtained were compared with the data on subfossil spectra from soils and surface peat of the bogs of the Sergeevskoye and Shkotovskoye plateaus, as well as the Partizanskaya and the Kievka rivers basins. The data obtained are important for more correct paleogeographical reconstructions: biomization methods in the mountainous areas of the south Far East and the development of methodological techniques for assessing quantitative paleoclimatic parameters.

Lineaments Extraction and Analysis Using Landsat 8 (OLI/TIRS) in the Northeast of Morocco

Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. The presence of active faults in different directions explains the high tectonic instability and the high frequency of earthquakes. This study contributes to the effort of understanding the geothermal potential of the Northeast of Morocco. Heat source and permeability are both key factors in the geothermal process. Indeed, lineaments analysis constrains the structures and their directions and indicates severely faulted zones, which are the most promising areas for geothermal exploration. For this purpose, we used Landsat data combined with geological and structural maps available in this region. Different image processing techniques were applied including band ratio (6/2) and directional filters. To validate the results, we conducted a comparative study between linear structures, available geological data, and previous studies. Results of the automatic extraction method of lineaments from Landsat 8 OLI/TIRS indicate three main lineament systems: 1) a NE-SW system ranging from N40 to N70; 2) an N-S system ranging from N10 to N45; 3) an EW to WNW-ESE systems ranging from N80 to N120. Most of lineaments extracted are localized in Kebdana, Amejjaou, Nador and Melilla regions. Compared to previous studies, the NE-SW system is consistent with an extensive period (Tortonian to Pliocene); the NW-SE system is consistent with the last compressive episode (Pliocene); the N-S system is consistent with the first compressive period (Late/End Tortonian).

Vegetation of the ultramafic mountain massif Rai-Iz (upper reaches of the Enga-Yu River, the Polar Urals, Russia)

The syntaxonomic diversity of vegetation in the upper reaches of the Enga-Yu River is described. The specificity of the vegetation in the study area was determined by the ubiquitous occurrence of ultramafic rocks, which contributed to an increase in the harshness of habitats due to the high concentration of heavy metals and the low calcium content. Unfavorable geochemical environments caused the absence of several common in this region species and in the same time the change of ecological preferences and ecological amplitude of other species. Within the lower and middle parts of the alpine belt, we distinguished and described for the first time 4 associations and 2 subassociations. Cladonio rangiferinae–Caricetum arctisibiricae ass. nov. with 2 subassociations (C. r.–C. a. typicum subass. nov., C. r.–C. a. dicranetosum acutifolii subass. nov.) we assigned to the class Loiseleurio procumbentis– Vaccinietea Eggler ex Schubert 1960. Asahineo chrysanthae–Racomitrietum lanuginosi ass. nov. is placed into the class Carici rupestris–Kobresietea bellardii Ohba 1974. Two associations were distinguished as provisional. Tephroserido tundricolae–Bistortetum ellipticae ass. prov. comprising snowbed vegetation, is not assigned yet to any higher unit. Festuco arcticae–Caricetum arctisibiricae ass. prov. comprises meadow communities, it is assigned to the class Juncetea trifidi Hadač in Klika et Hadač 1944 and order Juncetalia trifidi Daniёls 1994. It is not assigned to any alliance due to the shortage of data. The peculiarity of these provisional associations we explain by the influence of ultramafic rocks.

Годовая динамика температуры в почвенном покрове гольцовых пустынь Хибин (Мурманская область)

As part of comprehensive environmental research of the highest Arctic mountain (goltsovy) desert belt of the Khibiny, data were obtained on the annual temperature dynamics in fragmentary cushions of vegetation. Area of investigation was disposed on the plateau of Mt. Aikuayvenchorr (1059–1063 m a. s. l.) and Vudyavrchorr plateau (1023 m a. s. l.). The period with negative values of the average daily temperature of the litter prevailed in the annual cycle (more than 200 days or 58 %). The sum of positive and negative temperatures, the number of days with temperatures below 0, from 0 ̊C to +5 ̊C, from + 5 ̊C to + 10 ̊C and above + 10 ̊C in litters was determined. The differences in the annual temperature dynamics in the litters of the alpine belt for two areas of research located on the Aikuayvenchorr and Vudyavrchorr plateaus are shown.

