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Journal of Mountain Science 2015年第2期12卷 298-312页

作者： LU Heng WEI Wen-shou LIU Mingzhe HAN Xi HONG Wen Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Desert Meteorology China Meteorological Administration tianshan station for snow & avalanche research

In this study, meteorological factors and snowmelt rate at an open site on sunny slope(OPS) and beneath forest canopy openness on shady slope(BFC) were measured using an automatic weather station and snow lysimeter during the snowmelt period in 2009, 2010 and 2013. The energy budget over snow surface was calculated according to these meteorological datasets. The analysis results indicated that the net shortwave radiation(K) and sensible heat flux(H) were energy sources, and the latent heat flux(LVE) was energy sinks of snow surfaces at all sites. The net longwave radiation(L) was energy sink at OPS and 80% BFC, but energy source at 20% BFC. The gain of K, H, and the loss of LVE at BFC were obviously lower than those at OPS. The L was the maximum difference of energy budget between snow surface at BFC and OPS. In warm and wet years, the most important factor of the energy budget variation at OPS was air humidity and the second mostimportant factor was air temperature. However, the ground surface temperature on the sunny slope was the most important factor for L and energy budget at BFC. With the increases in forest canopy openness and the slope of adjacent terrains, the influences of ground surface temperature on the sunny slope on L and the energy budget over snow surface at BFC increased, especially when the snow cover on the sunny slope melts completely.

关键词： Energy budget Seasonal snow snowmelt period tianshan Mountains

Observations and Modeling of Incoming Longwave Radiation to snow Beneath Forest Canopies in the West tianshan Mountains, China

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Journal of Mountain Science 2014年第5期11卷 1138-1153页

作者： LU Heng WEI Wen-shou LIU Ming-zhe HAN Xi HONG Wen Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences Institute of Desert Meteorology China Meteorological Administration tianshan station for snow & avalanche research

Forest canopy reduces shortwave radiation and increases the incoming longwave radiation to snowpacks beneath forest canopies. Furthermore, the effect of forest canopy may be changed by complex topography. In this paper, we measured and simulated the incoming longwave radiation to snow beneath forest at different canopy openness in the west tianshan Mountains, China(43°16'N, 84°24'E) during spring 2013. A sensitivity study was conducted to explore the way that terrain influenced the incoming longwave radiation to snow beneath forest canopies. In the simulation model, measurement datasets, including air temperature, incoming shortwave radiation above canopy, and longwave radiation enhanced by adjacent terrain, were applied to calculate the incoming longwave radiation to snow beneath forest canopy. The simulation results were consistent with the measurements on hourly scale and daily scale. The effect of longwave radiation enhanced by terrain was important than that of shortwave radiation above forest canopy with different openness except the 20% canopy openness. The longwave radiation enhanced due to adjacent terrain increases with the slope increase and temperature rise. When air temperature(or slope) is relatively low, thelongwave radiation enhanced by adjacent terrain is not sensitive to slope(or air temperature), but the sensitivity increases with the decrease of snow cover area on sunny slope. The effect of longwave radiation is especially sensitive when the snow cover on sunny slope melts completely. The effect of incoming shortwave radiation reflected by adjacent terrain on incoming longwave radiation to snow beneath forest canopies is more slight than that of the enhanced longwave radiation.

关键词： Incoming longwave radiation snow beneath forest canopy Simulation model Complex topography Sensitivity study

Metamorphism and Microstructure of Seasonal snow:Single Layer Tracking in Western tianshan,China

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Journal of Mountain Science 2014年第2期11卷 496-506页

作者： HONG Wen WEI Wen-shou LIU Ming-zhe LU Heng HAN Xi ZHANG Yan-wei Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences Institute of Desert Meteorology China Meteorological Administration tianshan station for snow Cover and avalanche research College of Environment and Planning Shangqiu Normal University

