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Anomalous propagation conditions of electromagnetic wave observed over bosten lake, China in July and August, 2014

Chinese Physics B 2016年第2期25卷 148-158页

作者：孙正宁辉唐敬谢永杰石鹏飞王建华王柯 Northwest Institute of Nuclear Technology Xi'an 710024 China

Atmospheric duct is a common phenomenon over large bodies of water, and it can significantly affect the performance of many radio systems. In this paper, a two-month（in July and August, 2014） sounding experiment in ducting conditions over bosten lake was carried out at a littoral station（41.89°N, 87.22°E） with high resolution GPS radiosondes, and atmospheric ducts were observed for the first time in this area. During the two months, surface and surface-based ducts occurred frequently over the lake. Strong diurnal variations in ducting characteristics were noticed in clear days. Ducting occurrence was found at its lowest in the early morning and at its highest（nearly 100%） in the afternoon. Duct strength was found increasing from early morning to forenoon, and reaching its maximum in the afternoon. But contrarily, duct altitude experienced a decrease in a clear day. Then the meteorological reasons for the variations were discussed in detail, turbulent bursting was a possible reason for the duct formation in the early morning and the prevailing lake-breeze front was the main reason in the afternoon. The propagation of electromagnetic wave in a ducting environment was also investigated. A raytracing framework based on Runge–Kutta method was proposed to assess the performance of radio systems, and the precise critical angle and grazing angle derived from the ray-tracing equations were provided. Finally, numerical investigations on the radar performance in the observed ducting environments have been carried out with high accuracy, which demonstrated that atmospheric ducts had made great impacts on the performance of radio systems. The range/height errors for radar measurement induced by refraction have also been presented, too, which shows that the height errors were very large for trapped rays when the total range was long enough.

关键词： bosten lake atmospheric duct diurnal ducting variation ray-tracing equations

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Organochlorine pesticides and polycyclic aromatic hydrocarbons in water and sediment of the bosten lake,Northwest China

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Journal of Arid Land 2017年第2期9卷 287-298页

作者： SHEN Beibei WU Jinglu ZHAO Zhonghua State Key Laboratory of lake and Environmental Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

We evaluated organic pollution in bosten lake, Xinjiang, China, by measuring the concentrations and distributions of organochlorine pesticides （OCPs） and polycyclic aromatic hydrocarbons （PAHs）. Water and sediment samples were collected from 19 sites 031-1319） in the lake for analysis. Our analytical results show that the concentrations of total OCPs in water ranges from 30.3 to 91.6 ng/L and the concentrations of PAHs ranges from undetectable （ND） to 368.7 ng/L. The concentrations of total OCPs in surface （i.e., lake bottom） sediment ranges from 6.9 to 16.7 ng/g and the concentrations of PAHs ranges from 25.2 to 491.0 ng/g. Hexachlorocyclohexanes （HCHs） and dichlorodiphenyltrichloroethanes （DDTs） account for large proportions of the OCPs. Low α- to γ-HCH ratios in both water and sediment samples indicate possible contributions from both industrial products and lindane. DDTs in water are probably from historical input, whereas DDTs in sediments are from both historical and recent inputs. Moreover, DDT products in both water and sediments were from multiple sources in the northwestern part of the lake（B11, B12, B13, and B14）. Fugacity ratios for DDT isomers （p,p＇-DDE and p,p＇-DDT） at these sites were generally higher than equilibrium values. These results suggest that the input from the Kaidu River and diffusion of DDTs from the sediment to the water are responsible for DDT pollution in the water. Lower-molecular-weight PAHs, which originate primarily from wood and coal combustion and petroleum sources, represent the major fraction of the PAHs in both water and sediment samples. Our findings indicate that OCPs and PAHs in bosten lake can be attributed primarily to human activities. A risk assessment of OCPs and PAHs in water and sediment from bosten lake, however, suggests that concentrations are not yet high enough to cause adverse biological effects on the aquatic ecosystem.

