Fruticose and Foliose Lichens of the High-Mountain Areas of the Southern Appalachians

1978 ◽  
Vol 81 (1) ◽  
pp. 1 ◽  
Author(s):  
Jonathan P. Dey
Keyword(s):  
Southern Appalachians ◽  
High Mountain ◽  
Mountain Areas

scholarly journals Formation Patterns of Mediterranean High-Mountain Water-Bodies in Sierra-Nevada, SE Spain

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 438
Author(s):  
Jose Luis Diaz-Hernandez ◽  
Antonio Jose Herrera-Martinez
Keyword(s):  
Sierra Nevada ◽  
Unknown Origin ◽  
Slope Instability ◽  
Water Bodies ◽  
High Mountain ◽  
Mountain Areas ◽  
Glacial Processes ◽  
The Mediterranean ◽  
Water Volumes

At present, there is a lack of detailed understanding on how the factors converging on water variables from mountain areas modify the quantity and quality of their watercourses, which are features determining these areas’ hydrological contribution to downstream regions. In order to remedy this situation to some extent, we studied the water-bodies of the western sector of the Sierra Nevada massif (Spain). Since thaw is a necessary but not sufficient contributor to the formation of these fragile water-bodies, we carried out field visits to identify their number, size and spatial distribution as well as their different modelling processes. The best-defined water-bodies were the result of glacial processes, such as overdeepening and moraine dams. These water-bodies are the highest in the massif (2918 m mean altitude), the largest and the deepest, making up 72% of the total. Another group is formed by hillside instability phenomena, which are very dynamic and are related to a variety of processes. The resulting water-bodies are irregular and located at lower altitudes (2842 m mean altitude), representing 25% of the total. The third group is the smallest (3%), with one subgroup formed by anthropic causes and another formed from unknown origin. It has recently been found that the Mediterranean and Atlantic watersheds of this massif are somewhat paradoxical in behaviour, since, despite its higher xericity, the Mediterranean watershed generally has higher water contents than the Atlantic. The overall cause of these discrepancies between watersheds is not connected to their formation processes. However, we found that the classification of water volumes by the manners of formation of their water-bodies is not coherent with the associated green fringes because of the anomalous behaviour of the water-bodies formed by moraine dams. This discrepancy is largely due to the passive role of the water retained in this type of water-body as it depends on the characteristics of its hollows. The water-bodies of Sierra Nevada close to the peak line (2918 m mean altitude) are therefore highly dependent on the glacial processes that created the hollows in which they are located. Slope instability created water-bodies mainly located at lower altitudes (2842 m mean altitude), representing tectonic weak zones or accumulation of debris, which are influenced by intense slope dynamics. These water-bodies are therefore more fragile, and their existence is probably more short-lived than that of bodies created under glacial conditions.

scholarly journals Trapping of Organochlorine Compounds in High Mountain Lakes

2001 ◽  
Vol 1 ◽  
pp. 609-611 ◽  
Author(s):  
Joan O. Grimalt ◽  
Pilar Fernandez ◽  
Rosa M. Vilanova
Keyword(s):  
Atmospheric Transport ◽  
Mountain Lakes ◽  
Organochlorine Compounds ◽  
High Mountain ◽  
High Latitudes ◽  
High Mountain Lakes ◽  
Mountain Areas ◽  
Persistent Pollutants

High mountain areas have recently been observed to be polluted by organochlorine compounds (OC) despite their isolation. These persistent pollutants arrive at these remote regions through atmospheric transport. However, the mechanisms involving the accumulation of these compounds from the atmospheric pool to the lacustrine systems still need to be elucidated. These mechanisms must be related to the processes involving the transfer of these pollutant from low to high latitudes[1] as described in the global distillation effect[2].

scholarly journals Mechanisms linking active rock glaciers and impounded surface water formation in high-mountain areas