【Title】【Author】snowpack is a combination of several snow layers. Accordingly, snowpack natural metamorphism is composed of several stages. The aim of this study is to investigate the natural snow metamorphism at the snow layer unit. The field investigation was conducted at the tianshan station for snow Cover and avalanche research, Chinese Academy of Sciences （43°16＇ N, 84°24＇ E, and 1,776 m a.s.l.）, during the winter of 2010-2011. A complete metamorphic procedure and the corresponding microstructure of a target snow layer were tracked. The results indicate that： the ideal and complete metamorphic process and the corresponding predominant snow grain shape have 5 stages： 1） unstable kinetic metamorphism near the surface; 2） unstable kinetic metamorphism under pressure; 3） stable kinetic metamorphism; 4） equilibrium metamorphism; 5） wet snow metamorphism. snow grain size sharply decreased in the surface stage, and then changed to continuously increase. Rapid increase of grain size occurred in the stable kinetic metamorphism and wet snow metamorphism stage. The characteristic length was introduced to represent the real sizes of depth hoar crystals. The snow grain circularity ratio had a variation of “rapid increase – slow decrease – slow increase”, and the snow aggregations continuously increased with time. snow density grew stepwise and remained steady from the stable kinetic to the equilibrium metamorphism stage. The differences in metamorphism extent and stages among snow layers, led to the characteristic layered structure of snowpack.

关键词： snow metamorphism snow microstructure Tracking Seasonal snow tianshan

Change in Fresh snow Density in tianshan Mountains,China

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Chinese Geographical Science 2011年第1期21卷 36-47页

作者： CHEN Xia WEI Wenshou LIU Mingzhe Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China tianshan station for snow-cover and avalanche research Chinese Academy of Sciences Urumqi 830011 China

The fresh snow density was observed with snow analyzer (snow Fork) at tianshan station for snowcover and avalanche research, Chinese Academy of Sciences from February 21 to March 5, 2009. Results show that fresh snow density increases from the 5th h to the 291st h after the snowfall, with an average rate of increase of 4.0×10-4 g/(cm3·h) (R2 = 0.943). Analysis shows that fresh snow density is negatively correlated with the compac-tion rate of fresh snow (R2 = -0.960). Inversely, it is positively correlated with fresh snow viscosity (R2 = 0.896). In relation to meteorological factors, ground temperature rising at a depth of 40 cm is the major driving factor of snow density increase. The temperature increase in fresh snow layer and the decrease in depth hoar layer have the most prominent impacts on the snow density increase in the afternoon. Principal component analysis shows that the de-terminant factors of fresh snow density change can be grouped into 3 types as follows: 1) dynamic factor contributes about 69.71% to fresh snow density change, with a significant effect from the 5th h to the 106th h after the snowfall; 2) exogenous energy factor contributes about 20.91% to it, with a significant effect at the 130th h; and c) endoge-nous energy factor contributes about 9.38% to it, with a significant effect at the 130th h and the 195th h.

关键词： fresh snow density compaction rate energy conversion principal component analysis tianshan Mountains China

Variations of snow Temperature and their Influence on snow Cover Physical Parameters in the Western tianshan Mountains,China

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Journal of Mountain Science 2011年第6期8卷 827-837页

作者： CHEN Xia WEI WenShou LIU MingZhe GU GuangQin Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Hebei Key Laboratory for Meteorology and Eco-environmen Shijiazhuang 050021 China HeBei Climate Center Shijiazhuang 050021 China Institute of Desert Meteorology China Meteorological Administration Urumqi 830011 China tianshan station for snow-cover and avalanche research Chinese Academy of Sciences Urumqi 830011 China

This article discussed about snow temperature variations and their impact on snow cover parameters. Automatic temperature recorders were used to sample at lo-minute intervals at the tianshan station for snow-cover and avalanche research, Chinese snow temperature Academy of Sciences. lo-layer and the snow cover parameters were measured by the snow property analyzer （snow Fork） in its Stable period, Interim period and snow melting period. Results indicate that the amplitude of the diurnal fluctuation in the temperature during snow melting period is 1.62 times greater than that during Stable period. Time up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours, and lags behind the peak atmospheric temperature by more than 0.2 hours during all three periods. The optimal fitted function of snow temperature profile becomes more complicated from Stable period to snow melting period. 22 h temperature profiles in Stable period are the optimal fitted by cubic polynomial equation. In Interim period and snow melting period, temperature profiles are optimal fitted by exponential equation between sunset and sunrise, and by Fourier function when solar radiation is strong. The vertical gradient in the snow temperature reaches its maximum value at the snow surface for three periods. The peak of this maximum value occurs during Stableperiod, and is 4.46 times greater than during Interim period. The absolute value of temperature gradient is lower than 0.1℃ cm-1 for 30 cm beneath snow surface. snow temperature and temperature gradient in Stable period-Interim period indirectly cause increase （decrease） of snow density mainly by increasing （decreasing） permittivity. While it dramatically increases its water content to change its permittivity and snow density in snow melting period.

