New Thoughts of Comprehensive Development and Utilization of Salt Lake Resources in Qinghai Province     

DU Guangwei 《《地质学报》英文版》2014,88(Z1):417-417

正Qinghai Province has unique salt lake resources in China characterized by multicomponent,big storage,multi types and easy exploitation.These salt lake resources are concentrated in Qaidam Basin.  相似文献   

Long-term Changes in the Saline Lake Qarun(Egypt)     

Gamal EL-SHABRAWY  Mohamed GOHAR  Mousa GERMOUSH  Elena ANUFRIIEVA  Nickolai SHADRIN 《《地质学报》英文版》2014,88(Z1):180-182

正1 Introduction There is now ample evidence of the impacts of the recent climate change and anthropogenic activities on different saline lake ecosystems.All over the world salt lakes are threatened by climate change,water diversions upstream for agricultural purposes,watershed changes,introduction of aliens,etc.that result in catastrophic  相似文献   

Stable Isotope and Element Geochemistry of Saline Springs in Evaporite-bearing Mengla Basin,South Yunnan,China     

ZHANG Xiying  MA Haizhou  GAO donglin  MIAO Weiliang  LI Yongshou 《《地质学报》英文版》2014,88(Z1):176-177

正1 Introduction Mengla Basin is a sub-basin in southern evaporitebearing Lanping-Simao Basin.There are many salt springs in the basin.In 2012,11 spring samples were collected for analyses of chemistry and boron,hydrogen and oxygen  相似文献   

Ice‐cover variability on shallow lakes at high latitudes: model simulations and observations     

Claude R. Duguay  Greg M. Flato  Martin O. Jeffries  Patrick Mnard  Kim Morris  Wayne R. Rouse 《水文研究》2003,17(17):3465-3483

A one‐dimensional thermodynamic model for simulating lake‐ice phenology is presented and evaluated. The model can be driven with observed daily or hourly atmospheric forcing of air temperature, relative humidity, wind speed, cloud amount and snowfall. In addition to computing the energy balance components, key model output includes the temperature profile at an arbitrary number of levels within the ice/snow (or the water temperature if there is no ice) and ice thickness (clear ice and snow‐ice) on a daily basis, as well as freeze‐up and break‐up dates. The lake‐ice model is used to simulate ice‐growth processes on shallow lakes in arctic, sub‐arctic, and high‐boreal forest environments. Model output is compared with field and remote sensing observations gathered over several ice seasons. Simulated ice thickness, including snow‐ice formation, compares favourably with field measurements. Ice‐on and ice‐off dates are also well simulated when compared with field and satellite observations, with a mean absolute difference of 2 days. Model simulations and observations illustrate the key role that snow cover plays on the seasonal evolution of ice thickness and the timing of spring break‐up. It is also shown that lake morphometry, depth in particular, is a determinant of ice‐off dates for shallow lakes at high latitudes. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

Development of a diatom-based specific conductivity model for the glacio-isostatic lakes of Truelove Lowland: implications for paleoconductivity and paleoenvironmental reconstructions in Devon Island lakes, N.W.T., Canada     

Sai L. Ng  Roger H. King 《Journal of Paleolimnology》1999,22(4):367-382

Diatoms are identified and enumerated from the surface sediments of 100 lakes of Truelove Lowland, Devon Island, N.W.T., Canada. These lakes range from large oligotrophic lakes, to small tundra ponds, to coastal marine lagoons which are diverse in terms of ionic concentration and composition. The relationship between diatoms and 15 limnological variables is examined using Canonical Correspondence Analysis (CCA). Specific conductivity is identified as the most important variable influencing the distribution of diatoms in the Truelove lakes. A Weighted Averaging (WA) calibration model is developed to predict diatom-inferred specific conductivity. The reliability of the model is tested by evaluating the correlation between observed and diatom-inferred values and determining the error of prediction by bootstrapping. The applicability of the predictive conductivity equation is demonstrated by reconstructing the paleoconductivity history of Fish Lake.  相似文献   

Hydrogeological investigation of Chappice Lake, southeastern Alberta: Groundwater inputs to a saline basin     