2017 ◽  
Vol 43 (2) ◽  
pp. 417-431 ◽  
Author(s):  
Nicola Colombo ◽  
Luigi Sambuelli ◽  
Cesare Comina ◽  
Chiara Colombero ◽  
Marco Giardino ◽  
...  
Keyword(s):  
Surface Water ◽  
High Mountain ◽  
Mountain Areas ◽  
Water Formation ◽  
Rock Glaciers

Polycyclic Aromatic Hydrocarbons in Soils from European High Mountain Areas

2010 ◽  
Vol 215 (1-4) ◽  
pp. 655-666 ◽  
Author(s):  
Roberto Quiroz ◽  
Joan O. Grimalt ◽  
Pilar Fernandez ◽  
Lluis Camarero ◽  
Jordi Catalan ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
High Mountain ◽  
Mountain Areas ◽  
Polycyclic Aromatic ◽  
Hydrocarbons In Soils

scholarly journals Hypsugo stubbei sp. nov., a novel cryptic bat species of the genus Hypsugo (Vespertilionidae, Chiroptera, Mammalia) from Mongolia. Results of the Mongolian-German Biological Expeditions Since 1962, No. 347.

2021 ◽  
Author(s):  
Dietrich Dolch ◽  
Michael Stubbe ◽  
Nyamsuren Batsaikhan ◽  
Annegret Stubbe ◽  
Dirk Steinhauser
Keyword(s):  
High Mountain ◽  
Limited Data ◽  
Gene Encoding ◽  
Mountain Areas ◽  
Mitochondrial Coi ◽  
Subspecies Level ◽  
Western Palearctic ◽  
Close Proximity ◽  
Morphological Differences ◽  
Mitochondrial Nd1

The occurrence of two members of the genus Hypsugo, namely H. alaschanicus and H. savii caucasicus, have been reported for Mongolia in the literature. Due to various taxonomic reassignments within and between genera, the number of records for the genus Hypsugo in Mongolia is quite scarce and sometimes not resolved at species or subspecies level. Despite recognition of the two above-mentioned species, recent reports based on genetic analyses describe only new and further records of H. alaschanicus. Thus, it exists a large uncertainty regarding the occurrence and distribution of H. savii caucasicus in Mongolia. Here, our efforts in gaining a deeper understanding towards the occurrence and distribution of Hypsugo species in Mongolia are described. A combination of genetic and morphological analyses of collected material from Hypsugo specimens revealed the existence of a genetically largely distant Hypsugo clade. Therefore, a new and cryptic Hypsugo species is proposed which is named after Prof. Dr. Michael Stubbe for his continuous, long-standing and significant contributions into the biological exploration of Mongolia. Hypsugo stubbei sp. nov. differs by at least 8.4 % and 9 % to the closest Western Palearctic distributed H. cf. darwinii and H. savii as well as at least 11.3 % to the Easter Palearctic (including Mongolia) distributed H. alaschanicus based on the first 798 nucleotides of the gene encoding the mitochondrial ND1 (subunit one of NADH dehydrogenase). Neither a close proximity species based on the gene encoding the mitochondrial COI (cytochrome oxidase subunit one) could be found in publicly accessible nucleotide databases. While the cryptic H. stubbei sp. nov. reveals no obvious cranial and morphological differences, few external characteristics are dissimilar to both H. alaschanicus and H. savii (caucasicus). Currently, Hypsugo stubbei sp. nov. was found at four different locations in Mongolia. Among the 11 specimens captured, six facilitated a genetic assignment. Based on the current scarce data records, the species seems to occur mainly in the far west of Mongolia inhabiting semi-deserts and steppes up to high mountain areas. An overlapping distribution with H. alaschanicus cannot be excluded based on the limited data currently available.

scholarly journals Medieval Forest Dynamics in the Iberian Pyrenees: A Comparison Between Low- and High-mountain Areas