关键词： snow temperature Vertical temperaturegradient Optimal fitting function snow density Western tianshan Mountains China

Chemical Characteristics of snow-Firn Pack in Altai Mountains and Its Environmental Significance

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Journal of Earth Science 2011年第4期22卷 482-489页

作者：王飞腾王林康剑寇福堂 State Key Laboratory of Cryospheric Sciences/tianshan Glaciological station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Kanas National Nature Reserve

In order to study the chemical characteristics of snow-firn pack in Altai Mountains and its environmental significance, a 1.5-m deep snow-firn pack was dug in the accumulation zone （3 300 m a.s.I.） of the Kanas Glacier in August 2009. A total of 15 samples were analyzed for major ions. Results show that the concentrations of major ions in the snow-firn pack are NH4＋〉SO4 2-〉Ca2＋〉NO3＋〉 Na＋〉CI〉K＋〉Mg2＋. NH4＋ is the dominant cation with a medium value of 4.7 ueq-L-1, accounting for 39.8% of the total cations, and SO42- is the dominant anion, with a medium value of 4.0 ueq.L-I, which accounts for 33.9% of the total cations. Compared with Belukha Glacier （Altai）, Urumqi Glacier No. 1, and the Inilchek Glacier （Tienshan）, there is a lower ion concentrations in the Kanas snow-firn pack. Potential sources of these chemical species are explored using correlation and empirical orthogonal function （EOF） analyses. The analyses indicate that major ion concentrations （except NH4＋） originate from crustal dust. Backward trajectory analysis was applied to get the origin of the air mass to Kanas Glacier. The results suggest that air pollutants emitted by forest fires in Siberia could be transported and influence the NH4＋, NO3, and SO42 concentrations on the Kanas Glacier.

关键词： Kanas Glacier snow-firn chemistry Altai Mountains backward trajectory forest fires.

Selected Trace Elements in snowpack on Urumqi Glacier No. 1, Eastern tianshan, China: As Yielded by Leaching Treatment Representative of Real-World Environmental Conditions

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Journal of Earth Science 2011年第4期22卷 449-459页

作者：张明军王圣杰王飞腾李月芳 College of Geography and Environment Sciences Northwest Normal University State Key Laboratory of Cryospheric Sciences/tianshan Glaciological station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

To investigate the seasonal variability and potential environmental significance of trace elements in mountain glaciers, the surface snow and snow pit samples were collected at Urumqi Glacier No. 1 （43°06′N, 86°49′E, 4 130 m a.s.l.）, eastern tianshan （天山）, from September 2002 to September 2003, and analyzed for Li, V, Cr, Mn, Co, Cu, and Ba. The samples were acidified （leached） in a manner intended to reasonably approximate the extent to which the natural hydrologic and weathering cycles would liberate elements from mineral grains （dusts） in the ice and snow into the environment. The mean concentrations of Li, V, Cr, Mn, Co, Cu, and Ba are 0.2, 1.1, 0.8, 14.8, 0.1, 0.7, and 3.2 ng/g in surface snow but 1.0, 2.2, 1.8, 92.4, 0.8, 2.9, and 16.2 ng/g in snow pits, respectively. Input varies seasonally： in general, concentrations in the winter are higher than those in the summer. The trace elements are somewhat enriched （relative to expected abundances in material taken di- rectly from the earth＇s crust） and similar to what is observed in both pre-industrial and modern atmospheric dusts, although some anthropogenic components from nearby industrial cities may be present. Concentration vertical profiles can be redistributed in the post-depositional process, which may cause loss of trace elements in the summer.

关键词： trace element snowpack postdepositional process Urumqi Glacier No. 1.

Comparison of the water consumption levels of four shelterbelt tree species in a typical arid oasis in Northwest China

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 169-176页

作者： Shuai Fu Bingxian Xu Yufang Leng Yuxin Peng Guogen Tao Lanhai Li School of Taxation and Public Administration Jiangxi University of Finance and EconomicsNanchang 330013China research team of International price analysis and prediction of bulk commodities Jiangxi University of Finance and EconomicsNanchang 330013China School of Foreign Languages Jiangxi University of Finance and EconomicsNanchang 330013China Laboratory of Water Cycle and Water Use in Arid Region Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China tianshan snow Cover and avalanche Observation and research station of Xinjiang Xinyuan 835800XinjiangChina