S.J. Birks  V. N. Remeda 《Journal of Paleolimnology》1999,21(2):235-255

Sediment cores from Chappice Lake, a hypersaline, groundwater-fed lake in southeastern Alberta, have been used in previous studies to reconstruct Holocene climate using lake levels as a source for proxy climate data. This assumes that the lake is fed by a shallow groundwater system sensitive to changes in climate. In this study we use the dynamics and chemistry of groundwater entering the lake to test this hypothesis.Groundwater inputs calculated from historical records using a simple water budget were highest during periods when the precipitation deficit was high. Over specific time intervals, the expected relationship between lake volumes and climate were not always found. Feedback loops between lake levels and groundwater input, and time lags within the system are the mechanisms proposed to explain these discrepancies.Field measurements suggest discharge of a local surficial groundwater system. Slug tests reveal a high conductivity system (K = 10-5 m/s) surrounding the lake. Hydraulic heads measured in standpipe, multilevel and minipiezometers installed around Chappice Lake show that the lake is situated in a closed hydraulic head contour. Hydraulic heads and water table elevations show strong annual fluctuations corresponding to seasonal changes in recharge. Horizontal hydraulic gradients measured in areas of groundwater springs indicate a strong horizontal component of flow towards the lake. Vertical hydraulic gradients are low and indicate the upward flow of water consistent with the discharge of a shallow, surfical groundwater system.Groundwater sampled from deposits surrounding Chappice Lake and springs feeding the lake have compositions similar to both shallow surficial aquifers and bedrock aquifers suggesting that the lake may be receiving inputs from both sources. However, evaporation simulations using PHRQPITZ, show that the evaporation of water typical of bedrock aquifers result in a mineral assemblage and brine composition different from that found at Chappice Lake. This suggests that discharge of a regional groundwater system can be eliminated as a dominant source over the lake's history. Evaporation simulations suggest that evaporation of groundwater from shallow surficial deposits can best explain the present mineral assemblage and brine chemistry and were likely the dominant source of water to the lake.Bedrock and shallow surficial groundwater sources have different chemistries and isotopic compositions. In hydrogeological settings such as Chappice Lake where more than one source may contribute to the lake, the relative importance of the different sources may change with changes in climate. If the source water composition to the lake changes, identifying changes in climate or hydrology based on changes in the composition of the lake preserved in sediment core will be made more difficult. This may complicate paleoclimate and paleohydrological reconstructions that rely on mineralogical and isotopic data.  相似文献   

物理探查方法在土壤改良中的应用研究   总被引：4，自引：0，他引：4  

郭秀军  章光新  谭笑平 《地理科学》1999,19(5):470-474

如何快速全面的了解整个改良区的土层分布情况及盐碱化程度,如何对改良的效果进行了有效的检测,是盐碱地改良工作中的所要解决的问题,应用物理探查的方法解决这些问题,证实其在盐碱地的改良工程中是一种可行,有效的方法,并拟在国家“九五”重点科技攻关项目专题－松嫩平原盐碱地综合治理与农业持续发展研究中采用此项技术方法,进行跨学科的技术应用研究。  相似文献   

Quaternary charophytes from Salina del Bebedero, Argentina: their relation with extant taxa and palaeolimnological significance     

Adriana García 《Journal of Paleolimnology》1999,21(3):307-323

Charophyte (Charales, green macroscopic algae) assemblages found in Quaternary shoreline sediments from Salina del Bebedero, Argentina, are described in detail, illustrated, and statistically analysed. Fossil gyrogonites, Late Pleistocene and Holocene in age, of Chara cf. hispida var. major (Hartman) Wood, Chara halina García, Chara hornemannii Wallmann, Chara bulbillifera (Donterberg) García, Lamprothamnium haesseliae Donterberg and Lamprothamnium succinctum (Braun ex Ascherson) Wood were identified. A comparison with extant charophyte species of similar ecological requirements allowed for an accurate systematical determination and provided useful data for complementary palaeoecological and palaeobiogeographical approaches. On this basis, a reconstruction of palaeo-salinities for the Salina del Bebedero lake, represented by eleven palaeo-beaches, is proposed. Also the associations of charophytes with the ostracods Cyprideis sp., Limnocythere sp., Pampacythere sp., Cypridopsis sp., Darwinula sp., Ilyocypris gibba (Randohr) Brady and Norman, and the foraminifers Ammonia sp., Elphidium gunteri Cole, Quinqueloculina sp., and one species of Discorbacea are analysed, since they are present in both the fossil and modern environments.  相似文献   

南极大陆沿海湖泊生态结构研究   总被引：2，自引：1，他引：1       下载免费PDF全文

王自磐  atrick Deprez 《极地研究》1999,11(2):11-22

南极大陆沿海地带是南极海、陆、冰的交集带,它同时受到来自海洋、大陆冰以及人类活动的影响,因而成为南极生态环境最脆弱的环节。存在于该地带的许多湖泊,因其各自的地理环境和发育过程,以及所受诸多外部因子如气候、降水等的不同影响,不同湖泊中水体的理化因子差异很大,由此造成湖泊中生物种类分布和生态结构的显著不同。本文报道了对南极大陆沿海维斯特福尔德丘陵和拉斯曼丘陵等地湖泊中以浮游生物为主体,各类生物的组成分布和群落结构进行考察研究的结果,并分析讨论了不同类型湖泊的生物多样性、生物营养结构及其与环境的关系,为深入研究全球气候变化对南极区域环境的影响,和制订南极生态环境保护决策提供科学依据。  相似文献   

Inland saline lakes of Wadi El Natrun depression, Egypt     

Amany G. Taher 《International Journal of Salt Lake Research》1999,8(2):149-169

The morphology and geochemistry of saline lakes in the Wadi El Natrun depression were studied. All lakes had pH values of 8.5--9.5 and a salinity from 283 to 540 g/L. The main ionic components were sulphate, chloride, carbonate and sodium. Traces of magnesium were also present. The water of the lakes is of the Cl^– to SO ₄ ^2– -Cl^– type. Increased Cl^– in Wadi El Natrun brines can increase metal solubility due to the formation of soluble chloro-complexes of trace elements. The metal concentrations decrease in the order: Pb > Cu > Cd > Ni > Zn > Fe > Mn. The characteristics of Wadi El Natrun saline lakes are compared with those from other saline lakes.  相似文献