Notes on Potentilla (Rosaceae) of Altai. 9. A new species from Kuraisky Ridge

Based on morphological characters, a new species Potentilla friesenii collected from alpine belt of Kuraisky Ridge (Altai Mts.) is described. The novelty belongs to Potentilla sect. Chrysanthae; it is most closely related to P. asiatica but differs from the latter by styles not or somewhat widened and smooth to slightly verrucose (vs. always somewhat widened and strongly verrucose) at base as well as the presence of numerous violet glands on sepals. Stability of these differences are confirmed by several years of observation in the wild and in introduction. Illustration of the new species, image of its type specimen, and distribution map are adduced; the area of P. asiatica within Altai Mts. is also presented. A novel morphological feature separating P. asiatica and P. chrysantha is found: staminal ring in P. asiatica (as well as in the new species) is dark violet while it is pale in P. chrysantha. The name P. asiatica is lectotypified.

Chronology of thrust propagation from an updated tectono-sedimentary framework of the Miocene molasse (western Alps)

Abstract. After more than a century of research, the chronology of the deformation of the external part of the western Alpine belt (France) is still controversial for the Miocene epoch. In particular, the poor dating of the foreland basin sedimentary succession hampers a comprehensive understanding of the deformation kinematics. Here we focus on the Miocene molasse deposits of the northern subalpine massifs, southern Jura, Royans, Bas-Dauphiné, Crest, and La Bresse sedimentary basins through a multidisciplinary approach to build a basin-wide tectono-stratigraphic framework. Based on sequence stratigraphy constrained by biostratigraphical, chemostratigraphical (Sr isotopes), and magnetostratigraphical data between the late Aquitanian (∼ 21 Ma) and the Tortonian (∼ 8.2 Ma), the Miocene molasse chronostratigraphy is revised with a precision of ∼ 0.5 Ma. The Miocene molasse sediments encompass four different paleogeographical domains: (i) the oriental domain outlined by depositional sequences S1a to S3 (∼ 21 to ∼ 15 Ma), (ii) the median domain characterized by sequences S2 to S5 (∼ 17.8 to ∼ 12 Ma), (iii) the occidental domain in which sequences S2a to S8 (∼ 17.8 to ∼ 8.2 Ma) were deposited, and (iv) the Bressan domain where sedimentation is restricted to sequences S6 to S8 (∼ 12 to ∼ 8.2 Ma). A structural and tectono-sedimentary study is conducted based on new field observations and the reappraisal of regional seismic profiles, thereby allowing the identification of five major faults zones (FZs). The oriental, median, and occidental paleogeographical domains are clearly separated by FZ1, FZ2, and FZ3, suggesting strong interactions between tectonics and sedimentation during the Miocene. The evolution in time and space of the paleogeographical domains within a well-constrained structural framework reveals syntectonic deposits and a westward migration of the depocenters, allowing for proposing the succession of three deformation phases at the western Alpine front. (i) The first is a compressive phase (P1) corresponding to thrusting above the Chartreuse oriental thrust (FZ1), which was likely initiated during the Oligocene and rooted east of Belledonne. This tectonic phase generated reliefs that limited the Miocene transgression to the east. (ii) The second is a ∼ WNW–ESE-directed compressive phase (P2) lasting between 18.05 ± 0.25 Ma and ∼ 12 Ma, with thrusts rooted in the Belledonne basal thrust. Thrusts were activated from east to west: the Salève (SAL) and Gros Foug (GF) thrusts and then successively FZ2, FZ3, FZ4, and FZ5. Along two WNW–ESE balanced cross sections the amount of horizontal shortening is of ∼ 6.3 to 6.7 km, corresponding to average shortening rates of ∼ 1.2 km Myr−1 and migration of the deformation toward the west at a rate of ∼ 2.9 km Myr−1. During ∼ 6 Myr, the Miocene Sea was forced to regress rapidly westwards in response to westward migration of the active thrusts and exhumation of piggyback basins atop the fault zones. Phase P2 thus deeply shaped the Miocene paleogeographical evolution of the area and appears as a prominent compressive phase at the scale of the western Alps from the Swiss molasse basin to the Rhodano–Provencal one. (iii) The third is a ∼ 300 m phase of uplift in the Bas-Dauphiné (P3) of probable Tortonian age (∼ 10 Ma), which would have induced southward sea retreat and been coeval with the folding of the Jura in the north and possibly with back-thrusting east of the Chartreuse massif.

