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1.
Yoshiko Kawabata Tsuneo Tsukatani Yukio Katayama 《International Journal of Salt Lake Research》1999,8(2):99-112
Lake Balkhash is one of the many closed lakes in Central Asia. Mechanisms of demineralization in Lake Balkhash were considered from results of surveys undertaken on the lake and along the Ili River. Electrical conductivity (EC) values at the eastern coast in south-western Lake Balkhash were higher than those of the western coast. The Ili River enters at the south-western corner of the lake, so that EC values of this area are low. This water flows westwards. The distribution of Ca2+ concentrations showed that these were lower value in Lake Balkhash than along the Ili River, implying Ca2+ removal by the lake. Amongst suspended mineral matter in the lake occur calcite and dolomite. Thus, a possible mechanism of calcium removal is that it is removed as crystals of calcite or dolomite. SO
4
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concentration within the lake has increased for the past 37 years. This may be caused by the discharge into the lake from the city of Balkhash of waste water from a copper smelter. 相似文献
2.
Alexander A. Prokopenko Christopher St. G. C. Kendall 《Journal of Paleolimnology》2008,40(4):1185-1192
This paper seeks to arrive at a consistent interpretation of (1) the age model, (2) the grain size record, and (3) seismic reflection data from Lake Hovsgol (a.k.a Khubsugul or Hövsgöl), Mongolia, reported by Fedotov et al. (2007, earlier by Fedotov et al. 2002, 2004). In their most recent contribution, the grain size record of the KDP-01 drill core is interpreted as a climatic signal while little consideration is given to lake-level changes and hence to basin-wide changes in depositional setting evident from seismic profiles; also, a nearly linear age model is at odds with the seismic evidence for a major angular unconformity in the sediment strata. The lack of regional seismic stratigraphic analysis has thus led to an improbable interpretation of the Lake Hovsgol sediment grain size record and ultimately to an improbable scenario of Mongolian glaciation history. Using the available seismic profiles, here we show that the drill core penetrated several transgressive/regressive sedimentary sequences and a major angular unconformity. Therefore, the drilled sediment section cannot represent continuous sediment accumulation and the Brunhes age model across the unconformity cannot be nearly linear; the time interval representing a hiatus remains to be determined. The assumed nearly linear age/depth relationship in the upper 23 m above the angular unconformity is also an unlikely relationship, given the evidence of repeated changes in lake level, and hence in the depositional setting and sedimentation rates. We further propose a qualitative reference model for changes in the Lake Hovsgol depositional setting (presented as a step-by-step animation – see supplementary material) based on manually ‘backstripping and rebuilding’ the seismic pattern. We argue that this model provides a useful template of the likely sediment facies changes in the deep axial part of the Hovsgol basin: our crude model in fact captures the major depositional trends in the KDP-01 drill core section located some 10 km NW along the seismic line. We contend that changes in the depositional setting provide the first-order control on sediment grain size in the Hovsgol record. Our study provides important new constraints on the nature of sedimentary proxy records in Lake Hovsgol and on their interpretation as a record of Mongolian glaciation history. 相似文献
3.
M. Ghaheri M.H. Baghal-Vayjooee J. Naziri 《International Journal of Salt Lake Research》1999,8(1):19-22
The major hydrological, morphometric and chemical features of Lake Urmia, a large salt lake in Iran, are briefly reviewed.
Some comments are made on bacteriological quality of the lake sediments. 相似文献
4.
Relationships among conductivity, temperature, total dissolved solids (TDS), and density were determined for hypersaline brine (TDS, 83 g kg–) from Mono Lake. A theoretical estimate of density based on ionic composition and calculated partial molar volumes compared well with actual measurements (difference, 390 ppm). However, an empirically derived equation of state based on temperature and conductivity provides the most accurate density estimates (residual errors, 190 ppm) and can be used with data collected with CTD profilers. 相似文献
5.
Yoshiko Kawabata Hiroyuki Nakahara Yukio Katayama Norio Ishida 《International Journal of Salt Lake Research》1997,6(1):5-16
The Aral Sea, Lake Balkhash, and Lake Kamyslybas are closed lakes in Central Asia. They range from oligosaline to metasaline.