2021 ◽  
Author(s):  
Valentí Rull ◽  
Teresa Vegas-Vilarrúbia
Keyword(s):  
Bronze Age ◽  
Middle Ages ◽  
Forest Dynamics ◽  
Forest Conservation ◽  
Forest Recovery ◽  
High Mountain ◽  
Human Pressure ◽  
Anthropogenic Pressures ◽  
Mountain Areas ◽  
The Middle Ages

This paper compares the Medieval (ca. 400–1500 CE) dynamics of forests from low-mountain (Montcortès; ca. 1000 m a.s.l.) and high-mountain (Sant Maurici; 1900 m a.s.l.) areas of the Iberian Pyrenees, both of which experienced similar climatic forcing but different anthropogenic pressures. The main aim is to identify forest changes over time and associate them with the corresponding climatic and anthropogenic drivers (or synergies among them) to test how different forests at different elevations respond to external forcings. This could be useful to evaluate the hypothesis of general Pyrenean deforestation during the Middle Ages leading to present-day landscapes and to improve the background for forest conservation. The study uses palynological analysis of lake sediments, historical documents and paleoecological reconstructions based on pollen-independent proxies. The two sites studied showed different forest trajectories. The Montcortès area was subjected to intense human pressure during regional deforestation up to a maximum of ca. 1000 CE. Further forest recovery took place until the end of the Middle Ages due to a change in forest management, including the abandonment of slash-and-burn practices. Climatic shifts indirectly influenced forest trends by regulating human migrations and the resulting shifts in the type and intensity of forest exploitation. The highland Sant Maurici forests exhibited a remarkably long-standing constancy and an exceptional resilience to climatic shifts, which were unable to affect forest extension and composition, and to local human pressure, from which they rapidly recovered. The Montcortès and Sant Maurici records did not follow the rule of an irreversible forest clearing during the Middle Ages leading to present-day landscapes. The present Montcortès landscape was shaped after a Medieval forest recovery, a new Modern-Age deforestation and a further forest recovery during the last centuries. The Sant Maurici forests remained apparently untouched since the Bronze Age and were never cleared during the Middle Ages. The relevance of these findings for forest conservation is briefly addressed, and the need for the development of more high-resolution studies on Pyrenean forest dynamics is highlighted.

Using historical aerial imagery to assess multidecadal kinematics and elevation changes. Application to mountain permafrost in the French Alps.

2021 ◽  
Author(s):  
Diego Cusicanqui ◽  
Antoine Rabatel ◽  
Xavier Bodin ◽  
Christian Vincent ◽  
Emmanuel Thibert ◽  
...  
Keyword(s):  
Ice Core ◽  
Horizontal Displacement ◽  
Vertical Surface ◽  
Aerial Images ◽  
Surface Velocity ◽  
High Mountain ◽  
European Alps ◽  
Permafrost Degradation ◽  
Mountain Areas ◽  
Mountain Permafrost

