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High Mountains (high + mountain)
Terms modified by High Mountains Selected AbstractsHigh mountains of the Japanese archipelago as refugia for arctic,alpine plants: phylogeography of Loiseleuria procumbens (L.) Desvaux (Ericaceae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009HAJIME IKEDA According to previous phylogeographic studies, high mountains at low latitudes are important areas for the study of the evolutionary history of arctic,alpine plants in surviving the Pleistocene climatic oscillations. To evaluate this hypothesis, we elucidated the genetic structure of the arctic,alpine plant, Loiseleuria procumbens, in the Japanese archipelago, which corresponds to one of the southernmost limits of its distribution, using 152 individuals from 17 populations that covered the entire distribution of the Japanese archipelago and Sakhalin, in addition to samples from Sweden. Based on 854 bp of chloroplast DNA, we detected eight haplotypes. Along with haplotype distribution, strong genetic differentiation between populations in central and northern Japan was elucidated by a neighbour-joining tree (100%) and spatial analysis of molecular variance (79%), which is consistent with other alpine plants in Japan, regardless of the species' range. In addition, the southernmost populations from northern Japan showed specific genetic structure, although the remaining areas of northern Japan and Sakhalin harboured an homogenous genetic structure. Our results suggest that the populations in central Japan persisted for a long time during the Pleistocene climatic oscillation and that genetic divergence occurred in situ, supporting our hypothesis in conjunction with a previous study of another arctic,alpine plant, Diapensia lapponica subsp. obovata. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 403,412. [source] Food habits of the wildcat (Felis silvestris) in a peculiar habitat: the Mediterranean high mountainJOURNAL OF ZOOLOGY, Issue 1 2003M. Moleón The feeding spectrum of the wildcat Felis silvestris Schreber, 1777 was studied in two sites with different ecological characteristics, both situated in the same Mediterranean environment in the high mountain of the Sierra Nevada National Park, south-east Spain, where the rabbit Oryctolagus cuniculus is absent. Scat analysis (n=101 faeces; n=402 prey items) showed that the diet is based on rodents, fundamentally wood mouse Apodemus sylvaticus, Mediterranean pine vole Microtus duodecimcostatus and south-western water vole Arvicola sapidus. Results showed strong differences between the two sites (,2=74.04, d.f.=5, P<0.001), that is a predominance of voles in the mesic Chico river, whereas mice are predominant in the xeric Tejos ravine. Red-legged partridge Alectoris rufa and carrion also played an important role, especially in biomass terms. The overall diet differed essentially from that of the Mediterranean region, which surrounds the study area, since in these areas rabbits constitute the primary prey. However, the diet of the mountain wildcats is similar to that in the Eurosiberian floral region, despite its distance from the Sierra Nevada. In conclusion, the Iberian wildcat seems to behave as a facultative specialist, since it prefers rabbits whenever they are available, but rodents constitute most of its diet if rabbits are scarce or absent. [source] Signals of range expansions and contractions of vascular plants in the high Alps: observations (1994,2004) at the GLORIA, master site Schrankogel, Tyrol, AustriaGLOBAL CHANGE BIOLOGY, Issue 1 2007HARALD PAULI Abstract High mountain ecosystems are defined by low temperatures and are therefore considered to react sensitively to climate warming. Responding to observed changes in plant species richness on high peaks of the European Alps, an extensive setup of 1 m × 1 m permanent plots was established at the alpine-nival ecotone (between 2900 and 3450 m) on Mount Schrankogel, a GLORIA master site in the central Tyrolean Alps, Austria, in 1994. Recording was repeated in a representative selection of 362 quadrats in 2004. Ten years after the first recording, we observed an average change in vascular plant species richness from 11.4 to 12.7 species per plot, an increase of 11.8% (or of at least 10.6% at a 95% confidence level). The increase in species richness involved 23 species (about 43% of all taxa found at the ecotone), comprising both alpine and nival species and was pronouncedly higher in plots with subnival/nival vegetation than in plots with alpine grassland vegetation. Only three species showed a decrease in plot occupancy: one was an annual species, one was rare, and one a common nival plant that decreased in one part of the area but increased in the uppermost part. Species cover changed in relation to altitudinal preferences of species, showing significant declines of all subnival to nival plants, whereas alpine pioneer species increased in cover. Recent climate warming in the Alps, which has been twice as high as the global average, is considered to be the primary driver of the observed differential changes in species cover. Our