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Changes in physical features of Glacier No. 1 of the Tianshan Mountains in response to climate change
XiangYing Li,YongJian Ding,BaiSheng Ye,TianDing Han
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4621-x
Abstract: This study analyzes the changes in glacier zones and snow composition of Glacier No. 1 in the Tianshan Mountains of China since 1961, and their possible relations with climate. It is found that precipitation dominated the snow composition and that air temperature and precipitation controlled the distribution of glacier zones, but interannual change in precipitation had a relatively large effect on glacier zones and snow composition during 1963–1981 (P10) and 1963–1989 (P11). However, during 1982–2007 (P20) and 1990–2007 (P21), the air temperature rise (0.57°C/10 a for P20, 0.76°C/10 a for P21) was more influential than the precipitation increase (51.3 mm/10 a for P20), and air temperature was principally responsible for the evolution of glacier zones and snow composition most probably resulting from recent climate warming.
Synthesis of secondary compounds as a uv-screening strategy of lichenized fungi from the tropical andes and its possible role on the early earth
Marcano,Vicente; Balza,Alirio; Pérez,Roxana; Rojas,José Alberto; Díaz,Ricardo; Palacios,Ernesto;
Ernstia , 2010,
Abstract: photochemical analysis of secondary compounds in lichens from the venezuelan andean snow and glacier zones (4800-5000 m) was carried out in order to determine the absorbance capacity of uv radiation in the uva, uvb and uvc ranges, and to characterize the probable uv-protective function. spectrotometric (uv-vis, nir, ftir, ms, nmr) and chromatographic (hptlc) standardized techniques were utilized to identify the lichen compounds. uvb radiation in the glacier zone (5000 m) revealed a value of ~ 3 w m-2 which is sufficient to produce important biochemical and cell alterations. of a total of 25 lichen species distributed in the glacier and snow zones, 68% showed the presence of phenolic compounds having strong absorption for uvc radiation, 96% had strong absorption for uvb radiation and 100% had strong absorption for uva radiation. the substance groups that had the highest resistance to uva and uvb radiation were characterized by ester bonds among both phenolic units (depsides). they were the most abundant products to be found among the lichens, whereas substances having ester and ether bonds in both phenolic units (depsidones) had a higher capacity to absorb uvc radiation. microorganisms having adaptive uv-screening responses similar to the lichens investigated are expected to occur on the early earth in o2 levels ≤ 10-2.
Glacier Mass-Balance Variation in China during the Past Half Century  [PDF]
Yousif Elnour Yagoub, Zhongqin Li, Ahmed A. H. Siddig, Omer Said Musa, Muhammad Naveed Anjum
Journal of Geoscience and Environment Protection (GEP) , 2018, DOI: 10.4236/gep.2018.65004
Abstract:
The aim of this study is to investigate the impact of temperature trend on glacier-mass balance, snow density, snowmelt, snow depth and runoff by using observations of nine glacier stations that covered most of the China over the period of 1979-2013. Trend analysis showed an increasing trend of temperature on all of the selected stations. On an average, temperature was increasing at the rate of 0.46/10a. The increasing trend of temperature showed a negative relationship with annual glacier-mass balance on most of the stations and caused a decrease in annual balance. Results of Pearson’s correlation analysis showed a highly significant negative correlation between temperature and snow density (correlation coefficient (CC = -0.661 at 0.01 significance level). There was a significant positive correlation between temperature and snowmelt (CC = 0.532 at 0.01 significance level). There was a significant negative correlation between temperature and snow depth (correlation coefficient (CC = -0.342 at 0.05 significance level). Moreover, there was a significant positive correlation between temperature and runoff (CC = 0.586 at 0.01 significance level). Increasing trend of temperature caused an increasing trend of annual snowmelt and runoff anomaly% at the rate of 24.82/10a and 9.87/10a, respectively. On the other hand, a declining trend in annual snow density and snow depth anomaly% was found at a rate of -5.32/10a and -1.93/10a, respectively. We concluded that the snow density, snowmelt and runoff are significantly sensitive to temperature in China. This contribution has provided information for further understanding of glacier variation and its influencing factors.
