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The Effect of Urmia-Lake Water on Mechanical Strength Concrete with Various Admixtures  [cached]
Hadi Barghlame,M.A. Lotfollahi-Yaghin,Mehdi Mohammadrezaei,Babak Bahaminfar
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: This study has been investigated the effect of admixtures on the strength of concrete under water with high aggressive ions, for example under Urmia-lake water in West Azerbaijan, Iran. We made different types of concretes with the ratio of w/c and replaced different percentages of micro-silica, air-entraining, super plasticizer, corrosion-inhibiting and caulk with two types of cement I and II as well as investigating in both ordinary water and Urmia-lake water. The strength of pressure, tension, abrasion and freezing and melting was investigated on these samples. The results indicate that admixtures improved strength of concrete under water with high aggressive ions. Finally, the most proper mixture was presented using both types of cement (I and II) and optimal value for micro-silica, caulk and super plasticizer.
Investigation of Recent Changes in Urmia Salt Lake
Rezvantalab S.,Amrollahi M. H.
International Journal of Chemical and Environmental Engineering , 2011,
Abstract: Lake Urmia is a salt lake in northwestern Iran near Turkey. In recent years, the water level has been decreased. To predict the mineralprecipitation in water, Single ion activity coefficients of major ions in Urmia Salt Lake have calculated using Pitzer approach. Usingthe results, saturation index for mineral calculated. Urmia Salt Lake brines have shown increase in saturation indices during the last 20 years.
Urmia Lake (Northwest Iran): a brief review
Amin Eimanifar, Feridon Mohebbi
Aquatic Biosystems , 2007, DOI: 10.1186/1746-1448-3-5
Abstract: Lake Urmia (or Orumiyeh), is one of the largest permanent hypersaline lakes in the world and resembles the Great Salt Lake in the western USA in many respects of morphology, chemistry and sediments [1]. Despite this, and its several values, including conservation, little literature has been published on the lake and its biota[2-7]. The aim of the present paper is to provide a brief review based on previous and recent literature on various aspects of Urmia Lake with particular emphasis on conservation and management. Although we cannot provide an all inclusive coverage here, we hope that it will be sufficient to introduce this remarkable lake to the general reader.Urmia lake can be characterized as oligotrophic in terms of phytoplankton production in the range of 0.5–0.8 μg/l [6], with lower values compared to Great Salt Lake (0.5–3.5 μg/l) [8]. The predominance of the Na+ and Cl- ions illustrates the thalassohaline character of Urmia lake [9]. Therefore, Urmia Lake is an oligotrophic lake of thalassohaline origin [10] located in northwestern Iran at an altitude of 1250 m above sea level [6]. The total surface area ranges between 4750 km2 and 6100 km2 [11] depending on evaporation and water influx. The catchment area of the lake contains 21 permanent and ephemeral streams together with 39 episodic rivers, flowing through agricultural, urban and/or industrial areas that drain into this terminal lake, mostly without waste water treatment [12]. The maximum length and width of the lake are 128–140 km and 50 km, respectively [11,13]. The average and maximum depths are 6 m and 16 m, respectively [14]. The lake is divided into north and south parts separated by a causeway [15], which has a gap that allows for a limited exchange of water between the two arms [14].Considering the role of Artemia in Urmia Lake, the Iranian Fisheries Research Organization (IFRO) established the Artemia Research Center in Urmia in 2000. On the basis of the vital role of Artemia as a live food in
Thermodynamic quantities and Urmia Sea water evaporation
Nosrat Heidari, Mina Roudgar, Neda Ebrahimpour
Aquatic Biosystems , 2010, DOI: 10.1186/1746-1448-6-3