results indicate an ongoing range contraction of subnival to nival species at their rear (i.e. lower) edge and a concurrent expansion of alpine pioneer species at their leading edge. Although this was expected from predictive distribution models and different temperature-related habitat preferences of alpine and nival species, we provide first evidence on , most likely , warming-induced species declines in the high European Alps. The projected acceleration of climate warming raises concerns that this phenomenon could become the major threat to biodiversity in high mountains. [source] European Alpine moisture variability for 1800,2003INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2007G. van der Schrier Abstract Moisture availability for the European Greater Alpine region (GAR) (43°N,49°N and 4°E,19°E) for the period 1800,2003 is analyzed on the basis of maps of monthly self-calibrating Palmer Drought Severity Index (scPDSI) with a 10, × 10, spatial resolution. To represent the impact of seasonal snow cover on the water budget, a simple snow-accumulation and snowmelt model is added to the water balance calculations on which the (self-calibrating) Palmer Drought Severity Index is based. Over the region as a whole, the late 1850s into the 1870s and the 1940s to the early 1950s stand out as persistent and exceptionally dry periods, whereas the first two decades of the nineteenth century and the 1910s were exceptionally wet periods. Dividing the Greater Alpine Region into four subregions, with the subregions based on coherence of precipitation variability, we find a large degree of heterogeneity in the behavior of the drought index over the subregions. The driest summers on record, in terms of the amplitude of the index averaged over the Alpine region, are 1865 and 2003. In these years, 75.6% and 85.1% of the region was suffering from a moderate drought (or worse). The areas northwest of the high mountains were affected most severely in the 1865 drought, whereas the 2003 drought impacted all subregions more equally. By substituting climatological monthly mean temperatures, from the period 1961,1990, for the actual monthly means in the parameterization for potential evaporation, an estimate is made of the direct effect of temperature on drought. It is observed that a major cause for the vast areal extent of the area affected by the summer drought in the last decade is the high temperatures. Temperatures in the 12 months preceding and including the summer of 2003 explain an increase in the area percentage with moderate (or worse) drought of 31.2%. Copyright © 2006 Royal Meteorological Society [source] Landscape patterns of indicator plants for soil acidity in the Bavarian AlpsJOURNAL OF BIOGEOGRAPHY, Issue 10 2003Sebastian Schmidtlein Abstract Aim, Electronic distribution atlases and lists of ecological indicator values are becoming important tools in plant geography. In this contribution, we combine a geographical and an ecological data bank, and map out patterns of indicator value spectra (instead of single or average values) across a physiographically complex landscape. For our study, we select indicators of soil pH and carbonate content as key environmental factors that strongly affect overall plant diversity patterns in the temperate zone. Our goal is to relate the distribution and diversity of plant groups that are indicators of soil pH and carbonate content to environmental controls at the landscape-scale, and thus contribute to a causal understanding of species pools. Location, We studied the Bavarian Alps, which represent the German portion of the Northern Alps. Methods, Based on the existing floristic survey, we calculated relative frequencies of nine classes of indicator plants for soil pH and carbonate content in grid cells. The resulting attribute matrix (cells by indicator class frequencies) was subjected to principal components analysis and to k-means clustering. Results were compared and mapped out in the grid array of the whole region, resulting in continuous and discrete representations of species pool structure. We used a geographical information system to derive physiographical landscape properties from a geological map and a digital elevation model, and analysed their statistical relationship with the shapes of indicator spectra. Results and Main conclusions, Averages of indicator values for soil pH and carbonate content follow the geological structure quite closely. Surprisingly, the diversity of indicator plant groups does not appear to be a function of geological or topographic heterogeneity. Rather, it seems to be related to areas of high elevation with uniform geology. The effect is a matter of additional acidophytes in high mountain areas and, in the high calcareous Alps, extreme calciphytes, while species with intermediate requirements are rarer than usual. For explanation, we suggest two facts: (1) a frequent lack of mature soils at high elevations and (2) particularities in soil genetic processes occurring under the harsh climatic conditions of high mountains. [source] Why are very large herbivores absent from Australia?JOURNAL OF BIOGEOGRAPHY, Issue 