Synthesis of secondary compounds as a uv-screening strategy of lichenized fungi from the tropical andes and its possible role on the early earth Síntesis de compuestos secundarios como una estrategia de pantalla contra radiación ultravioleta en hongos liquenizados de los andes tropicales y su posible rol en la edad temprana de la tierra
Vicente Marcano,Alirio Balza,Roxana Pérez,José Alberto Rojas
Ernstia , 2010,
Abstract: Photochemical analysis of secondary compounds in lichens from the Venezuelan Andean snow and glacier zones (4800-5000 m) was carried out in order to determine the absorbance capacity of UV radiation in the UVA, UVB and UVC ranges, and to characterize the probable UV-protective function. Spectrotometric (UV-VIS, NIR, FTIR, MS, NMR) and chromatographic (HPTLC) standardized techniques were utilized to identify the lichen compounds. UVB radiation in the glacier zone (5000 m) revealed a value of ~ 3 W m-2 which is sufficient to produce important biochemical and cell alterations. Of a total of 25 lichen species distributed in the glacier and snow zones, 68% showed the presence of phenolic compounds having strong absorption for UVC radiation, 96% had strong absorption for UVB radiation and 100% had strong absorption for UVA radiation. The substance groups that had the highest resistance to UVA and UVB radiation were characterized by ester bonds among both phenolic units (depsides). They were the most abundant products to be found among the lichens, whereas substances having ester and ether bonds in both phenolic units (depsidones) had a higher capacity to absorb UVC radiation. Microorganisms having adaptive UV-screening responses similar to the lichens investigated are expected to occur on the early Earth in O2 levels ≤ 10-2. Se realizó un análisis fotoquímico de compuestos secundarios presentes en líquenes procedentes de las zonas nival y glaciar de los Andes Venezolanos con la finalidad de determinar la capacidad de absorbancia de radiación UV en los rangos UVA, UVB y UVC y caracterizar de esta manera la probable función UV-protectora. Técnicas normalizadas espectrométricas (UV-VIS, NIR, FTIR, MS, NMR) y cromatográficas (HPTLC) se utilizaron para identificar los compuesto liquénicos. La UVB radiación en la zona glaciar (5000 m) mostró un valor de ~ 3 W m-2 lo cual es suficiente para producir importantes alteraciones celulares y bioquímicas. De un total de 25 especies de líquenes distribuidas en las zonas nival y glaciar, el 68% reveló la presencia de compuestos fenólicos presentando una fuerte absorción para la radiación UVC; un 96% presentó una fuerte absorción para la radiación UVB, mientras el 100% mostró una fuerte absorción para la radiación UVA. Los grupos de sustancias que presentaron la más alta resistencia para las radiaciones UVA y UVB estuvieron caracterizados por enlaces ester entre ambas unidades fenólicas (dépsidos). Estos productos fueron los más abundantes hallados en los líquenes, mientras sustancias presentando enlaces ester y éter entre am
Change Monitoring of Gangotri Glacier using Remote Sensing
M Anul Haq,Kamal Jain,KPR Menon
International Journal of Soft Computing & Engineering , 2012,
Abstract: Himalayas has one of the largest resources of snow and ice, which act as a freshwater reservoir for all the rivers originating from it. Monitoring of these resources is important for the assessment of availability of water in the Himalayan Rivers. The mapping of Glaciers is very difficult task because of the inaccessibility and remoteness of the terrain. Remote sensing techniques are often the only way to analyze glaciers in remote mountains and to monitor a large number of glaciers in multitemporal manner. This paper presents the results obtained from the analysis of a set of multitemporal Landsat MSS, TM and ETM+ images for the monitoring and analysis of Gangotri Glacier main trunk change. The investigation has shown an overall reduction in glacier area from 63.227 sq km to 62.412 sq km between 1972 and 2010, an overall deglaciation of 1.3% percent. To monitor seasonal snow cover, NDSI based algorithm was used to monitor the Gangotri glacier main trunk
Determination of a typical snow load
Androi？, Boris,Dujmovi？, Darko,D？eba, Ivica,Gaji？-？apka, Marjana,Zaninovi？, Ksenija
- , 2001,
Abstract: Sa？etak The study of snow regimen characteristics, conducted in accordance with the European standard for snow load ENV 1991-2-3:1995 and in keeping with meteorological practice, is described. Typical snow load, i.e. load that can be expected once in 50 years, was defined on the basis of information on the water content in snow and on the height of snow cover. Four snow-related climatic zones in Croatia were determined based on analyses of changes registered at various altitudes
