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91.
Current glacier recession under the global warming has aroused world-wide attention.Initiated from 1958,the observations show that over the past 50 years,the glacier has changed remarkably in the aspects of snow-firn stratigraphy,ice formation zone,ice temperature,area and terminus position,etc.These changes are apparently the results of temperature rise in this area.The glacier recession continued throughout the entire observed time period,and showed an accelerated tendency since 1985.Meltwater runoff also increased 84.2% over the last 20 years.  相似文献   
92.
Similar to most mountain glaciers in the world, Urumqi Glacier No. 1 (UG1), the best observed glacier in China with continued glaciological and climatological monitoring records of longer than 50 years has experienced an accelerated recession during the past several decades. The purpose of this study is to investigate the acceleration of recession. By taking UG1 as an example, we analyze the generic mechanisms of acceleration of shrinkage of continental mountain glaciers. The results indicate that the accel...  相似文献   
93.
This article, based on the field work took place on the zone of Tuomuer (托木尔) Peak, western Tian Shan (天山) during the period May 2008 to September 2009, obtained the spatial distribution of debris layer on the reference glaciers (Glacier No. 72, Glacier No. 74, Tuomuer Glacier) by detailed measurements of debris thickness and ablation rates on glacier and further by Spot-5 (5 m, 2005) high-resolution satellitic image applying remote sensing and geographic information systems approach to research the spatial...  相似文献   
94.
中国天山冰川生态服务功能及价值评估   总被引:4,自引:1,他引:3  
山岳冰川是干旱区生态环境和社会经济可持续发展的物质基础和特色文化基础,具有独特且无法替代的生态服务功能,而目前对冰川调节生态环境和提供人类福祉等方面服务功能和价值估算研究很少。本文基于第一、二次冰川编目数据,分析中国天山冰川面积和冰储量变化特征;梳理并构建山岳冰川生态服务功能体系,结合单位面积服务功能价格法和当量因子法,评估中国天山冰川年生态服务价值。结果显示:① 1970-2010年间,中国天山冰川面积减少1274 km2,退缩了13.9%,年平均冰川储量减少约4.08×109 m3。高海拔区(> 5200 m)冰川面积出现增加,可能是由于该区域降水增加对冰川积累的作用大于气温上升对冰川消融作用造成的。② 中国天山冰川年生态服务价值为602亿元,气候调节、水文调节和淡水资源供给价值分别占总价值的66.4%、21.6%和9.3%,水力发电的年均生态服务价值约为3.5亿元,其他类型的调节和服务功能价值约12.8亿元。③ 比较分析冰川、森林、草地和湿地生态系统不同服务价值所占总价值比例发现,淡水资源供给/实物生产和生态调节功能在生态系统中均占比例较大,冰川单位面积生态服务价值高于其他类生态系统。本文以期能提高冰川对人类福祉和维持生态环境等方面的认知,服务于冰冻圈生态安全、环境保护以及资源的可持续利用规划与管理。  相似文献   
95.
Journal of Earth System Science - Many of the river basins in northwest China receive water from melting glaciers and snow in addition to groundwater. This region has experienced a significant...  相似文献   
96.
Hydrological processes were compared,with and without the influence of precipitation on discharge,to identify the differences between glacierized and non-glacierized catchments in the Urumqi River source region,on the northern slope of the eastern Tianshan Mountains,during the melting season(May-September) in 2011.The study was based on hydrological data observed at 10-min intervals,meteorological data observed at 15-min intervals,and glacier melting and snow observations from the Empty Cirque,Zongkong,and Urumqi Glacier No.1 gauging stations.The results indicated that the discharge differed markedly among the three gauging stations.The daily discharge was more than the nightly discharge at the Glacier No.1 gauging station,which contrasted with the patterns observed at the Zongkong and Empty Cirque gauging stations.There was a clear daily variation in the discharge at the three gauging stations,with differences in the magnitude and duration of the peak discharge.When precipitation was not considered,the time-lags between the maximum discharge and the highest temperature were 1-3 h,10-16 h,and 5-11 h at the Glacier No.1,Empty Cirque,and Zongkong gauging stations,respectively.When precipitation was taken into consideration,the corresponding time-lags were 0-1 h,13 h,and 6-7 h,respectively.Therefore,the duration from the generation of discharge to confluence was the shortest in the glacierized catchment and the longest in the catchment where was mainly covered by snow.It was also shown that the hydrological process from the generation of discharge to confluence shortened when precipitation was considered.The factors influencing changes in the discharge among the three gauging stations were different.For Glacier No.1 station,the discharge was mainly controlled by heat conditions in the glacierized region,and the discharge displayed an accelerated growth when the temperature exceeded 5℃ in the melt season.It was found that the englacial and subglacial drainage channel of Glacier No.1 had become simpler during the past 20 years.Its weaker retardance and storage of glacier melting water resulted in rapid discharge confluence.It was also shown that the discharge curve and the time-lag between the maximum discharge and the highest temperature could be used to reveal the evolution of the drainage system and the process of glacier and snow melting at different levels of glacier coverage.  相似文献   
97.