4 2000A new theory of micronutrients Abstract Aim We propose a Megacatalyst Theory, based on the pivotal role of the micronutrients iodine (I), cobalt (Co) and selenium (Se), in answer to the body size anomaly of herbivores on different continents, and the previously unexplained absence of megaherbivores in certain environments. Location It is anomalous that megaherbivores are absent from Australia while present in even dry and nutrient-poor parts of southern Africa, and that they have been exterminated from the Americas, but not south-east Asia. Methods We hypothesize that I, Co and Se are micronutrients in quantity, but megacatalysts in effect, determining maximum body size and pace of life, hence whether energy is used by animals or fire. The Megacatalyst Theory suggests that the greater the reproductive rate and brain size relative to body size, the greater the probable demand for I, Co and Se. Results Balanced supply of I, Co and Se, within narrow tolerances, is elusive because of disparate cycles: I gravitates towards the sea, whereas Co and Se are concentrated in ultramafics and organic shales, respectively. Sufficiency of these micronutrients, at less than toxic concentrations, is vital for rapid metabolism and growth, particularly of the nervous system. Iodine controls thermogenesis, Co controls the gut fermentation supplying herbivores, and Se controls biochemical damage where both processes occur rapidly. The supply of Co allows vegetation to be metabolized instead of combusted, by promoting digestion of fibre by gut microbes. Herbivores demand I, Co and Se in greater concentrations than palatable plants necessarily contain, as an increasing proportion of energy is fermented from fibre with increasing body size. Economy of scale is limited by loss of I in urine (partly compensated by thyroid size), Co in faeces (partly compensated by gut compartments), and Se both ways. Main conclusions The larger the herbivore species, the more it may depend on supplementation in order to survive predation by humans. As body mass increases, Co becomes deficient before I, because it is essential for rumination, and cannot be absorbed by the skin. Moderate uplift of a fairly flat landscape sustainably supplies I from mineralized springs, and Co from rocks (and Se from both), avoiding the excess of I in the sea and the excess of Co on high mountains. Iodine and Se leached to groundwater under dry climates are inaccessible to herbivores on a continent as flat as Australia, where even kangaroos have limited fecundity and intelligence compared to southern African ruminants of similar body mass. Where springs and associated earth-licks were available in the late Pleistocene, megaherbivores could evolve to survive the era of domestication. [source] Fluid evolution and thermal structure in the rapidly exhuming gneiss complex of Namche Barwa,Gyala Peri, eastern Himalayan syntaxisJOURNAL OF METAMORPHIC GEOLOGY, Issue 9 2005D. CRAW Abstract High-grade gneisses (amphibolite,granulite facies) of the Namche Barwa and Gyala Peri massifs, in the eastern Himalayan syntaxis, have been unroofed from metamorphic depths in the late Tertiary,Recent. Rapid exhumation (2,5 mm year,1) has resulted in a pronounced shallow conductive thermal anomaly beneath the massifs and the intervening Tsangpo gorge. The position of the 300 °C isotherm has been estimated from fluid inclusions using CO2,H2O immiscibility phase equilibria to be between 2.5 and 6.2 km depth below surface. Hence, the near-surface average thermal gradient exceeds 50 °C km,1 beneath valleys, although the thermal gradient is relatively lower beneath the high mountains. The original metamorphic fluid in the gneisses was >90% CO2. This fluid was displaced by incursion of brines from overlying marine sedimentary rocks that have since been largely removed by erosion. Brines can exceed 60 wt% dissolved salts, and include Ca, Na, K and Fe chlorides. These brines were remobilized during the earliest stages of uplift at >500 °C. During exhumation, incursion of abundant topography-driven surface waters resulted in widespread fracture-controlled hydrothermal activity and brine dilution down to the brittle,ductile transition. Boiling water was particularly common at shallow levels (<2.5 km) beneath the Yarlung Tsangpo valley, and numerous hot springs occur at the surface in this valley. Dry steam is not a major feature of the hydrothermal system in the eastern syntaxis (in contrast to the western syntaxis at Nanga Parbat), but some dry steam fluids may have developed locally. [source] The Upper Pleistocene to Holocene sediments on the Mediterranean island of Lampedusa (Italy)JOURNAL OF QUATERNARY SCIENCE, Issue 6 2004C. Giraudi Abstract The island of Lampedusa lies on the northern edge of the African continental shelf, but during some Quaternary marine lowstands it was joined to the African continent. The study and dating of the aeolian, alluvial, detrital sediments, calcareous crusts and speleothems have established that the climatic,environmental variations recorded on the island can be related chronologically to those known for northern Libya, Tunisia and