Analysis of the Avifauna Structure in the Alpine Belt of the Northwestern Putorana Plateau, Central Siberia

Analysis of the Avifauna Structure in the Alpine Belt of the Northwestern Putorana Plateau, Central Siberia

Imaging structure and geometry of slabs in the greater Alpine area – a P-wave travel-time tomography using AlpArray Seismic Network data

Abstract. We perform a teleseismic P-wave travel-time tomography to examine the geometry and structure of subducted lithosphere in the upper mantle beneath the Alpine orogen. The tomography is based on waveforms recorded at over 600 temporary and permanent broadband stations of the dense AlpArray Seismic Network deployed by 24 different European institutions in the greater Alpine region, reaching from the Massif Central to the Pannonian Basin and from the Po Plain to the river Main. Teleseismic travel times and travel-time residuals of direct teleseismic P waves from 331 teleseismic events of magnitude 5.5 and higher recorded between 2015 and 2019 by the AlpArray Seismic Network are extracted from the recorded waveforms using a combination of automatic picking, beamforming and cross-correlation. The resulting database contains over 162 000 highly accurate absolute P-wave travel times and travel-time residuals. For tomographic inversion, we define a model domain encompassing the entire Alpine region down to a depth of 600 km. Predictions of travel times are computed in a hybrid way applying a fast TauP method outside the model domain and continuing the wave fronts into the model domain using a fast marching method. We iteratively invert demeaned travel-time residuals for P-wave velocities in the model domain using a regular discretization with an average lateral spacing of about 25 km and a vertical spacing of 15 km. The inversion is regularized towards an initial model constructed from a 3D a priori model of the crust and uppermost mantle and a 1D standard earth model beneath. The resulting model provides a detailed image of slab configuration beneath the Alpine and Apenninic orogens. Major features are a partly overturned Adriatic slab beneath the Apennines reaching down to 400 km depth still attached in its northern part to the crust but exhibiting detachment towards the southeast. A fast anomaly beneath the western Alps indicates a short western Alpine slab whose easternmost end is located at about 100 km depth beneath the Penninic front. Further to the east and following the arcuate shape of the western Periadriatic Fault System, a deep-reaching coherent fast anomaly with complex internal structure generally dipping to the SE down to about 400 km suggests a slab of European origin limited to the east by the Giudicarie fault in the upper 200 km but extending beyond this fault at greater depths. In its eastern part it is detached from overlying lithosphere. Further to the east, well-separated in the upper 200 km from the slab beneath the central Alps but merging with it below, another deep-reaching, nearly vertically dipping high-velocity anomaly suggests the existence of a slab beneath the eastern Alps of presumably the same origin which is completely detached from the orogenic root. Our image of this slab does not require a polarity switch because of its nearly vertical dip and full detachment from the overlying lithosphere. Fast anomalies beneath the Dinarides are weak and concentrated to the northernmost part and shallow depths. Low-velocity regions surrounding the fast anomalies beneath the Alps to the west and northwest follow the same dipping trend as the overlying fast ones, indicating a kinematically coherent thick subducting lithosphere in this region. Alternatively, these regions may signify the presence of seismic anisotropy with a horizontal fast axis parallel to the Alpine belt due to asthenospheric flow around the Alpine slabs. In contrast, low-velocity anomalies to the east suggest asthenospheric upwelling presumably driven by retreat of the Carpathian slab and extrusion of eastern Alpine lithosphere towards the east while low velocities to the south are presumably evidence of asthenospheric upwelling and mantle hydration due to their position above the European slab.