Snow samples collected from a 50 m firn core and two snow pits along the route of the 1996/1997 Chinese First Antarctic Inland Traverse Expedition in Princess Elizabeth Land, East Antarctica, have been analyzed for chemical composition and oxygen isotope ratio. Analyzing the relationship between the concentration and flux of major ions and accumulation rate can draw the following conclusions. 1 ) The concentrations of major ions in the atmosphere in the study region is big enough so that the concentrations of the ions do not vary with snow accumulation rate, that is to say, the concentrations of major chemical species are independent of snow accumulation rate. 2) The results of analyzing the depositional styles of major chemical species suggest that wet deposition dominates the major ions flux. In addition, there is no apparent correlation between nssSO2-4 fluctuations and isotope profile. This would indicate the short-term climatic effect of volcanism is not evident in the region.  相似文献   
98.
额尔齐斯河源春季水化学及稳定同位素特征研究   总被引:2,自引:0,他引:2  
基于2018年4月额尔齐斯河源至富蕴段的河水样品, 综合运用Gibbs图、 Piper三线图、 相关矩阵分析等方法对河水中主要的化学离子、 pH值、 电导率、 TDS和氢、 氧稳定同位素等物理化学指标进行了分析。结果表明: 额尔齐斯河源春季河水呈弱碱性, TDS平均值为72.02 mg·L-1, 整体属于低矿化度水。河水中主要离子浓度序列为HCO3- > SO42- > Ca2+ > Na+ > Cl- > NO3- > Mg2+ > K+, 其中HCO3-、 SO42-和Ca2+是最主要的阴阳离子。水化学类型从库依尔特河的HCO3--Ca2+型转变为额尔齐斯河富蕴段的(HCO3-, SO42-)-Ca2+型。从源区至富蕴段各离子含量整体呈增大趋势, 但其增加过程受到复杂因素的影响而出现差异。河水离子主要受水-岩风化作用控制, 且以碳酸盐岩(石灰岩、 白云岩)为主的风化水解是离子的主要来源, 其次是长石类矿物的风化, 还包括下游人类活动的离子输入等。δD和δ18O沿程逐渐增大, 在下游出现了富集现象。  相似文献   
99.
以30个GPS基准站坐标序列为对象,提出分别采用赤池信息量准则(AIC)与贝叶斯信息准则(BIC)噪声模型估计准则判定GPS时间序列噪声特性,对比分析GPS时间序列噪声模型特性,探讨不同噪声模型对GPS站速度及其不确定度的影响.结果表明GPS站坐标序列噪声模型主要表现为FN+WN、PL及FN+RW+WN噪声模型特性;FN+WN噪声模型对GPS站速度估计值的影响相对较小,但在U分量影响最为明显;此外,RW对站速度不确定度的影响不可忽略,正确获取模型参数估计的实际不确定度及改正噪声分量对于合理应用GPS坐标时间序列数据具有重要的意义.  相似文献   
100.
水合碱式硫酸镁晶须材料的水热合成   总被引:10,自引:5,他引:10       下载免费PDF全文
本文研究了水合碱式硫酸镁MgSO4·5Mg(OH)2·3H2O(以下称MOS)晶须的水热合成。良好的晶须可通过MgSO4·7H2O和Mg(OH)2间的水热反应生成。文中研究了各种合成条件对合成过程和产物品质的影响。当反应体系在温度为130℃~170℃、压力为304.0~810.4kPa的条件下,合成出的晶须具有很高的纯度,产率达90%以上,纤维长可达200μm,纤维直径为0.8~1.2μm。  相似文献   
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