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Xiangying Li Yongjian Ding Tianding Han Shichang Kang Zhongbo Yu Zhefan Jing 《水文研究》2019,33(26):3258-3281
Temporal variation of runoff chemistry and its seasonal controls relating to chemical weathering processes and drainage system evolution were examined at Urumqi Glacier No.1 in Xinjiang, China, over a full melt season. The dominant ions in meltwater runoff are HCO3?, Ca2+, and SO42?; and Fe, Sr, and Al are dominant elements. Concentrations of major ions and some elements show periodic variations with seasons and negatively correlate with discharge, whereas other elements (e.g., Al, Ni, Cu, Zn, Cd, and Pb) show a random change, providing insights into the hydrological and physicochemical controls. HCO3? and Ca2+ are primarily derived from calcite, SO42? and Fe mainly come from pyrite, and Sr and Al principally originate from silicate. Hydrochemical fluxes of solutes exhibit strong seasonality but are positively related to discharge, suggesting an increasing release of solutes during higher flow conditions. Solute yields, cation denudation rate, and chemical weathering intensity observed at Urumqi Glacier No.1 are higher than those at most basins worldwide. This suggests that chemical weathering in central Asia may be stronger than at other glacial basins with similar specific discharge. Concentrations of some elements (e.g., Fe, Al, As, Pb, and Zn) are close to or exceed the guidelines for drinking water standards in meltwater‐fed rivers. These rivers may face future challenges of water quality degradation, and relationships between changing flow and water quality conditions should be established soon, given that development of channelized flow is expected to be earlier over a melt season in a warming climate. 相似文献
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采用玉龙雪山白水1号冰川2011年6~9月的高精度GPS实测数据,对白水1号冰川的运动速度进行了探索性研究,并与其他数条典型冰川作了对比分析。结果表明,与北半球典型大陆性冰川相比,玉龙雪山白水1号冰川运动速度明显偏快,介于2.34~4.74 m/月之间,是同规模大陆性冰川的月运动速度的6~10倍,有独特的海洋性冰川运动特征。与藏东南同一类型的帕隆94冰川相比,玉龙雪山白水1号冰川运动速度约为其一半,这说明海洋性冰川的运动速度与规模成正比。同时,白水1号冰川末端平均海拔为4 381 m,近10年几乎保持了相同的退缩速度,说明在当今气候变化背景下,白水1号冰川对气候变暖的响应程度相同。 相似文献
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选择胶东玲珑金矿典型矿体47号脉为研究对象,应用基岩地球化学方法,测试微量元素含量,研究微量元素与金的相关关系、计算微量元素的浓集系数并确定其轴向分带,探讨微量元素对深部金成矿的指示意义,期待能对玲珑金矿深部找矿提供一些参考.初步认识如下:矿区金矿体的最佳指示元素依次为Au、Ag、Bi、As、Cu、Co、Mo、Sb;金矿体的轴向分带序列从上到下依次为As、Pb、Ag、Cu、Hg、Sb、Mo、Ni、Th、V、U、Mn、Zn、Bi、Co、Au;矿体中Au、Bi、Ag、As富集系数大,Cu、Co富集系数中等,而Zn在矿体中相对亏损.研究结果表明,在深部47号矿体仍有较好的成矿前景. 相似文献
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This paper is based on observed mass balance between East and West Branch of Urumqi Glacier No. 1, meteorological data during 1988-2010, comparative studies the mass balance variations, and analyses the mass balance sensitivity to climate change. Results show that average mass balance of East and West Branch was 532 mm/a and 435 mm/a, cumulative mass balance was 12,227 mm (ice thinned by 13.6 m) and 10,001 mm (ice thinned by 11.1 m), respectively, and mass loss of East Branch was 97 mm/a larger than West Branch. The East and West Branch ELA (equilibrium line altitude) ascended about 176 m and 154 m, analysis shows the steady-state ELA0 was 3,942 m a.s.l. and 4,011 m a.s.l., and when East and West Branch mass balance decreased by 100 mm, ELA ascended 20 m and 23 m, respectively. The AAR (accumulation area ratio) of East and West Branch presented an obviously decreasing trend of 34.5% and 23%, equilibrium-state AAR0 was 65% and 66%, when East and West Branch mass balance increased by 100 mm, AAR ascended 4.6% and 4.2%, respectively. Glacier mass balance was sensitive to change of net ablation, net ablation of East and West Branch increased 10×104 m3 , and mass balance decreased 110 mm and 214 mm, respectively. By analyzing mass balance sensitivity to climate change, results suggest that East and West Branch mass balance decreased (increased) 463 mm and 388 mm when ablation period temperature increased (decreased) by 1°C, East and West Branch mass balance increased (decreased) 140 mm and 158 mm when annual precipitation increased (decreased) by 100 mm, and sensitivity of East Branch mass balance to climate change was more intense than that of West Branch. 相似文献
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In July, 2009, we investigated the Ningchan River Glacier No. 3. A control network was established around the glacier and the expedition used a GPS-RTK to measure glacial area, terminal and surface altitude, and used an EKKO GPR to measure glacier thickness. We used a topographic map based on 1972 aerial photo, two TM images in 1995, 2009, and GPS-RTK data in 2009, to analyze the change of the Ningchan River Glacier No. 3 since 1972. Through analysis we found this glacier has been seriously shrinking over the past 37 years. The glacier terminal retreated about 6%, the area was reduced about 13.1%, the volume was reduced about 35.3%, and glacier shrinkage is mainly in the form of thinning. Glacier average thickness reduced from 36.8 m in 1972, to 27.4 m in 2009. Meteorological data around the study area shows that this region in recent decades has undergone differential warming which is the main reason for rapid glacier shrinkage. 相似文献
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