BRYOFLORA OF THE SHOSHONE NATIONAL FOREST, WYOMING. PART 1. A CATALOGUE OF MOSSES AND LIVERWORTS OF THE BEARTOOTH PLATEAU AREA

This work is the first in a series of catalogues on the bryophytes of the oldest National Forest of the USA, the Shoshone National Forest. Bordering Yellowstone National Park and being a part of the Greater Yellowstone System, the Forest has retained a wide spectrum of its pristine representative areas, which support a unique bryophyte flora. Based on over 4600 specimens, the catalogue of the bryophytes of the Wyoming's Beartooth Plateau, the northernmost territories of the Forest, has been produced. This bryoflora is composed of 282 species (45 liverworts and 237 mosses) in the study area, representing approximately 53% of the Wyoming bryophyte flora. The richness of the flora is due to the high diversity of habitats, caused by the geological history of this portion of the Central Rocky Mountains, location of the study area essentially in the subalpine and alpine belts, climatic and hydrologic features, and low anthropogenic disturbance. The high elevations and associated habitat conditions allow for many disjunct arctic-alpine species (approximately 25% in the bryophyte flora). Remarkable extensions of upper elevation limits for 72 taxa are registered. Fifteen species, two subspecies, and two varieties of liverworts, as well as 56 species and eight varieties of mosses have not previously been reported for Wyoming in Flora of North America and Synopsis of Liverwort Flora of North America North of Mexico. Thirty-nine taxa (five species of liverworts and 32 species and two varieties of mosses) are of potential conservation concern in Wyoming, including two rare species with Pacific coastal affinities, Philonotis yezoana Besch. & Cardot and Sphagnum miyabeanum Warnst., and one species of extreme northern habitats, Sciuro-hypnum glaciale (Schimp.) Ignatov & Huttunen, being a novelty for continental North America. Brachythecium erythrorrhizon Schimp. var. alpinum Kosovich-Anderson & Ignatov was recently described, using material collected as part of this study.

Current state of populations of Rhodiola rosea L. (Crassulaceae) in East Kazakhstan

BackgroundBased on world experience, first, a modern assessment of the flora is needed to develop strategies for the conservation of ecosystems of rare and endangered plant species. A regional and global biodiversity strategy should focus on assessing the current state of bioresources. To preserve the biodiversity of the species and its habitat, we evaluated botanical features, ontogenetic phases, the ecological and phytocenotic structure of the rare and endangered of Rhodiola rosea L. (golden rose root) populations from the highlands of Eastern Kazakhstan.ResultsR. rosea in the study region lives on damp mossy rocks, rocky slopes, overgrown moraines and along the banks of mountain rivers in the upper limit of cedar-larch forests, subalpine and alpine belts, in the altitude limit of 1700–2400 m. In the studied region, R. rosea begins to vegetate in May–June, blooms in June–July, the fruits ripen in August. The species is encountered in the high mountain ranges of the Kazakh Altai and Saur-Tarabagatai. Unfavorable habitat conditions for the species are overgrown by sedge-grass and birch-moss communities. The most common species at sites with R. rosea are: Schulzia crinita, Achillea ledebourii, Doronicum altaicum, Macropodium nivale, Hylotelephium telephium, Rhodiola algida, Carex capillaris, C. aterrima. Ontogenetic study revealed that all age-related phases were present, with the exception of the senile states. Individual life expectancy shown to be 50–55 years. The analysis of the species composition in the communities with R. rosea showed that the leading families in terms of the number of accompanying species are Poaceae, Ranunculaceae, Asteraceae, Rosaceae and Caryophyllaceae, Apiaceae, Fabaceae; while the most dominant genera are: Carex, Aconitum, Dracocephalum, Festuca, Pedicularis, Poa, Salix; the ecological groups are dominated by psychrophytes, mesophytes mesopsychrophytes; the Asian, Eurasian, and Holarctic groups are the most represented groups. Dominant life forms according to Serebyakov were rod-rooted, brush-rooted, short-rooted and long-rooted grasses, while based on Raunkiaer’s groups the overwhelming majority consisted of Hemincryptophytes (74%).ConclusionsThe R. rosea populations of Kazakhstan represent an important gene stock of the species. Our study provides new insights into the species’ biology thus contributes to the conservation of biodiversity on a wide spatial scale.