<p>Glacial and periglacial environments are highly sensitive to climate change, even more in mountain areas where warming is faster and, as a consequence, perennial features of the cryosphere like glaciers and permafrost have been fast evolving in the last decades. In the European Alps, glaciers retreat and permafrost thawing have led to the destabilization of mountain slopes, threatening human infrastructures and inhabitants. The observation of such changes at decadal scales is often limited to sparse in situ observations.</p><p>Here, we present three study cases of mountain permafrost sites based on a multidisciplinary approach over almost seven decades. The goal is to investigate and quantify morphodynamic changes and understand the causes of these evolutions. We used stereo-photogrammetry techniques to generate orthophotos and (DEMs) from historical aerial images (available, in France since 1940s). From this, we produced diachronic comparison of DEMs to quantify vertical surface changes, as well as feature tracking techniques of multi-temporal digital orthophotos for estimating horizontal displacement rates. Locally, high-resolution datasets (i.e. LiDAR surveys, UAV acquisitions and Pléiades stereo imagery) were also exploited to improve the quality of photogrammetric products. In addition, we combine these results with geophysics (ERT and GPR) to estimate the ice content, geomorphological surveys to describe the complex environments and the relationship with climatic forcing.</p><p>The first study case is the Laurichard rock glacier, where we were able to quantify changes of emergence velocities, fluxes, and volume. Together with an acceleration of surface velocity, important surface lowering have been found over the period 1952-2019, with a striking spatiotemporal reversal of volume balance.</p><p>The second study site is the Tignes glacial and periglacial complex, where the changes of thermokarstic lakes surface were quantified. The results suggest that drainage probably affects the presence and the evolution of the largest thermorkarst. Here too, a significant ice loss was found on the central channel concomitant to an increase in surface velocities.</p><p>The third study site is the Chauvet glacial and periglacial complex where several historical outburst floods are recorded during the 20th century, likely related to the permafrost degradation, the presence of thermokarstic lakes, and an intra-glacial channel. The lateral convergence of ice flow, due to the terrain subsidence caused by the intense melting, may cause the closure of the channel with a subsequent refill of the thermokarstic depression and finally a new catastrophic event.</p><p>Our results highlight the important value of historical aerial photography for having a longer perspective on the evolution of the high mountain cryosphere, thanks to accurate quantification of pluri-annual changes of volume and surface velocity. For instance, we could evidence : (1) a speed-up of the horizontal displacements since the 1990s in comparison with the previous decades; (2) an important surface lowering related to various melting processes (ice-core, thermokarst) for the three study sites; (3) relationships between the observed evolution and the contemporaneous climate warming, with a long-term evolution controlled by the warming of the ground and short-term changes that may relate to snow or precipitation or to the activity of the glacial-periglacial landforms.</p>

scholarly journals Observing Snow Cover and Water Resource Changes in the High Mountain Asia Region in Comparison with Global Mountain Trends over 2000–2018

2020 ◽  
Vol 12 (23) ◽  
pp. 3913
Author(s):  
Claudia Notarnicola
Keyword(s):  
Water Resources ◽  
Confidence Interval ◽  
Snow Cover ◽  
Water Storage ◽  
High Mountain ◽  
Global Level ◽  
Total Water ◽  
Mountain Areas ◽  
Snow Cover Extent ◽  
The Impact

The quantification of snow cover changes and of the related water resources in mountain areas has a key role for understanding the impact on several sectors such as ecosystem services, tourism and energy production. By using NASA-Moderate Resolution Imaging Spectroradiometer (MODIS) images from 2000 to 2018, this study analyzes changes in snow cover in the High Mountain Asia region and compares them with global mountain areas. Globally, snow cover extent and duration are declining with significant trends in around 78% of mountain areas, and the High Mountain Asia region follows similar trends in around 86% of the areas. As an example, Shaluli Shan area in China shows significant negative trends for both snow cover extent and duration, with −11.4% (confidence interval: −17.7%, −5.5%) and −47.3 days (confidence interval: −70.4 days, −24.4 days) at elevations >5500 m a.s.l. respectively. In spring, an earlier snowmelt of −13.5 days (confidence interval: −24.3 days, −2.0 days) in 4000–5500 m a.s.l. is detected. On the other side, Tien Shan area shows an earlier snow onset of −28.8 days (confidence interval: −44.3 days, −8.2 days) between 2500 and 4000 m a.s.l., governed by decreasing temperature and increasing snowfall. In the current analysis, the Tibetan Plateau shows no significant changes. Regarding water resources, by using Gravity Recovery and Climate Experiment (GRACE) data it was found that around 50% of areas in the High Mountain Asia region and 30% at global level are suffering from significant negative temporal trends of total water storage (including groundwater, soil moisture, surface water, snow, and ice) in the period 2002–2015. In the High Mountain Asia region, this negative trend involves around 54% of the areas during spring period, while at a global level this percentage lies between 25% and 30% for all seasons. Positive trends for water storage are detected in a maximum 10% of the areas in High Mountain Asia region and in around 20% of the areas at global level. Overall snow mass changes determine a significant contribution to the total water storage changes up to 30% of the areas in winter and spring time over 2002–2015.

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