Dry valleys

Fountain, A.G., Nylen, T., MacClune, K.L., Dana, G.L. 2006. Glacier mass balances (1993-2001), Taylor Valley, McMurdo Dry Valleys, Antarctica. Journal of Glaciology, 52, 451-462. 

Lancaster, N. 2002. Flux of aeolian sediment in the McMurdo Dry Valleys, Antarctica a preliminary assessment. Arctic, Antarctic, and Alpine Research, 34, 318-323. 

Marchant D.R., Denton G.H., Swisher C.C. Potter N. 1996. Late Cenozoic Antarctic paleoclimate reconstructed from volcanic ashes in the dry valleys region of southern Victoria Land Geological Society of America Bulletin, 108, 181-194. 

Nylen, T.H., Fountain, A.G., Doran, P.T. 2004. Climatology of katabatic winds in the McMurdo dry valleys, southern Victoria Land, Antarctica, Journal of Geophysical Research, 109, 9. 

Witherow R.A., Lyons W.B., Bertler N.A.N., Welch K.A., Mayewski P.A., Sneed S.B., Nylen T., Handley M.J., Fountain A.G. 2006. The aeolian flux of calcium, chloride, and nitrate to the McMurdo Dry Valleys landscape evidence from snow pit analysis. Antarctic Science, 18, 497-505. 

In 2007, 144 million cubic meters of water was used in Switzerland to irrigate around 43,000 hectares on a regular basis and 12,000 hectares on an occasional basis, with the inner-alpine dry valley of the Valais accounting for more than half of the irrigated surface area [9]. The water used for this purpose is taken primarily from water courses, particularly during dry seasons or climate periods, and used directly without any interim storage. 

FIGURE 3 Depth profiles for 14C age and sulfur-to-carbon (S/C) ratios for fulvic acid samples isolated from Lake Fryxell, a permanently ice-covered lake in the McMurdo Dry Valleys, Antarctica (from Aiken et al., 1996). In the upper water column, the fulvic acids have a modern signal. This young fulvic acid derives from perennial algal mats in glacial meltwater streams. At depth, the fulvic acids are quite old (about 3000 years) and are possibly derived from organic material in sediments. The ratio of S/C increases with depth as conditions in the water column become anoxic. 

This paper was supported by the McMurdo Dry Valleys LTER project (OPP98-15512) and a NSF Post-Doctoral Fellowship in Microbial Biology... 

Voytek, M. A., B. B. Ward, and J. C. Priscu. 1998. The abundance of ammonium-oxidizing bacteria in Lake Bonney, Antarctica determined by immunofluorescence, PCR and in situ hybridization. In Ecosystem Dynamics in a Polar Desert. The McMurdo Dry Valleys, Antarctica (J. C. Priscu, Ed.), pp. 217—228. Am. Geophys. Union, Washington, DC. 

Examples of especially dry environments on Earth include the Atacama Desert of northern Chile and the Dry Valleys of Antarctica. Dose et al. (2001) exposed spores, conidia, and cells of several microbes to 15 months of desiccation in the dark at two locations of the Atacama Desert. Bacillus subtilis (bacteria) spores (survival 15%) and Aspergillus niger (fungi) conidia (survival 30%) outlived other species. Deinococcus radiodurans (bacteria) did not survive the desert exposure because they were readily killed at RH between 40% and 80%, which occurred during desert nights (Dose et al. 2001). 

Lyons WB, Welch KA, Snyder G, Olesik J, Graham EY, Marion CM, Poreda RJ (2005) Halogen geochemistry of the McMurdo Dry Valleys, Antarctica Clues to the origin of solutes and lake evolution. Geochim Cosmochim... 

Schafer, J. M., Ivy-Ochs, S., Wieler, R., Leya, I., Baur, H., Denton, G. H., Schliichter, C. (1999) Cosmogenic noble gas smdies in the oldest landscape on earth Surface exposure ages of the Dry Valleys, Antarctica. Earth Planet. Sci. Lett., 167, 215-26. 