Geology of the Piemonte-Ligurian units of the Urtier area (Northwestern Alps – Italy)

ABSTRACT Detailed geological mapping of the Urtier Valley in the Western Alps allowed to realize a new geological map 1:10.000 in scale. In the mapped area, a complete nappe stack of the axial part of the Alpine belt crops out. The study focused on the two units derived from the Piemonte-Ligurian oceanic domain, Broillot and Bardonney units, for which, in addition to the classic petrographic and structural considerations, a lithostratigraphic approach was applied. The lithostratigraphic approach, combined with structural analysis, led to reconstruct a nappe stacking significantly different from that generally proposed for the Western Alps. In the Urtier Valley in fact, the eclogite facies units are at the top of the nappe pile, overlapped on the blueschist facies units. This anomalous stacking order could be explained by interpreting the study area as an inverted limb of a regional fold with the eclogite facies units at the core.

New geochemical and geochronological data on the Cenozoic Veneto Volcanic Province: Geodynamic inferences

The Veneto Volcanic Province (VVP; NE Italy) is an intraplate magmatic area whose activity occurred intermittently in the Cenozoic, generating five districts (Val d'Adige, Lessini Mts., Marostica Hills, Berici Hills, and Euganean Hills). This intraplate magmatism was concomitant to the collision of the European plate and Adria microplate and the orogenesis of the neighboring Alpine belt. Different geodynamic models suggested relationships between VVP and the coexisting subduction processes. To give new insights on this on-going debate, this work provides new petrographic and geochemical data, including Sr-Nd-Pb isotopic and 40Ar/39Ar and KAr geochronological analyses for lavas sampled in the Lessini Mts. and Val d'Adige, which are the oldest VVP magmatic districts, as well as Marostica Hills and Berici Hills, which are the least investigated districts. The trace element distribution indicates that VVP melts were variously affected by metasomatic enrichments stabilized as phlogopite and/or amphibole. The Sr-Nd-Pb isotope ratios conform to the dominant features of sub-lithospheric mantle components widespread at regional scale throughout the whole European and Mediterranean area. Within this framework, the geochronological data indicate that the oldest magmatic episodes occurred in the Eocene (45–42 Ma) in the Lessini Mts. and Val d'Adige, simultaneously with the orogenic magmatism of Adamello intrusive complex along the Giudicarie Fault, a portion of the Periadriatic lineament which is an important Alpine suture. In our geodynamic reconstruction we propose that the Giudicarie Fault is the superficial expression of a slab tear, responsible for the uprising of an asthenospheric poloidal mantle flow, which induced both the Adamello and VVP magmatism. Subsequently, VVP activity migrated eastwards following the general mantle flow as indicated by minor volcanic pulses in the Euganean and Marostica Hills during Oligocene and Miocene.

Variation in biomass and nutrients allocation of Corydalis hendersonii on the Tibetan Plateau with increasing rainfall continentality and altitude

The Tibetan Plateau is considered as one of most sensitive region to global change. Nutrient (N and P) availability is an important limiting ecological factor in cold terrestrial ecosystems such as the alpine belt of the Tibetan Plateau. We focused on Corydallis hendersonii, an endemic alpine species of the Tibetan Plateau. Exploring the N and P below- and above-ground responses of C. hendersonii to climatic factors is crucial for biodiversity conservation of the alpine Tibetan plateau under global change. We used the Outlying Mean Index and regression analyses to assess N and P stoichiometry and biomass responses in leaves and roots of C. hendersonii along climatic gradients. We found that investment and allocation of nutrient and biomass in C. hendersonii were mainly driven by rainfall continentality. In the eastern less-continental wet area of the Tibetan plateau, C. hendersonii had higher biomass in leaf, and lower N and P investment in roots than in the western more continental dry part. Specifically, 300 mm year−1 Mean annual precipitation (MAP) and ca. 80° Rainfall continentality index (GAMS) were threshold values of climate stress inducing strong nutrient limitation for C. hendersonii across the Tibetan Plateau. Our results suggest that rainfall continentality is the primary climatic driver of variation in biomass and nutrients allocation of C. hendersonii on the Tibetan Plateau. Thus, global warming and drying should induce a decrease in total biomass, a reduction in leaf N and P concentrations and an increase in root/shoot ratio in the alpine region of the Tibetan Plateau.