Geochemical characteristics and zones of surface snow on east Antarctic Ice Sheet
Jiancheng Kang,Leibao Liu,Dahe Qin,Dali Wang,Jiahong Wen,Dejun Tan,Zhongqin Li,Jun Li,Xiaowei Zhang
Chinese Science Bulletin , 2004, DOI: 10.1007/BF03185789
Abstract: The surface-snow geochemical characteristics are discussed on the East Antarctic Ice Sheet, depending on the stable isotopes ratios of oxygen and hydrogen, concentration of impurities (soluble-ions and insoluble micro-particle) in surface snow collected on the ice sheet. The purpose is to study geochemical zones on the East Antarctic Ice Sheet and to research sources and transportation route of the water vapor and the impurities in surface snow. It has been found that the ratio coefficients, as S1, d1 in the equation δD =S 1δ18O +d 1, are changed near the elevation 2000 m on the ice sheet. The weight ratio of C1 /Na+ at the area below the elevation of 2000 m is close to the ratio in the sea salt; but it is about 2 times that of the sea salt, at the inland area up to the elevation of 2000 m. The concentrations of non-sea-salt Ca2+ ion (nssCa2+) and fine-particle increase at the interior up to the elevation 2000 m. At the region below the elevation of 2000 m, the impurity concentration is decreasing with the elevation increasing. Near coastal region, the surface snow has a high concentration of impurity, where the elevation is below 800 m. Combining the translating processes of water-vapor and impurities, it suggests that the region up to the elevation 2000 m is affected by large-scale circulation with longitude-direction, and that water-vapor and impurities in surface snow come from long sources. The region below the elevation 2000 m is affected by some strong cyclones acting at peripheral region of the ice sheet, and the sources of water and impurities could be at high latitude sea and coast. The area below elevation 800 m is affected by local coastal cyclones.
Discovery of Quaternary glacial evidence of Snow Mountain in Taiwan, China
Zhijiu Cui,Jianfu Yang,Gengnian Liu,Xin Wang,Guocheng Song
Chinese Science Bulletin , 2000, DOI: 10.1007/BF02887108
Abstract: There are glacial remains of three different periods on the main peak of Snow Mountain in Taiwan province, including cirque lake, crosswall, polished surface, striation, moraine etc. These three different periods were called, respectively, Shanzhuang ((44.25 ±3.72) kaBP), Shuiyuan ((18.26 ±1.52) kaBP), and Xueshan glacial stages (the late period of last glaciation). It is characterized by the earlier glacier broad in scale.
Initial estimate of the contribution of cryospheric change in China to sea level rise
JiaWen Ren,BaiSheng Ye,YongJian Ding,ShiYin Liu
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4474-3
Abstract: Recent studies have shown that cryospheric melting is becoming the dominant factor responsible for sea level rise, and that the melt-water from mountain glaciers and ice caps has comprised the majority of the cryospheric contribution since 2003. Analysis of the estimations of cryospheric melt-water and precipitation in glacier regions indicated that the potential contribution of the cryosphere in China is 0.14 to 0.16 mm a 1, of which approximately 0.12 mm a 1 is from glaciers. The contribution of glaciers in the outflow river basins is about 0.07 mm a 1, accounting for 6.4% of the total from global glaciers and ice caps.
Methods for extraction of microorganism DNA from glacier surface snow
PeiYing Yan,ShuGui Hou,Tuo Chen,ShuHong Zhang,WeiJun Sun,
寒旱区科学 , 2012,
Abstract: In order to thoroughly investigate the diversity of glacier microorganisms, four DNA extraction methods with different lysis patterns were tested and two screened methods (the Bosshard-Bano method and the Zhou method) were optimized for the most effective form of the filter membrane (cut vs. uncut), the DNA extraction method, and the precipitation method. The two optimized methods were then compared with the commercial Mo-Bio DNA extraction kit, and the results showed that the kit was generally suitable for extraction of microorganism DNA from glacier surface snow. Procedurally, it was found that a modified Bosshard- Bano method (i.e., cutting the filter membrane into pieces, using a specific lysis pattern lysozyme (5 mg/mL)-protease K (1 mg/mL)-CTAB (1%)-SDS (1%)], performing the extraction only once by chloroform-isoamyl alcohol (24:1), and conducting DNA precipitation by pure ethanol) was also an effective and less expensive method for extraction of microorganism DNA from glacier surface snow.
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