There now exist numerous observations of mass-independent isotopic compositions in nature. Most of these have recently been reviewed and will not be repeated here. When the first laboratory measurements of the mass-independent isotope effect were reported by Thiemens and Heidenreich (1983), their occurrence in nature was not expected, except possibly for the early solar system to produce the observed meteoritic CAI data. It is significant to note that, at present, all oxygen-bearing molecules in the atmosphere (except water) possess mass-independent isotopic compositions. These molecules include O2, O3, CO2, CO, N2O, H2O2, and aerosol nitrate and sulfate. Mass-independent sulfur isotopic compositions are also observed in aerosol (solid) sulfates and nitrates and sulfide and sulfate minerals from the Precambrian, Miocene volcanic sulfates, Antarctica dry valley sulfates, Namibian Gypretes, and Chilean nitrates. In addition, martian (SNC meteorites) carbonates and sulfates possess both mass-independent sulfur and oxygen isotopic compositions. These studies have been reviewed recently (Thiemens et al., 2001 Thiemens, 1999). 

Bao et al. (2000b) extracted sulfate from vertical profiles of Antarctic dry valley samples and utilized the oxygen isotopic composition to investigate sources. The variance in the mass-independent oxygen isotopic composition was defined as the source of the anomalous sulfate composition and source. In particular, the source. 

Bao H., Campbell D. A., Bockheim J. G., and Theimens M. H. (2000a) Origins of sulphate in Antarctic dry-valley soils as deduced fro anomalous compositions. Nature 407, 499-502. 

Maurice P. A., McKnight D. M., Leif L., Fulghum J. E., and Gooseif M. (2002) Direct observations of aluminosilicate weathering in the hyporheic zone of an Antarctic dry valley stream. Geochim. Cosmochim. Acta 66, 1335-1347. 

The discovery of the anomalous oxygen isotopic compositions of atmospheric sulfate provides a new means for identifying sulfate of atmospheric origin. Rainwater and aerosols from southern California were found to have A O values in the range of 0%o to -K.5%o (Lee et al., 2001). The average A O of snow sulfate in the Rocky Mountains (Colorado, USA) was - -1.3%o. Sulfate in ice cores, massive sulfate deposits, and Dry Valley soils from various locations also have MIF (Bao et al., 2000 Lee et al., 2001). There appears to be seasonality in the A O of sulfate in precipitation, with higher values in the winter and lower values in the summer, probably due to seasonal changes in climatic elfects that favor aqueous phase S(IV) oxidation in winter relative to summer (Lee and Thiemens, 2001). 

Origins of sulphate in Antarctic dry-valley soils as deduced from anomalous compositions. Nature 407, 499-502. 

Torii T., Yamagata N., Ossaka J., and Murata S. (1979) A view of the formation of saline waters in the dry valleys. Special Issue 13 (ed. T. Nagata). Mem. Natl. Inst. Polar Res. Japan, pp. 22-33. 

Lyons W. B., Welch K. A., and Sharma P. (1998) Chlorine-36 in the waters of McMurdo Dry valley lakes, southern Victoria land Antartica revisited. Geochim. Cosmochim. Acta 62, 185-192. 

If the fault movement is horizontal, such as on the San Andreas fault, the grinding up of the rock in the vicinity of the fault may make it susceptible to weathering and erosion. This can result in long, linear valleys such as those in much of southern California. These valleys, if filled with water, become sag ponds, such as the San Andreas Lake. Dry valley floors are often among the flattest terrain, making them prime locations for building municipal facilities. As the reason for their existence has become understood, however, the wisdom of such construction has been called into question. 

Friedmann, I. and Ocampo, R., 1976. Endolithic blue-green algae in the Dry Valleys Primary producers in the Antarctic desert ecosystem. Science 193 1247—1249. 

Shrestha, B.B. and Jha, P.K. (2009). Habitat range of two alpine medicinal plants in a trans-Himalayan dry valley, central Nepal. Journal of Mountain Science, 6 66-77. 

Scientific activities Collection of birds, seals Meteorites Victoria Land dry valleys... 

Ringrose, S., Kampunzu, A.B., Vink, B.W., Matheson, W. Downey, W.S. (2002) Origin and palaeo-environments of calcareous sediments in the Moshaweng dry valley, southeast Botswana. Earth Surface Processes and Landforms 27, 591-611. 

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