the Italian peninsula. During the Last Glacial Maximum, phases of Saharan dust accumulation on Lampedusa occurred, and were coeval with dust accumulation in crater lakes and on high mountains in central-southern Italy, and with phases of glacial advance in the Apennines and in the Alps. During the late Holocene, accumulation of Saharan dust on Lampedusa occurred but there was little accumulation of dust on the northern side of the Mediterranean Sea. With the new data from Lampedusa, it is possible to envisage two different scenarios of atmospheric circulation relating to the Last Glacial Maximum and to the late Holocene. During the Last Glacial Maximum, southerly atmospheric circulation brought rainfall to the southern slopes of the Alps and to the Apennines. During the late Holocene, a prevalent westerly atmospheric circulation became established in the northern Mediterranean. Copyright © 2004 John Wiley & Sons, Ltd. [source] Local variation of haemoparasites and arthropod vectors, and intestinal protozoans in spiny mice (Acomys dimidiatus) from four montane wadis in the St Katherine Protectorate, Sinai, EgyptJOURNAL OF ZOOLOGY, Issue 1 2006A. Bajer Abstract Haemoparasite infections and infestations with potential arthropod vectors were assessed in spiny mice Acomys dimidiatus from four wadis in the arid montane region of the southern Sinai in Egypt in late summer 2000. Five taxa of haemoparasites (Haemobartonella spp. 80%, Hepatozoon sp. 20.6%, Trypanosoma acomys 17.5%, Bartonella spp. 2.5% and Babesia sp. 1.9%) were recorded. Additionally, infections with two intestinal protozoa, Cryptosporidium cf. parvum and Giardia sp., were quantified, both with similar prevalence (17.0 and 17.6%, respectively). 17.9% of mice carried fleas (Parapulex chephrensis and Xenopsylla dipodilli) and 32.1% had lice (Polyplax oxyrrhyncha and Polyplax brachyrrhycha combined). Marked differences in the prevalence and abundance of infections were detected between the four wadis, particularly with respect to T. acomys, Hepatozoon sp. and fleas, which were largely aggregated in just two of the four sites (Wadis Gharaba and Tlah). In contrast, the intestinal protozoa were more common, and abundance was higher, in Wadi El Arbaein. Intrinsic factors also contributed to a variation in prevalence, with strong age-dependent increases in the prevalence and abundance of Hepatozoon sp., higher mean species richness, prevalence of Cr. cf. parvum, and abundance of Giardia sp. and Hepatozoon sp. in female mice. Haemobartonella spp. showed an age-dependent reduction in abundance and higher abundance among male mice. A weak association was found between the prevalence of T. acomys and its putative flea vector. The single extrinsic factor in the study, site of capture, was more important than the intrinsic factors in explaining variation in the prevalence and abundance of haemoparasites, intestinal protozoa and arthropod vectors. In the high mountains of southern Sinai, the parasite fauna of spiny mice is distinct in each wadi, and hence we expect the parasites to exert spatially different co-evolutionary pressures on their hosts, with a resultant variation in host life histories. [source] Genetic consequences of Pleistocene range shifts: contrast between the Arctic, the Alps and the East African mountainsMOLECULAR ECOLOGY, Issue 12 2007DOROTHEE EHRICH Abstract In wide-ranging species, the genetic consequences of range shifts in response to climate change during the Pleistocene can be predicted to differ among different parts of the distribution area. We used amplified fragment length polymorphism data to compare the genetic structure of Arabis alpina, a widespread arctic-alpine and afro-alpine plant, in three distinct parts of its range: the North Atlantic region, which was recolonized after the last ice age, the European Alps, where range shifts were probably primarily altitudinal, and the high mountains of East Africa, where the contemporary mountain top populations result from range contraction. Genetic structure was inferred using clustering analyses and estimates of genetic diversity within and between populations. There was virtually no diversity in the vast North Atlantic region, which was probably recolonized from a single refugial population, possibly located between the Alps and the northern ice sheets. In the European mountains, genetic diversity was high and distinct genetic groups had a patchy and sometimes disjunct distribution. In the African mountains, genetic diversity was high, clearly structured and partially in accordance with a previous chloroplast phylogeography. The fragmented structure in the European and African mountains indicated that A. alpina disperses little among established populations. Occasional long-distance dispersal events were, however, suggested in all regions. The lack of genetic diversity in the north may be explained by leading-edge colonization by this pioneer plant in glacier forelands, closely following the retracting glaciers. Overall, the genetic structure observed corresponded to the expectations based on the environmental history of the different regions. [source] Permafrost