Abstract: Lake Urmia (or Orumiyeh), is one of the largest permanent hypersaline lakes in the world and resembles the Great Salt Lake in the western USA in many respects of morphology, chemistry and sediments [1]. Despite this, and its several values, including conservation, little literature has been published on the lake and its biota [2-7]. The predominance of the Na+ and Cl- ions illustrates the thalassohaline character of Urmia lake [8]. Therefore, Urmia Lake is an oligotrophic lake of thalassohaline origin [9] with an ionic strength between 5.5-7.5, located in northwestern Iran at an altitude of 1275 m above sea level. The total surface area ranges between 4750 km2 and 6100 km2 [10] depending on evaporation and water influx. The maximum length and width of the lake are 128-140 km and 50 km, respectively [10,11]. The average and maximum depths are 6 m and 16 m, respectively [12]. The Urmia lake is not a homogeneous body of water. There are horizontal variations in temperature and salinity but these are too small to make a difference on a climatic scale [13].The air temperature usually ranges between 0 and -20°C in winter, and up to 40°C in summer [14]. From this point of view, Urmia Lake is a critical asset for the region, because it acts to moderate these extremes [15].Hydrologic conditions are extremely important for the maintenance of a given water body's structure and function and affect many abiotic factors which, in turn, may impact the biota that develop in it [16].Because saline lakes occur primarily in endorheic basins, they may be particularly sensitive to environmental changes because their size, salinity and annual mixing regimes vary with alterations in their hydrologic budgets [17,18].The main cations in the lake water include Na+, K+, Ca+2, and Mg+2, while Cl-, SO4-2, HCO3- are the main anions [19]. Sodium ions are at slightly higher concentration in the south compared to the north of the lake, which could result from the shallower depth in the south, and a
Meteorological and water quality changes in Lake Trasimeno (Umbria, Italy) during the last fifty years  [cached]
Alessandro LUDOVISI,Elda GAINO
Journal of Limnology , 2010, DOI: 10.4081/jlimnol.2010.174
Abstract: This paper illustrates the results of an analysis performed on historical data of the main meteorological and water quality variables collected during the last fifty years in the basin of Lake Trasimeno, a shallow lake subjected to important water level fluctuations. The results reveal a significant increase of the annual mean of minimum and maximum air temperature, water temperature and solar radiation, and a significant reduction of precipitation and cloud cover, which have mostly occurred during the last twenty years. The decadal rate of warming observed in the last twenty years for air temperature (0.33 °C decade-1) is consistent with the estimate reported by the IPCC for the land-surface temperature in the Northern Hemisphere, whereas the surface water temperature in Lake Trasimeno shows a more marked increase (0.65 °C decade-1), comparable to that observed in other lakes of Mediterranean areas. On a monthly scale, the most significant variations are observed in late-spring and early summer months for temperature and solar irradiation, and in winter and spring months for rainfall, which result in an appreciable modification of the seasonal progression. The alterations of the thermal and hydrological balance of the lake have caused a progressive lowering of the water level and the emergence of evaporative conditions. As a consequence of the drought, a progressive accumulation of dissolved salts (3.5 106 kg y-1) is observed, which is partially explained by meteoric loading. The analysis also shows that an increase in the total alkalinity has occurred during the main drought phases of the last forty years, which has been shown to be consistent with what expected on the basis of the changes in the ionic composition of the waters. With decreasing water levels, a strong reduction in water transparency has also been observed, which does not appear to be connected with a change in the trophic state of the lake, but rather with the increase of suspended solids from bottom sediments, in agreement with the predictions based on resuspension models in shallow waters. On putting the results into the future scenario of climate change, an accelerating drought and progressive worsening of the water quality can be predicted for Lake Trasimeno in the near future.