The shelterbelt is an indispensable barrier to the ecological and economic development of an *** moisture,groundwater and irrigation greatly affect the shelterbelt water consumption and *** this study,the transpiration rate of shelterbelt trees,soil moisture and meteorological data were collected to determine the effects of soil moisture and meteorological factors on the water consumption of different shelterbelt tree species via multivariate statistical *** results showed that the water consumption rate was positively correlated with solar radiation,air temperature and ***,the leaf transpiration rate exhibited the trend of *** Jabl.˃***˃*** Carr.>***,while the average daily water consumption decreased in the order of ***>*** Jabl.>*** Carr.>*** average daily water consumption levels of ***,*** Jabl.,*** *** *** were(9.15±0.92)kg/(tree∙d),(6.95±1.41)kg/(tree∙d),(4.43±1.32)kg/(tree∙d),and(1.58±0.18)kg/(tree∙d),*** the growing season,the soil water consumption levels of ***,*** Jabl.,*** Carr.,and *** in each shelterbelt tree stand reached 674.8,336.9,358.1 and 161.7 kg,*** than 96%of the soil moisture lost was provided by the upper 120-cm soil *** the influence and contribution of soil water and meteorological factors to shelterbelt water consumption is beneficial for shelterbelt management and protection.

关键词： water consumption irrigation management shelterbelts soil moisture climatic factors

Fuzzy–frequency ratio model for avalanche susceptibility mapping

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International Journal of Digital Earth 2016年第12期9卷 1168-1184页

作者： Satish Kumar Snehmani Pankaj Kumar Srivastava Akshay Gore Mritunjay Kumar Singh College of Engineering Studies University of Petroleum&Energy Studies(UPES)DehradunUttarakhandIndia snow and avalanche Study Establishment Defence Research&Development Organisation(DRDO)ChandigarhIndia Spatial Strokes Technologies Private Limited ZirakpurPunjabIndia

avalanche activities in the Indian Himalaya cause the majority of fatalities and responsible for heavy damage to the *** susceptibility maps assist decision-makers and planners to execute suitable measures to reduce the avalanche *** the present study,a probabilistic data-driven geospatial fuzzy–frequency ratio(fuzzy–FR)model is proposed and developed for avalanche susceptibility mapping,especially for the large undocumented *** fuzzy–FR model for avalanche susceptibility mapping is initially developed and applied for Lahaul-Spiti *** fuzzy–FR model utilized the six avalanche occurrence factors(***,aspect,curvature,elevation,terrain roughness and vegetation cover)and one referent avalanche inventory map to generate the avalanche susceptibility *** 292 documented avalanche locations from the avalanche inventory map,233(80%)were used for training the model and remaining 59(20%)were used for validation of the *** avalanche susceptibility map is validated by calculating the area under the receiver operating characteristic curve(ROC-AUC)*** validation of the results using ROC-AUC technique,the success rate and prediction rate were *** values of success rate and prediction rate were 94.07%and 91.76%,*** validation of results using ROC-AUC indicated the fuzzy–FR model is appropriate for avalanche susceptibility mapping.

关键词： snow avalanche avalanche susceptibility mapping GIS fuzzy–frequency ratio(fuzzy–FR)model Lahaul&Spiti

Characteristics and Environmental Significance of pH and EC in Summer Rainfall and Shallow Firn Profile at Yulong snow Mountain,Lijiang City,China

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Journal of Earth Science 2010年第2期21卷 157-165页

作者：李宗省何元庆 Wilfred H Theakstone 贾文雄辛惠娟张蔚刘婧王淑新 State Key Laboratory of Cryospheric Sciences Yulong Snow Mountain Glacial and Environmental Observation StationCold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Graduate University of Chinese Academy of Sciences Institute of Environment and Climate Change research in Western China Lanzhou University School of Environment and Development University of Manchester Yulong snow Mountain Glacial and Environmental Observation station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The seasonal and inter-annual variations of pH and EC （electrical conductivity） at Yulong （玉龙） snow Mountain, Lijiang （丽江） City, are sensitive to precipitation variations and are important indicators of the atmospheric environment. The pH of summer rainfall at Lijiang City ranges from 6.7 to 7.4, and alkaline mineral salts dominate the variations of rainfall acidity, pH values in the shallow firn profile at Baishui （白水） Glacier No. 1 range from 5.6 to 6.3, and EC values from 2.4 to 7.3 μs/cm. The ranges are lower than those in other firn cores from China because of stronger elution and the influence of marine aerosols. This indicates that environmental records from a monsoonal temperate glacier differ from those at continental glaciers.

关键词： pH EC Baishui Glacier No. 1 Yulong snow Mountain Lijiang City.