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61.
Hydrochemical characteristics and recharge sources of Lake Nuoertu in the Badain Jaran Desert 总被引:1,自引:0,他引:1
Yue Wu Naiang Wang Liqiang Zhao Zhenyu Zhang Li Chen Ying Lu Xiaonan L Jinlong Chang 《科学通报(英文版)》2014,59(9):886-895
We present a case study of physical and chemical indicators and isotope characteristics of Lake Nuoertu,one of the largest and deepest lakes of the Badain Jaran Desert.We analyze the concentrations of eight ions,total dissolved solids,and stable isotope composition of the lake and groundwater,as well as radioactive isotope tritium concentration in groundwater.The results show that annual and seasonal variations of the physical and chemical characteristics of Lake Nuoertu water are significantly greater than those of groundwater.The lake is uniformly mixed in the horizontal and vertical directions,and the hydrochemical types of the lake at different depths are consistent for Na–Cl–CO3–(SO4).Stable isotope composition of the lake and groundwater at Nuoertu is distributed along the local evaporation line(EL)slope,which is less than the slope of the global meteoric water line.The comparatively small slope shows the characteristic strong evaporation in the study area.Lake water isotopes are mostly in the upper right corner of the EL,whereas groundwater is mostly in the lower left corner.The main recharge source of Nuoertu lake water is groundwater,in combination with lake water and groundwater level change.The age of tufa springs around Nuoertu is about75–80 a,which shows that the initial recharge source of the lake is a mix between modern and 1952 or older;however,further research is required. 相似文献
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64.
甘肃民勤繁殖鸟类群落及演替研究 总被引:3,自引:0,他引:3
1990年夏,在甘肃民勤进行了10个繁殖鸟类群落结构及其演替规律的调查。荒漠环境的鸟类群落常形成单种优势,造成群落的鸟类多样性指数降低。对群落相似性系数进行聚类分析得到的聚类图与群落演替过程基本吻合,表明相衔接的演替阶段的群落相似性程度较高。 相似文献
65.
Reconstruction of precipitation in the last 140 years from tree ring at south margin of the Tengger Desert, China 总被引:7,自引:0,他引:7
GAO Shangyu LU Ruijie QIANG Mingrui HASI Eerdun ZHANG Dengshan CHEN Yuan XIA Hong 《科学通报(英文版)》2005,50(21):2487-2492
Based on the tree ring width index of Pinus tabulaeformis, precipitation in the last 140 years was reconstructed at south margin of the Tengger Desert. The results indicated that there were obvious fluctuations of dry-wet changes in precipitation: two wet periods occurred during 1868-1876 and 1932-1939, and two dry periods during 1877-1894 and 1924-1932, however, the years 1887 and 1888 were a little wet. There were small changes in precipitation during 1895-1923 and 1940-2000. As compared to the average, the maximum increasing range of precipitation amounted to 56% during the wet periods, and 42% during the dry periods. And the range of variability of precipitation exceeded 30% in 19 years. There was no obvious consistent drying or wetting trend in the last 140 years. But since 1940 fluctuating scope of precipitation tended to be smaller, while the frequency of the fluctuation tended to be larger. Power spectrum analyses suggested that precipitation of south margin of the Tengger Desert had significant periodicities of 2.46-2.64 a and quasi periodicity of 11.67 a. 相似文献
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67.
Wenshou Wei 《科学通报(英文版)》2000,45(12):1137-1142
The research on the respondence and feedback of modern sand deserts to the climate change is an important component part in
the studies on the global climate change. Deserts respond to the climate change, meanwhile, they affect the climate with their
feedback of peculiar environment during the respondence. Many researches on desert climate have been carried out at home and
abroad. However, there is little research on the respondence and feedback of modern fixed, semi-fixed and mobile deserts in
arid areas to the climate change, in which the factor analysis as well as the parameter changing effects is especially the
difficult problem all along. In this note, the parameters of the respondence and feedback of Gurbantunggut Desert to the climate
change are measured and analyzed, some variable parameters of water-heat exchange are obtained, and a numerical model of desertification
is developed according to a series of climate change of about 40 years and the variable relations of meteorological and physical
features of the sand surface in Gurbantunggut Desert. 相似文献
68.
《科学通报(英文版)》1991,36(14):1194-1194
69.
选取毛乌素沙漠东南部边缘萨拉乌苏河流域具有代表性的滴哨沟湾剖面全新统DGS1层段,通过测定样品的主量元素——Si O2、Al2O3、TOFE(全铁)、Ca O、Mg O、K2O、Na2O、Ti O2的含量并分析其特征,结合年代测定结果,探讨该地全新世气候演变.结果表明,主量元素表现出2个不同时期的不同波动方式:1CS~9P期间(0~3 760 a BP),Al2O3、TOFE、Ca O、Mg O、K2O、Na2O、Ti O2基本表现为在湖沼相中含量大于次生黄土,次生黄土中含量大于沙丘砂;10LS~21LS期间(3 760~11 000 a BP),Ca O、Mg O在湖沼相中出现峰值,尤其是在15LS(7 340~8 170 a BP)及其上下达到顶峰,其他主量元素表现为低值.通过分析发现,DGS1层段实际上是全新世以来多次东亚冬夏季风的交互演替过程下的堆积-风化产物,是气候地层的真实记录.依据CIA值与Si O2/(Al2O3+TOFE)比值,将DGS1层段主量元素信号记录的全新世气候可分为4个阶段:全新世早期气候好转、全新世鼎盛期、大暖期向寒冷期转变的波动期、降温不稳定和沙漠化频繁变化时期. 相似文献
70.
【目的】揭示乌兰布和沙漠1979年人工种植梭梭水分利用过程,以期为当地梭梭林的经营管理提供理论参考。【方法】利用PS-TDP8树木茎流监测系统和自动气象站对乌兰布和沙漠梭梭的液流变化及其周围的气象因子进行观测。【结果】梭梭晴天茎干液流日变化呈“单峰型”。春、夏、秋季梭梭茎干液流连日变化趋势一致,白天液流速率高于夜间,且夜间液流速率变化幅度小。5、7、9月时茎干直径12.5 cm的梭梭液流启动时间均早于直径8.95 cm的梭梭,平均液流速率也较高。茎干直径12.5 cm的梭梭在5、7、9月的液流峰值分别为2.90、4.18、3.15 cm/h,液流日累积量分别为12.29、14.23、9.44 L;茎干直径8.95 cm的梭梭同时期液流峰值分别为1.06、1.20、1.07 cm/h,液流日累积量分别为2.84、3.68、3.10 L;同一茎干直径梭梭在7月的液流日累积量最大。梭梭液流日变化中,晴天为“单峰型”,雨天呈“双峰型”;雨天液流峰值及夜间液流均低于晴天。夏季茎干液流启动时间最早,峰值出现时间最早,峰值最大;春季液流启动时间最晚,峰值出现时间最晚,峰值最小。春、夏、秋季梭梭夜间均存在微弱液流。【结论】影响梭梭液流速率的气象因子中,春季主要为太阳总辐射、空气温度、风速,夏季主要为太阳总辐射、空气相对湿度、风速,秋季主要为太阳总辐射、空气温度。 相似文献