The salinity of the Aral Sea has increased by more than 30 g L−1 since widespread irrigation began in its catchment area. Few studies of the phytoplankton have been conducted on these lakes
since extensive irrigation started. The investigation reported here compares the flora of phytoplankton in these saline lakes.
In the Small Aral Sea, phytoplankton density gradually decreased with increasing electrical conductivity (EC) (∼ salinity),
but there was no such relation in Lake Balkhash and Lake Kamyslybas. In the Aral Sea, Dinophyceae and Bacillariophyceae were
frequently observed in most areas of high EC value, and Cyanophyceae were most conspicuous in the area of medium and lower
EC values. In Lake Balkhash, Cyanophyceae were most conspicuous, but Chlorophyceae were also noticeable. Most Cyanophyceae
in Aral Sea formed filaments with heterocysts. The distinct characteristic of the phytoplankton of the Lake Balkhash was that
all dominant species form colonies covered with a gelatinous film. Siliceousplankton diversity gradually decreased with increasing
EC values in the Aral Sea and Lake Balkhash. 相似文献
6.
Integration of reflection seismic and sediment grain-size data from Lake Khubsugul (Northern Mongolia): a reply to Prokopenko and Kendall 总被引:1,自引:0,他引:1
Prokopenko and Kendall (J Paleolimnol doi:, 2008) criticise the work presented in Fedotov et al. (J Paleolimnol 39:335–348, 2008), and instead propose an alternative
interpretation for the grain-size evolution recorded in the KDP-01 core, retrieved from the central part of Lake Khubsugul.
Their interpretation is based (i) on a seismic-stratigraphic re-interpretation of sparker seismic profile khub012 (which they
copied from Fedotov et al. (EOS Trans 87:246–250, 2006)), (ii) on the presupposition that changes in lake level are the dominant
control on facies distribution in Lake Khubsugul, and (iii) on the invalidation of our age-depth model. In this reply to their
comment, we demonstrate that they interpreted seismic artefacts and geometries caused by changes in profile orientation as
true stratigraphic features and that the lake-level reconstruction they derive from this interpretation is therefore incorrect.
We also demonstrate that their grain-size predictions, which they consider to be predominantly driven by changes in lake level,
are inconsistent with the measured sulphate concentration, which is a demonstrated proxy of lake level in Lake Khubsugul,
and with the measured grain-size record. Finally, we point out that even if there would be a problem with the age-depth model,
this problem would not affect the part of the sedimentary sequence discussed in Fedotov et al. (J Paleolimnol 39:335–348,
2008). 相似文献
7.
A. Egorov 《International Journal of Salt Lake Research》1998,7(2):109-111
Temperatures recorded in August 1985 in the water column and sediments of Lake Sasykkul, a small mountainous saline lake in Tadzikstan, are noted. The lake was weakly heliothermal and the underlying permafrost was depressed. 相似文献
8.
Historical and recent changes in the nature of Lake Texcoco, a saline lake in Mexico, are described. These changes are particularly important since they significantly affect water supply, drainage and other urban issues in Mexico City, Mexico's largest city and capital located within the general boundaries of the lake basin and gradually sinking (mean annual sinking rate is 30 cm). After brief reviews of the present status of the lake and background geological, palaeolimnological and climatic features, human activities during historical and recent times are considered. Of particular note have been drainage basin activities, diversion of inflows, pollution and over-exploitation of groundwater and biological resources (especially fish and waterfowl). The major effects of these activities are water shortages, soil erosion, salinization, dust storms, sinking ground, poor water quality and decreased biological resources. Conservation measures are discussed. 相似文献
9.
J.K. Kairu 《International Journal of Salt Lake Research》1999,8(3):253-266
29 specimens of a cichlid fishSarotherodon (=Tilapia) alcalicus grahami were collected from Lake Nakuru between September and October 1990 and samples of liver, kidney, muscle, brain and fat were
removed for analysis of organochlorine pesticide and metal residues. Fat was extracted and the concentration of three lindane
(BHC/HCH) isomers (alpha, beta andgamma), aldrin, heptachlor, heptachlor-epoxide, endrin, dieldrin, DDD, DDE and DDT was determined. Fish muscle samples were digested
and the concentration of mercury, arsenic and cadmium was also determined.