monitoring in the high mountains of Europe: the PACE Project in its global contextPERMAFROST AND PERIGLACIAL PROCESSES, Issue 1 2001Charles Harris Abstract This paper introduces the structure and organization of permafrost monitoring within global climate-related monitoring programmes. The five-tiered principle proposed for the Global Hierarchical Observing Strategy (GHOST) is applied to the Global Terrestrial Network for Permafrost (GTN-P) monitoring system, and the European network of mountain permafrost boreholes established by the PACE project is discussed in the context of GTN-P. Borehole design and standard PACE instrumentation are described and some preliminary data from selected boreholes are presented. The broader research aims of the PACE programme include geophysical investigations, mapping and GIS strategies, numerical distribution modelling, physical modelling of thaw-related slope processes and mountain permafrost hazard assessment. Copyright © 2001 John Wiley & Sons, Ltd. RÉSUMÉ Le présent article décrit la structure et l'organisation du programme de surveillance du pergélisol et son intégration dans les programmes de surveillance du climat. Le principe à 5 niveaux proposé pour la stratégie d'observation hiérarchique (GHOST) est appliquée au réseau global de surveillance terrestre du pergélisol (GTN-P). Le réseau européen de sondages dans le pergélisol établi par le projet PACE est discuté dans le contexte du GTN-P. La localisation des sondages et l'instrumentation standard de PACE sont décrites et quelques données préliminaires de certains sondages sélectionnés sont présentées. Les recherches du programme PACE comprennent des recherches géophysiques, des stratégies de cartographie et de systèmes d'information géographique, des modèles de distribution numérique, des modèles physiques des processus de versants en relation avec le dégel et enfin des estimations des risques liés au pergélisol de montagne. Copyright © 2001 John Wiley & Sons, Ltd. [source] Reproduction of an early-flowering Mediterranean mountain narrow endemic (Armeria caespitosa) in a contracting mountain islandPLANT BIOLOGY, Issue 4 2009R. García-Camacho Abstract Reproduction at population lower edges is important for plant species persistence, especially in populations on contracting high-mountain islands. In this context, the ability of plants to reproduce in different microhabitats seems to be important to guarantee seed production in stressful environments, such as Mediterranean high mountains. We hypothesised that the warmer and drier conditions at the lower edge would be deleterious for the reproduction of Armeria caespitosa, an early-flowering plant. In addition, reproductive plasticity along this mountain gradient may also be microhabitat-dependent. We studied factors affecting the reproductive success of A. caespitosa, an endemic of the Spanish Sistema Central. We considered a complex set of predictors, including phenology, plant size and environmental factors at different scales using generalised estimating equations and generalised linear models. Microhabitat, together with the position in the altitudinal gradient and inter-annual variability affected the reproduction of A. caespitosa. In addition, individuals with longer flowering periods (duration of flowering) had significantly lower fruit set and a higher number of unviable seeds; delayed flowering peaks favoured the production of both viable and unviable fruits. Microhabitat variability over an altitudinal range is relevant for the reproduction of A. caespitosa, and is more important at the lower edge of the altitudinal range, where the species faces the most adverse conditions. In addition, the ability to reproduce in different microhabitats might increase the chances of the species to cope with environmental uncertainties under on-going climate warming. Finally, reproduction of this early-flowering plant is constrained by summer drought, which might shape its reproductive phenology. [source] Investigation by solid-phase microextraction and gas chromatography/mass spectrometry of secondary metabolites in lichens deposited on stone monumentsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2003Francesco De Angelis Lichens are ubiquitous organisms formed by symbiotic associations of fungal hyphas and algae that also grow under often extreme environmental conditions. They produce secondary metabolites, the so-called lichen substances, whose structural characterization can give an important contribution to lichen taxonomy. Lichens are also widely employed as biomonitors of atmospheric pollution; being epiphyte organisms they tend, in fact, to accumulate exogenous compounds. Moreover, it could be questioned if the environmental stress alters their secondary metabolites production. Therefore, a new strategy for the analysis of the organic substances absorbed or metabolized by lichens has been developed. This method exploits the dry solid-phase microextraction (SPME) headspace technique coupled with gas chromatography/mass spectrometry (GC/MS). Lichens coating the stone surfaces of monuments, located in small towns between high