关键词： organochlorine pesticides (OCPs) polycyclic aromatic hydrocarbons (PAHs) bosten lake surface water and sediment spatial distribution

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Carbon and Oxygen Isotopic Composition of Surface-Sediment Carbonate in bosten lake (Xinjiang,China) and its Controlling Factors

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 386-395页

作者： Steffen MISCHKE Alexander PROKOPENKO Freie University Berlin BerlinGermany Department of Geological Sciences University of South CarolinaColumbiaSouth CarolinaUSA

bosten lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inlet and the single outlet in the western part of the lake. The analytical results show that the carbon and oxygen isotopic composition of recent lake sediments is related to this specific lacustrine depositional environment and to the resulting carbonate mineralogy. In the southwestern lake region between the Kaidu River inlet and the Kongqi River outlet, carbon isotope composition （δ^13C） values of the carbonate sediment （-1‰ to -2‰） have no relation to the oxygen isotope composition of the carbonate （δ^18O） values （-7‰ to -8‰）, with both isotopes showing a low variability. The carbonate content is low （〈20%）. Carbonate minerals analyzed by X-ray diffraction are mainly composed of calcite, while aragonite was not recorded. The salinity of the lake water is low in the estuary region as a result of the Kaidu River inflow. In comparison, the carbon and oxygen isotope values are higher in the middle and eastern parts of the lake, with δ^13C values between approximately ＋0.5‰ and ＋3‰, and δ^18O values between -1‰ and -5‰. There is a moderate correlation between the stable oxygen and carbon isotopes, with a coefficient of correlation r of approximately 0.63. This implies that the lake water has a relatively short residence time. Carbonate minerals constitute calcite and aragonite in the middle and eastern region of the lake. Aragonite and Mg-calcite are formed at higher lake water salinity and temperatures, and larger evaporation effects. More saline lake water in the middle and eastern region of the lake and the enhanced isotopic equilibrium between water and atmospheric CO2 cause the correlating carbon and oxygen isotope values determined for aragonite and Mg-calcite. Evaporation and biological processes are the main reasons for the salinity and carbonate mi

关键词： carbonate aragonite calcite stable carbon and oxygen isotope composition bosten lake

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High-Resolution Records of the Holocene Paleoenvironmental Variation Reflected by Carbonate and Its Isotopic Compositions in bosten lake and Response to Glacial Activities

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1101-1115页

作者： ZHANG Chengjun ZHENG Mianping Alexander PROKOPENKO Steffen MISCHKE GOU Xiaohui YANG Qili ZHANG Wanyi FENG Zhaodong School of Resources and Environmental Sciences Lanzhou University Lanzhou 730000 Gansu China Center of Saline lake and Epithermal Deposit Chinese Academy of Geological Sciences Beijing 100037 China University of South Carolina Columbia SC 29205 USA Freie University Berlin Berlin 12249 Germany

The Early Holocene paleoclimate in bosten lake on the northern margin of the Tarim Basin, southern Xinjiang, is reconstructed through an analysis of a 953 cm long core （BSTC2000） taken from bosten lake. Multiple proxies of this core, including the mineral components of carbonate, carbonate content, stable isotopic compositions of carbonate, Ca/Sr, TOC and C/N and C/S of organic matter, are used to reconstruct the climatic change since 8500 a B.P. The chronology model is made by nine AMS 14C ages of leaves, seeds and organic matter contained in two parallel cores. The climate was cold and wet during 8500 to 8100 a B.P. Temperature increased from 8100 to 6400 a B.P., the climate was warm and humid, and the lake expanded. The lake level was highest during this stage. Then from 6400 to 5100 a B.P., the climate became cold and the lake level decreased slightly. During the late mid-Holocene, the climate was hot and dry from 5100 to 3100 a B.P., but there was a short cold period during 4400 to 3800 a B.P. At this temporal interval, a mass of ice and snow melting water supplied the lake at the early time and made the lake level rise. The second highest lake level stage occurred during 5200 to 3800 a B.P. The climate was cool and wet during 3100 to 2200 a B.P., when the lake expanded with decreasing evaporation. The lake had the last short-term high level during 3100 to 2800 a B.P. After this short high lake level period, the lake shrank because of the long-term lower temperature and reduced water supply. From 2200 to 1200 a B.P., the climate was hot and dry, and the lake shrank greatly. Although the temperature decreased somewhat from 1200 a B.P. to the present, the climate was warm and dry. The lake level began to rise a little again, but it did not reach the river bed altitude of the Konqi River, an outflow river of the bosten lake.