Palaeovegetation and climatic variations in the Parvati Valley, Himachal Pradesh, India since last deglaciation

Pollen proxy records from 1.2 m deep sediment profile from Tundabhuj, Parvati Valley (H.P.) reveals that between 15,260 and 13,280 yr BP, the sub–alpine belt supported alpine–scrub vegetation dominated by Betula and thermophillous broad–leaved allies viz. Quercus, Corylus and Carpinus, interspersed with meadows comprising grasses, Asteraceae, Impatiens, etc. under a warm and moderately moist climate. The dry scrubby element, Juniperus occurred in restricted pockets on the sunny mountain slopes. The frequent record of conifers such as Pinus cf. wallichiana, Cedrus, Abies and Picea implies the proximity of the temperate belt to the study site. Around 13,280 to 7,340 yr BP, the considerable expansion of Betula and broad–leaved allies and a simultaneous reduction in Juniperus elucidate the replacement of alpine scrub forests by temperate Betula–broad–leaved forest in response to onset of a relatively warm and more–moist climate. This change occurred by the upward shift of the timber line as reflected by the improvement in the conifers. The climate deteriorated and turned cold and dry around 7,340 to 5,030 yr BP as manifested by the abrupt reduction in the alpine–scrub vegetation and meadow constituents. Subsequently, between 5,030 and 2,000 yr BP this region witnessed a warm and moist climate again as evidenced from moderate expansion in the alpine–scrubs and conifers. Since 2,000 yr BP onwards deterioration in climate is demonstrated by the depletion in Betula and broad–leaved associates and substantial increase in Juniperus and Ephedra.

Why Is the Alpine Flora Comparatively Robust against Climatic Warming?

The alpine belt hosts the treeless vegetation above the high elevation climatic treeline. The way alpine plants manage to thrive in a climate that prevents tree growth is through small stature, apt seasonal development, and ‘managing’ the microclimate near the ground surface. Nested in a mosaic of micro-environmental conditions, these plants are in a unique position by a close-by neighborhood of strongly diverging microhabitats. The range of adjacent thermal niches that the alpine environment provides is exceeding the worst climate warming scenarios. The provided mountains are high and large enough, these are conditions that cause alpine plant species diversity to be robust against climatic change. However, the areal extent of certain habitat types will shrink as isotherms move upslope, with the potential areal loss by the advance of the treeline by far outranging the gain in new land by glacier retreat globally.

Notes on the distribution, ecology, associated vegetation and conservation status of Gymnadenia (Orchidaceae) in Kosovo

Four species of Gymnadenia are native to Kosovo: G. conopsea, G. frivaldii, G. nigra, and G. odoratissima. In this study, field expedition data, phytosociological relevés, herbarium specimens along with extensive literature sources were used to analyse vegetation and ecological characteristics, habitat types, distributional patterns as well as provide notes on conservation. Gymnadenia conopsea is distributed throughout the country, from lowlands to the alpine belt. It was recorded in various plant communities. Gymnadenia frivaldii grows in the alpine zone of mountains, close to streams and in wet meadows. Its relevés belong to the class Scheuchzerio-Caricetea fuscae. This species is classified as “Near Threatened” (NT) in Kosovo. Gymnadenia nigra grows in subalpine and alpine grassland on preferably calcareous substrate. It has been found in almost all mountains reaching >2000 m a.s.l., and occurs in different plant communities belonging to the class: Elyno-Seslerietea. Gymnadenia odoratissima was recorded from one locality only in Kosovo, on the massif of Maja e Zezë, Sharri Mts. It was growing in degraded beech forest and meadows on silicate bedrock. Its floristically diverse relevés associate with the class: Mulgedio-Aconitetea. Of the four studied species, G. frivaldii deserves more conservation attention because of its fragile populations.