No residues of o,p1-DDD, p,p1-DDD, aldrin, endrin and dieldrin were detected. The highest residue concentration detected was 0.062 mg kg−1 of p,p1-DDT. The mean pesticide residue concentration levels were generally low. The [p,p1-DDT]/[p,p1-DDE] ratio of 1.22 indicated that the residues of the parent DDT compound exist in the Lake Nakuru ecosystem. There was a
negative fish length: DDE concentration relationship. Similarly, there was a very weak negative relationship between arsenic
concentration and length of fish. The concentrations of metal residues were considerably low. The median arsenic and cadmium
concentrations were 0.03 mg kg−1 and <0.1 mg kg−1, respectively. The concentrations of mercury, with a median level of <0.01 mg kg−1, were particulary low and did not approach a level that would give rise to public health concern. Metal and pesticide residue
concentration in fish in 1970 and 1990 does not show a significant increase. From these results, Lake Nakuru is presently
not exposed to heavy pesticide and metal contamination, but there is a gradual build-up of these residues in the biota. 相似文献
10.
Potential salinity limitations on nitrogen fixation in sediments from Mono Lake, California 总被引:2,自引:0,他引:2
David B. Herbst 《International Journal of Salt Lake Research》1998,7(3):261-274
Mono Lake is a hypersaline alkaline lake in the high altitude Great Basin desert of eastern California. Algal productivity
of the lake is nitrogen-limited, and a contributing source is derived from benthic nitrogen fixation. Lake level and salinity
have fluctuated with natural climatic variations but have also been affected by the diversion of tributary streams. This research
examines the influence of varied salinity and lake level on the potential for benthic nitrogen fixation in Mono Lake. A sediment-surface
microbial mat community was exposed directly, and in acclimated cultures, to a range of Mono Lake salinities under anaerobic
incubations and the activity of nitrogenase assayed by acetylene reduction. Activity was stimulated in light, but also occurred
in darkness. Over an experimental salinity range from 50 to 150 g L−1 TDS, nitrogenase activity was reduced by 90 per cent, with the activity persisting at the highest salinity being attributable
to dark fixation alone. Between a salinity of 50 g L−1, occurring in Mono Lake over 50 years ago, and 100 g L−1, nitrogenase activity was reduced by nearly half. Changes in the area of the littoral zone at varied lake levels also affect
the total amount of potential benthic nitrogen fixation in the lake. An accounting of yearly inputs of nitrogen to Mono Lake
suggests N2-fixation could contribute as much as 76–81 percent of the total. Inhibition of nitrogen fixation rates by increased salinity
could limit the long-term nutrient supply and benthic primary productivity of this ecosystem. 相似文献
11.
Andrey Petrovich Fedotov Michael A. Phedorin Mark De Batist Galina A. Ziborova Alexsey Yu Kazansky Michael Yu Semenov Galina G. Matasova Andrey V. Khabuev Sergey A. Kugakolov Sergey V. Rodyakin Svetlana M. Krapivina Tom Pouls 《Journal of Paleolimnology》2008,39(3):335-348
We use high-resolution reflection seismic data and detailed grain-size analysis of a drill core (KDP-01) from Lake Khubsugul
(northern Mongolia) to provide an improved reconstruction of the glacial history of the area for the last 450 ka. Grain-size
analysis of suspended sediment load in modern rivers draining into the lake and of moraine material from the northern part
of the catchment shows that the silt fraction is transported to the central part of the lake mainly by river suspension, whereas
the clay fraction is mainly transported by glacial meltwater during deglaciation. The changes in of the clay/silt ratio in
Lake Khubsugul sediments correlates well with the standard global paleoclimate records: low clay/silt ratios indicate warm
climates, while a high clay/silt ratio reflects glacial erosion and cold climates. Pulses of clay input into the lake occur
at the final stages of glacial periods (i.e., glacial maxima and subsequent onsets of deglaciation). The periodicity in glacial
clay input in Lake Khubsugul is in tune with global periods of deglaciation, but there are differences in the intensity of
the deglacial events for MIS-12 and MIS-2. These differences are attributed to specific conditions in regional distribution
of moisture during glaciation, glacial ice volumes, and solar insolation intensity at the onset of deglaciation. Deglaciation
of the Khubsugul glaciers occurred in response to an increase in summer solar insolation above a threshold value of 490 W/m2. Two types of deglaciation can be distinguished: (1) slow melting during several tens of 1,000 years during weak increases
in summer insolation, and (2) short and fast melting during several thousands of years in response to strong increases in
summer insolation. The maximum ice volume in the area of Lake Khubsugul during the past 450 ka occurred during the period
of 373–350 ka BP (MIS 11a-10) and was caused by high levels of moisture in the region, whereas the MIS-2 and MIS-12 glacial
periods were characterized by minima in ice volume, due to the strong aridity in the region. 相似文献
12.