mountains and far away from urban environments, have been investigated. In the field of cultural heritage, this study can contribute to the knowledge of the state of conservation of outdoor exposed historical monuments. Copyright © 2003 John Wiley & Sons, Ltd. [source] Spatial Analysis and Surname Analysis: Complementary Tools for Shedding Light on Human Longevity PatternsANNALS OF HUMAN GENETICS, Issue 2 2008A. Montesanto Summary Starting from the observation that human longevity patterns show regional variations, we applied Spatial Analysis (using the Geographic Information System) and Surname Analysis to highlight the effect of the population genetic structure on such patterns. The study was carried out in Calabria, a southern Italian region which is characterized by a wide variability of geographic features (high mountains and deep valleys which created geographic isolates in the past). We identified three zones of high longevity: a male and a female longevity zone were located near the town of Cosenza (northern Calabria), while a male longevity zone was located in a mountainous and quite isolated part of the province of Reggio Calabria (southern Calabria). The latter zone was characterized by the lowest Female/Male ratio in nonagenarians observed to date. By applying surname analysis (Fisher's alpha) we found a significant negative correlation between surname abundance and index of longevity, showing that this isolated zone of male longevity presents a high level of inbreeding. On the whole, the results showed the effectiveness of spatial analysis in revealing geographical longevity patterns, and highlighted the importance of the population genetic structure in shaping such patterns. [source] The short history of infrared space telescopesASTRONOMISCHE NACHRICHTEN, Issue 6 2009D. Lemke Abstract While astronomical telescopes developed rather slowly over the last four centuries, infrared telescopes made a fast career in only four decades from high mountains to aircraft, balloons and satellites. They cover the huge wavelength region from 1 to 350 , m and have uncovered the cold and dust hidden universe. While until today all infrared space telescopes had diameters of <1 m, cooled infrared observatories with 3.5 to 6.5m mirrors will be sent into heliocentric orbits at L2 within the next few years (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] High mountains of the Japanese archipelago as refugia for arctic,alpine plants: phylogeography of Loiseleuria procumbens (L.) Desvaux (Ericaceae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009HAJIME IKEDA According to previous phylogeographic studies, high mountains at low latitudes are important areas for the study of the evolutionary history of arctic,alpine plants in surviving the Pleistocene climatic oscillations. To evaluate this hypothesis, we elucidated the genetic structure of the arctic,alpine plant, Loiseleuria procumbens, in the Japanese archipelago, which corresponds to one of the southernmost limits of its distribution, using 152 individuals from 17 populations that covered the entire distribution of the Japanese archipelago and Sakhalin, in addition to samples from Sweden. Based on 854 bp of chloroplast DNA, we detected eight haplotypes. Along with haplotype distribution, strong genetic differentiation between populations in central and northern Japan was elucidated by a neighbour-joining tree (100%) and spatial analysis of molecular variance (79%), which is consistent with other alpine plants in Japan, regardless of the species' range. In addition, the southernmost populations from northern Japan showed specific genetic structure, although the remaining areas of northern Japan and Sakhalin harboured an homogenous genetic structure. Our results suggest that the populations in central Japan persisted for a long time during the Pleistocene climatic oscillation and that genetic divergence occurred in situ, supporting our hypothesis in conjunction with a previous study of another arctic,alpine plant, Diapensia lapponica subsp. obovata. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 403,412. [source] Age and Provenance of Loess deposits on the Northern Flank of Tianshan MountainACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 3 2009Qingdong YUAN Abstract: The distribution, optically stimulated luminescence dating and granulometric properties suggest that the loess on the northern flank of Tian Shan should be divided into two types. One which is like mantle and is named type A, is located on the windward slopes and dated to about 54.5±5.73 Ka. The other, called type B, lies flatly on the terraces of the rivers or low hills and penetrated 30.8±2.05 Ka ago. Here we study the origin and the age of two types of loess, and a model of loess formation is proposed. The dust was entrained from the Gobi Desert located to the north of Tian Shan by the monsoon from Mongolia, obstructed by the high mountains and deposited on the windward slopes of the mountains. The rivers and flows then transported the aeolian loess to low terraces and piedmont alluvial plains. 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