Investigating uncertainty of climate change effect on entering runoff to Urmia Lake Iran  [PDF]
P. Razmara,A. R. Massah Bavani,H. Motiee,S. Torabi
Hydrology and Earth System Sciences Discussions , 2013, DOI: 10.5194/hessd-10-2183-2013
Abstract: The largest lake in Iran, Urmia Lake, has been faced with a sharp decline in water surface in recent years. This decline is putting the survival of Urmia Lake at risk. Due to the fact that the water surface of lakes is affected directly by the entering runoff, herein we study the effect of climate change on the runoff entering Urmia Lake. Ten climate models among AOGCM-AR4 models in the future time period 2013–2040 will be used, under the emission scenarios A2 and B1. The downscaling method used in this research is the change factor-LARS method, while for simulating the runoff, the artificial neural network was applied. First, both the 30-yr and monthly scenarios of climate change, temperature, and precipitation of the region were generated and weighted by the Beta function (β). Then, the cumulative density function (cdf) for each month was computed. Calculating the scenarios of climate change and precipitation at levels of 25, 50, and 75% of cdf functions, and introducing them into LARS-wg model, the time series of temperature and precipitation in the region in the future time period were computed considering the uncertainty of climate variability. Then, introducing the time series of temperature and precipitation at different risk levels into the artificial neural network, the future runoff was generated. The findings illustrate a decrease of streamflow into Urmia Lake in scenario A2 at the three risk levels 25, 50, and 75% by, respectively, 21, 13, and 0.3%, and an increase by, respectively, 4.7, 13.8, and 18.9% in scenario B1. Also, scenario A2 with its prediction of a warm and dry climate suggests more critical conditions for the future compared to scenario B1 and its cool, humid climate.
Cyanobacteria-/cyanotoxin-contaminations and eutrophication status before Wuxi Drinking Water Crisis in Lake Taihu, China

Yongmei Liu,Wei Chen,Dunhai Li,Zebo Huang,Yinwu Shen,Yongding Liu,

环境科学学报(英文版) , 2011,
Abstract: After the appalling "Wuxi Drinking Water Crisis", increasing investigations concerning the contaminations of cyanobacterial blooms and their toxins in Lake Taihu have been performed and reported in the last two years. However, information regarding these issues before the crisis in 2007 remained insufficient. To provide some background data for further comparisons, the present study reported our investigations conducted in 2004, associated with the cyanotoxin contaminations as well as the eutrophication status in Lake Taihu. Results from the one-year-study near a drinking water resource for Wuxi City indicated that, unlike the status in recent two years, cyanobacteria and chlorophyta are the co-dominance species throughout the year. The highest toxin concentration (34.2 ng/mL)in water columns occurred in August. In bloom biomass, the peak value of intracellular toxin (0.59 μg/mg DW) was determined in October, which was lag behind that in water column. In addition, MC-RR was the major toxin variant throughout the year. During the study period, nutrients levels of total nitrogen and phosphorus were also recorded monthly. Results from the present study will lead to a better understanding of the eutrophication status and the potential risks before "Wuxi Drinking Water Crisis".
Hydrogeochemistry of seasonal variation of Urmia Salt Lake, Iran
Samad Alipour
Aquatic Biosystems , 2006, DOI: 10.1186/1746-1448-2-9
Abstract: Seven hundred and four samples were taken and partially analyzed for the main cations and anions. Surface water (0.5 m. depth) was analyzed for Na, K, Mg, Ca, Br and Li, and averaged 87.118 g/lit, 1.48 g/lit, 4.82 g/lit, 4.54 g/lit, 1.19 ppm and 12.7 ppm respectively for the western half of the lake. Sodium ranged between 84 to 91.2 g/lit, and showed higher concentrations in the south than in the north. This unexpected result may be caused by shallower depth in the south and a higher net evaporation effect. Calcium ranged between 4.2 to 5 g/lit, apparently slightly higher in the north. K is higher in the south, possibly due to rivers entering from south that may carry slightly higher K in solution.In the middle-range samples (0.5–5 m.), K averaged 1.43 g/lit and ranged from 1.40 to 1.46 g/lit. At this intermediate depth the distribution of K is clearly higher to the south of the causeway that is currently under construction. It is not clear whether this increase is the effect of the causeway or the effect of the salty Aji-Chay River to the east, and the Khoy salt domes to the north of the lake. At depth (5 m–10 m), K averaged 1.48 g/lit and ranged from 1.4 to 1.49 g/lit, differing only in the second decimal from the average of the middle and surface samples.Ignoring the small difference between the averages of the three sample depths, the distribution of K is highly homogeneous in the lake water due to the mixing process. Therefore causeway construction has not yet strongly affected K distribution, or it may be at the starting point. Magnesium concentration ranged from 4.6 to 5-g/lit, and was elevated in the south. This differs somewhat compared to calcium. Lithium, with an average of 12–13 ppm, is slightly higher in the south, and has not shown any significant variation in all three seasons. Iodine was below the detection limit in the lake.Urmia Lake, geochemically, is highly uniform both to the south and north of the causeway, in both the surface and deep brines.