关键词： carbonate isotopic composition glacial activity paleoenvironmental variation bosten lake

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The Palaeoclimate record around 5000 a BP in the Westerlies bosten lake,Xinjiang,China

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地球环境学报 2011年第1期 330-330页

作者： ZHANG Wan-yi ZHANG Cheng-jun GAO Dou SUN Fei-fei College of Resources and Environmental Sciences Lanzhou University

bosten lake（86°40'87°26'E,41°56'42°14'N）,one of the largest freshwater lakes in the interior of China,is located in the southeastern corner of the Yanqi Basin at the southern piedmont of the Tianshan Mountains,northwestern *** lake,about 1000 km2in area,is the terminal lake of the Kaidu River,the only permanent inflowing river,and is the headwater（i.e.,the source） of the Kongqi *** present average lake level is about 1048 m a.s.L and the average depth is about 8 m with a maximum depth of 17 *** mean annual precipitation is only 68 mm with a mean annual evaporation of2000 mm within the low-elevation part of the drainage *** water balance of bosten lake is primarily controlled by the lake evaporation and inflowing runoff of the Kaidu River that is contributed by snow- and glacier-melt water in high elevations and the precipitation within the entire drainage basin.A 953 cm core BSTC2000 of bosten lake in the soudiern Xinjiang of northwestern China reconstructed the palaeocliamtic change in detail interval about 6400 cal a BP to 5000 cal a BP based on a chronology supported by9 AMS C dates publishes in The *** the Sr/Ca（as a salinity proxy）,8 O and 8 C of bulk sediment carbonate（as a temperature proxy）,it is shown that this period was cold but high effective humidity climate intercrossed five warm/low effective humidity *** periods of about 6400～5975 a BP,5725～5400 a BP,5325～5250 a BP,5200～5150 a BP,5080～5025 a BP and 5000～4950 a BP were the cold and high effective *** are fitted well with the moving of glaciers in Xinjiang and Tibet plateau,and have a well remote relationship with Neolithic Culture contabescence around 5000 a BP in the southern part of China ***'s more important to prove and inosculate the pattern of Holocene climatic variations summarized by Denton and Karlen（1973） as the moving of glaciers and pollen records in the south and north *** this bosten lake core BSTC2000,we can believe conv

关键词： bosten lake paleoclimate 5000 a BP westerlies Xinjiang

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Characteristics of Stable Isotopes in an Inland lake and Their Implications for Water Management in Northwestern China

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Journal of Water Resource and Protection 2016年第6期8卷 631-641页

作者： Honghua Zhou Weihong Li Yun Wang Zhaoxia Ye State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Xinjiang Normal University Urumqi China

bosten lake is the largest inland freshwater lake in China, functioning as a critical control and allocation facility for agricultural, industrial, ecological and social development in southern Xinjiang in northwestern China. The distribution of stable isotopes, spatial and temporal variations of δ18O, and hydrograph separation of bosten lake and its principal recharge rivers—the Kaidu River and the Huangshuigou River—were analyzed using isotope composition. Hydrograph separation indicated that bosten lake water comprised four components as follows: river runoff, groundwater, agricultural and industrial drainage, and local precipitation. Their contributions were 31%, 35%, 25%, and 9%, respectively. Irrigation drainage and industrial wastewater, enriched high TDS, were the main factors affecting the water quality of bosten lake. The δ18O of lake water, which was significantly reduced compared with river water, remained below the local meteoric water line (LMWL), indicating strong evaporation in the lake, especially during summer. The spatial and temporal distribution of δ18O exhibited slow water circulation in the lake. Both the Kaidu River and the Huangshuigou River depend on alpine precipitation and glacier snow, especially the Kaidu River, where ice-snow-melt water accounts for 43% of the river runoff. These rivers are sensitive to climate change. The bosten lake inflows would be reduced by the decrease in river runoff and groundwater under future climate change. To improve water quality and reduce evaporative loss, the amount of wastewater should be strictly restricted by local government, and water diversions from bosten lake should be concentrated between May and September.

关键词： Isotope Composition Spatial and Temporal Variation Hydrograph Separation bosten lake Arid Area

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