A. E. Poberezhnaya A. P. Fedotov T. Ya. Sitnikova M. Yu. Semenov G. A. Ziborova E. L. Otinova A. V. Khabuev 《Journal of Paleolimnology》2006,36(2):133-149
This paper deals with the investigation of the upper 11.6 m portion of a long drill core (KDP-01) taken from the bottom sediments of Lake Khubsugul. Ostracod species and their assemblages recovered from the core were analyzed. The data are compared with the carbonate and sulfate values obtained from bulk sediment, as well as with the flux of the coarse terrigenous fraction (>200 m) from the same core. Based on the previously calculated depth-age sedimentary model, the oldest age of the core studied here is about 230 ka. The four ostracod species recovered in the core are Cytherissa lacustris, Candona lepnevae, Limnocythere inopinata and Leucocythere sp. According to the distribution of those ostracods, we distinguish four main periods, each of about 50 ka long. Based on the ecological requirements of extant ostracods, two assemblages typifying a low water level and high salinity, on the first hand, and another representing freshwater and high lake level are recognized. The first “high salinity” ostracods correspond to “cold” periods as seen globally, while “freshwater” ostracods are associated with interglacials. Ostracod valves are absent during interglacial optima. This may be due to chemical dissolution of calcium carbonate related to organic matter decay at the initial stages of diagenesis, probably because during interglacials, in contrast to glacials, organic matter flux reaching the lake bottom were significantly higher. The periodicity in the development of ostracod species assemblages follows 17, 24 and 47 ka cycles related to orbital forcing. Its diversity is correlated with summer temperature fluctuations in northern altitudes for the past 230 ka. The maximum in species diversity follows the temperature maxima, by about 1.5 and 2 ka. Overall, the data obtained demonstrate a correlation between climatic changes and variations in specific and quantitative ratios of ostracod species during the last 230 ka. 相似文献
13.
14.
Magdy T. Khalil 《International Journal of Salt Lake Research》1997,6(4):323-330
Four limnological models (lake shoreline development (DL), Morphoedaphic Index (MEI), primary production and total nutrient input) have been applied to Lake Borollus to estimate
existing fish yield and future potential productivity. The estimated existing fish yield from the lake is about 1260 kg/ha
(i.e. 53,000 tons/annum), which is at or near its existing potential and is considered in the ultra enriched category. From
1931 to 1935, the estimated fish production of Lake Borollus was about 68 kg/ha, which is considered low enriched category,
while from1960 to 1970, the lake belonged to the moderately enriched category, where the estimated fish production was about
155 kg/ha, and then tremendously increased to about 580 kg/ha during the 1980's.Thisincrease in fish yield is mainly attributed
to the nutrient loading of the southern and eastern drains to the lake. In the long term, and based on existing nutrient input
to fish yield relationships, it is estimated that increased nutrient loading from drainage water may elevate its yield by
24, 580 tons by the year 2005 (i.e. total fish yield could be increased to 77,500 tons/annum).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
S. K. Murimi 《International Journal of Salt Lake Research》1994,3(1):65-74
Reasons why Lake Elmenteita and rivers flowing into it decreased in volume during 1958–1987 were investigated. The effects of changing climate, landcover and landuse were considered. The study suggested that falling lake water-levels are not due to climate change alone: landuse changes and river abstraction and damming may also be important. Long-term trends in rainfall and evaporation reveal various patterns: monthly evaporation has slightly decreased recently but with no effect on lake levels; rainfall has remained more or less constant in total amount, but monthly falls show increased variability. Although flows in rivers and streams are primarily determined by rainfall, other factors operate near the lake so discharge into the lake cannot be predicted from rainfall. Increased settlement and farming on former forested areas within the catchment and irrigation along rivers also indirectly affect discharge values. Additionally, accelerated soil erosion from farmed lands has led to a reduced lake volume following soil deposition in the lake. It is noted that landuse changes need to be carefully monitored because of their effect on lake levels. 相似文献
16.