Analysis of Meteorological Factors of Forming Feculent and Anaerobic Water Aggregation Induced by Algal Bloom in Taihu Lake
太湖藻源性“湖泛”形成机制的气象因素分析

WANG Cheng-lin,ZHANG Yong,ZHANG Ning-hong,QIAN Xin,KONG Fan-xiang,
王成林
,张咏,张宁红,钱新,孔繁翔

环境科学 , 2011,
Abstract: The water quality pollution problem about feculent and anaerobic water aggregation (FAWA) induced by algal bloom in Taihu Lake, which is often called 'hufan' in Chinese, was studied. Its forming process is divided into 3 phases, i. e., material elements forming of FAWA, anaerobic products to be brought to the water surface and the maintaining of FAWA in the water surface. The conventional observational data from Wuxi meteorological station was analyzed. The result shows that there are similar meteorological characteristics of two FAWA phenomena in Taihu Lake in May, 2007 and May, 2008. A numerical simulation was performed to prove the analysis results. It indicates that propitious meteorological condition is one of the necessary forming factors of FAWA, which provides thermal and dynamical environment for FAWA. During the first phase, the weather conditions, such as high air temperature, gentle breeze and nearly invariable wind direction, maintain for more than 3 days and cause algal bloom to aggregate, then die, sink and anaerobic decay near lake bank. All these provide the precondition for FAWA. During the second phase, when the cold air mass passes across the Taihu basin, almost counter-direction wind, which maintains for more than 1 day with higher speed and lower air temperature, makes anaerobic products to be brought to the water surface by uplifted current. This is the trigger mechanism of FAWA. During the last phase, continual high air temperature and gentle breeze is favorable for FAWA in the water surface. Because meteorological factors are predictable, this research provides a way and basis for the further study of warning and controlling approaches of FAWA.
Investigation of correlation of the variations in land subsidence (detected by continuous GPS measurements) and methodological data in the surrounding areas of Lake Urmia  [PDF]
K. Moghtased-Azar,A. Mirzaei,H. R. Nankali,F. Tavakoli
Nonlinear Processes in Geophysics (NPG) , 2012, DOI: 10.5194/npg-19-675-2012
Abstract: Lake Urmia, a salt lake in the north-west of Iran, plays a valuable role in the environment, wildlife and economy of Iran and the region, but now faces great challenges for survival. The Lake is in immediate and great danger and is rapidly going to become barren desert. As a result, the increasing demands upon groundwater resources due to expanding metropolitan and agricultural areas are a serious challenge in the surrounding regions of Lake Urmia. The continuous GPS measurements around the lake illustrate significant subsidence rate between 2005 and 2009. The objective of this study was to detect and specify the non-linear correlation of land subsidence and temperature activities in the region from 2005 to 2009. For this purpose, the cross wavelet transform (XWT) was carried out between the two types of time series, namely vertical components of GPS measurements and daily temperature time series. The significant common patterns are illustrated in the high period bands from 180–218 days band (~6–7 months) from September 2007 to February 2009. Consequently, the satellite altimetry data confirmed that the maximum rate of linear trend of water variation in the lake from 2005 to 2009, is associated with time interval from September 2007 to February 2009. This event was detected by XWT as a critical interval to be holding the strong correlation between the land subsidence phenomena and surface temperature. Eventually the analysis can be used for modeling and prediction purposes and probably stave off the damage from subsidence phenomena.
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