Rounded boulders at high altitudes along some Appalachian rivers

1887 ◽  
Vol s3-34 (203) ◽  
pp. 374-381 ◽  
Author(s):  
I. C. White
Keyword(s):  
2005 ◽  
Author(s):  
Sergey F. Gimelshein ◽  
Alina A. Alexeenko ◽  
Dean C. Wadsworth ◽  
Natalia E. Gimelshein

Author(s):  
Dean Jacobsen ◽  
Olivier Dangles

Chapter 2 presents the amazing variety of running waters, lakes, ponds, and wetlands found at high altitudes. These waterbodies are not equally distributed among the world’s high altitude places, but tend to be concentrated in certain areas, primarily determined by regional climate and topography. Thus, a large proportion of the world’s truly high altitude aquatic systems are found at lower latitudes, mostly in the tropics. The chapter presents general patterns in the geographical distribution of high altitude waters, and gives examples of some of the most extreme systems. High altitude aquatic systems and habitats cover a broad variety in dynamics and physical appearance. These differences may be related to, for example, water source (glacier-fed, rain-fed, or groundwater-fed streams), geological origin (e.g. glacial, volcanic, or tectonic lakes), or catchment slope and altitude (different types of peatland wetlands). This is exemplified and richly illustrated through numerous photos.


Author(s):  
Pradya Somboon ◽  
Thanari Phanitchakun ◽  
Jassada Saingamsook ◽  
Rinzin Namgay ◽  
Ralph E Harbach

Abstract Culex longitubus Somboon, Namgay & Harbach is described as a new species of the Mimeticus Subgroup of the subgenus Culex. The larva is most similar to the larva of Cx. tianpingensis Chen from China, but is distinguished by the length of the siphon and the anal papillae, the form of the comb scales and pecten spines, and the development of setae 7-P, 13-T, 1-X, and 4-X. The adults have wing markings and male genitalia similar to those of species of the Mimeticus Complex. Phylogenetic analysis of COI sequences revealed that the new species is closely related to Cx. murrelli Lien of the Mimulus Complex. The immature stages of the new species were found in stagnant pools and marshes at high altitudes in several districts of Bhutan.


1992 ◽  
Vol 24 (2) ◽  
pp. 111-117
Author(s):  
W. Obermayer ◽  
J. Poelt

Abstract The lichen Lecanora somervellii Paulson, first described from the northern slopes of Mt Everest in Tibet, has been collected at four other localities in the High Himalayas, at altitudes between 3750 and 5540 m. As the type material appears to be missing, a neotype is designated here. The species has an unusual lemon yellow colour due to the pigment calycin; this compound is in addition to usnic acid, which is widespread in Lecanora. Lecanora somervellii is otherwise very similar in essential characters to the complex including Lecanora concolor Ram. and L. orbicularis (Schaerer) Vainio, high alpine species well-known, for example, from the Alps. It is supposed, that L. somervellii is derived from this aggregate by the production of calycin (in addition to usnic acid), which acts as an additional protective pigment at these very high altitudes.


2021 ◽  
Vol 304-305 ◽  
pp. 108392
Author(s):  
Peng Zhou ◽  
Jian-Guo Huang ◽  
Hanxue Liang ◽  
Sergio Rossi ◽  
Yves Bergeron ◽  
...  

Author(s):  
Lingjiang Huang ◽  
Jian Kang

AbstractThe solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort. It can bring favorable passive solar heating and can result in undesired overheating (even in winter). This problem becomes more critical for high altitudes with high intensity of solar irradiance, while received limited attention. In this study, we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high altitudes. First, we evaluated the thermal comfort incorporating solar radiation effect in winter by field measurements. Subsequently, we investigated local occupant adaptive responses (considering the impact of direct solar irradiance). This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar adjustment. Finally, we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes, and evaluated thermal mass shading with solar louvers in terms of indoor environment control. The results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa, with over two-thirds of daytime beyond the comfort range. Further, various adaptive behaviors are adopted by occupants in response to overheating due to the solar radiation. Moreover, it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing curtains. The developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2% during the winter and a corresponding increase of comfort time.


1961 ◽  
Vol 16 (1) ◽  
pp. 141-143 ◽  
Author(s):  
Paul D. Altland

Chickens and pigeons were exposed for 6 hours to various simulated high altitudes to determine the highest altitude tolerated without deaths and the lowest altitude at which there are no survivors. Six- to seven-week-old chicks were less tolerant than twenty-to twenty-five-week-old chickens. All chicks survived exposure to 12,000 feet, 90% survived 14- and 16,000 feet and, at higher altitudes, the survival was progressively lower until none survived at 26,000 feet. All older chickens survived exposure to 16,000 feet; approximately 88% survived altitudes up to 20,000 feet and, above this, survival was greatly decreased until none survived at 26,000 feet. Roosters showed a greater altitude tolerance than hens, a sex difference contrary to that found in mammals. Six- to ten-week-old pigeons survived 6-hour exposures to all altitudes including 28,000 feet and 97% survived exposure to 30,000 feet. Only 27% survived 32,000 feet and all died within 10 minutes at 34,000 feet. The results indicate that chickens have a much lower altitude tolerance than all other small warm-blooded animals previously studied. Submitted on July 11, 1960


1957 ◽  
Vol 34 (9) ◽  
pp. 440 ◽  
Author(s):  
Luis Levy ◽  
Oswaldo E. Proano

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