Saline lakes in the lower Grand Coulee,Washington, USA 总被引:1,自引:0,他引:1
W. T. Edmondson 《International Journal of Salt Lake Research》1992,1(2):9-20
Changes in the limnology of two saline lakes, Lake Lenore and Soap Lake, in the lower Grand Coulee, Washington, between 1949
and the present are described.
This paper is an abbreviated version of Chapter 11 in: W.T. Edmondson,The Uses of Ecology: Lake Washington and Beyond, pp. 209–226. University of Washington Press, Seattle. The book is based upon lectures given by the author inthe Jessie and John Danz Lectures. The considerable interest of studies on Lake Lenore and Soap Lake in the lower Grand Coulee, the authoritative account of
these studies in the book, and the possibility that this account would not easily attract the attention of limnologists who
study salt lakes were behind the decision to reproduce the chapter. Its reproduction has been graciously permitted by the
author and the University of Washington Press. This permission is gratefully acknowledged. Whilst only Chapters 11 and 5 (Mono
Lake) directly concern salt lakes, the book as a whole is an outstanding account of how limnological studies (with focus on
those of Lake Washington) can serve humanity Ed. 相似文献
17.
18.
The fauna and flora of Lake Abalakh, a saline lake in Yakutia, eastern Siberia, Russian Federation, is described from a collection made in July, 1990. The fauna comprisedMoina mongolica, Metadiaptomus asiaticus, Brachionus plicatilis and larval ceratopogonids. The flora was much more diverse. It contained 82 taxa most of which were cyanophytes, bacillariophytes, and chlorophytes. Also present were cryptophytes (1 taxon), xanthophytes (5) and euglenoids (1). 相似文献
19.
Lake Balkhash,Kazakhstan 总被引:2,自引:0,他引:2
T. Petr 《International Journal of Salt Lake Research》1992,1(1):21-46
Lake Balkhash is a large (18,000 km3), closed, and slightly saline lake in the south-west of Kazakhstan. It is divided into two basins, a south-western and an
eastern basin. These have somewhat different limnological conditions, but the most obvious one is that the south-western basin
has a salinity of <2 g L−1 whereas the salinity of the eastern basin is ∼4 g L−1. Numerous fish and invertebrate introductions, many successful, have been made. In 1969, a dam impounding the Kapchagay reservoir
was constructed on the River Ili, the major river flowing into the lake. The impoundment of water in this reservoir caused
a fall of some 1.5 m in the water-level of the lake. This fall, together with other events on the catchment, caused considerable
damage to reedswamps in the lake, to the fishery and to conservation values. A number of suggestions has been made on how
to prevent further damage. Some, particularly those involving a moratorium on further filling of Kapchagay reservoir and irrigation,
have been implemented, at least in part. This has caused some remission in environmental damage and provides for cautious
optimism with regard to the lake’s future. Even so, the environmental status of the lake remains vulnerable and many dangers
persist. 相似文献
20.
2016年3月系统采集了青海可可西里东北部多秀湖和盐湖的湖水及其入湖冰川融水。研究发现,两个湖泊湖水中离子含量均较高,主要阳离子含量顺序均为Na~+Mg~(2+)K~+Ca~(2+),主要阴离子含量顺序均为Cl~-SO_4~(2-)HCO_3~-CO_3~(2-);而入湖冰川融水的离子含量非常低。根据库尔纳可夫—瓦良什科水化学分类标准,多秀湖湖水属于硫酸盐型—硫酸镁亚型,盐湖湖水属于硫酸盐型—硫酸钠亚型。多秀湖和盐湖湖水Li—Mg—B的相关性均为正相关,说明两个湖泊中这3种元素的物质来源、搬运条件及富集环境具有很强的相似性。由于气候变暖导致大量矿化度低的冰川融水注入盐湖,矿化度较低的卓乃湖和库赛湖决堤湖水泄入盐湖,使得盐湖的面积较1997年扩大了5倍,湖水的矿化度降低了约10倍,而多秀湖近些年湖水矿化度变化较小。多秀湖湖水矿化度以及Li~+、Mg~(2+)和B_2O_3含量均较高,具有较好的资源潜在利用价值。 相似文献