Water level decline at Iran's Lake Urmia: changing population dynamics

2021 ◽  
pp. 1-20
Author(s):  
Somayeh Mohammadi hamidi ◽  
Hossein Nazmfar ◽  
Christine Fürst ◽  
Mohammad Hassan Yazdani ◽  
Ahad Rezayan
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Stephan Schulz ◽  
Sahand Darehshouri ◽  
Elmira Hassanzadeh ◽  
Massoud Tajrishy ◽  
Christoph Schüth

2020 ◽  
Author(s):  
Sahand Darehshouri ◽  
Nils Michelsen ◽  
Christoph Schüth ◽  
Stephan Schulz

<p>Lake Urmia, located in the northwest of Iran, had an initial volume of about 19 km<sup>3</sup> and a surface area of 5,700 km<sup>2</sup> (Alipour, 2006). Once one of the largest hypersaline lakes in the world, this UNESCO Biosphere Reserve site currently shows a remarkable water level decline. About 70% of the lake area (Tourian et al., 2015) and more than 90% of its volume were lost between 2000 and 2014 (Schulz et al., 2020). The lack of a precise water balance of the Lake Urmia catchment is one of the challenges authorities are facing in their efforts to restore the lake to its ecological level. Here, key issues are that lake evaporation rates are mostly assumed and that evaporation of shallow groundwater from dried-up areas (up to 3,000 km<sup>2</sup>) is often ignored. The objective of this study is to obtain evaporation rate estimates for the dried-up parts of the Urmia lake bed. To this end, we set up a laboratory experiment with undisturbed soil columns collected from dried-up areas of the lake. With the help of a custom-made low-cost environmental chamber, the columns were subject to day- and night-time weather conditions typical for the area. Performed measurements comprise water level logging and monitoring of mass losses from the columns due to evaporation. First experimental results will be presented.</p><p> </p><p><strong>References </strong></p><p>Alipour, S., 2006. Hydrogeochemistry of seasonal variation of Urmia Salt Lake, Iran. Saline Systems 2, 9. doi:10.1186/1746-1448-2-9</p><p>Schulz, S., Darehshouri, S., Hassanzadeh, E., Tajrishy, M., Schüth, C., 2020. Climate change or irrigated agriculture – what drives the water level decline of Lake Urmia. Sci. Rep. 1–10. doi:10.1038/s41598-019-57150-y</p><p>Tourian, M.J., Elmi, O., Chen, Q., Devaraju, B., Roohi, S., Sneeuw, N., 2015. A spaceborne multisensor approach to monitor the desiccation of Lake Urmia in Iran. Remote Sens. Environ. 156, 349–360. doi:10.1016/j.rse.2014.10.006</p><p> </p>


2020 ◽  
Author(s):  
Stephan Schulz ◽  
Sahand Darehshouri ◽  
Elmira Hassanzadeh ◽  
Christoph Schüth

<p>Lake Urmia is one of the largest hypersaline lakes on earth with a unique biodiversity. Over the past two decades the lake water level declined dramatically, threatening the functionality of the lake’s ecosystems. There is a controversial debate about the reasons for this decline, with either mismanagement of the water resources, or climatic changes assumed to be the main cause.</p><p>During this study we gathered an extensive hydro-meteorological data set, information about the reservoirs and the lake bathymetry. This data served for a quantification of the water budget components of Lake Urmia over the last five decades. Interestingly, a comparison of the temporal patterns of the principal natural boundary conditions of streamflow (precipitation and evaporation) with the inflow to the lake revealed that the variability of the inflow can be well explained its natural drivers. With this we can show that variations of Lake Urmia’s water level during the analyzed period were mainly triggered by climatic changes.</p><p>However, under the current climatic conditions agricultural water extraction volumes are significant and often exceed the remaining surface water inflow volumes. This rather simple observation shows that something deeper needs to be dug here. Therefore, we performed a parsimonious hindcast experiment and run a set of development scenarios based on the previously developed water balance. This helped us to better quantify the human impact on the development of the water volume of Lake Urmia. We could show that changes in agricultural water withdrawal would have a significant impact on the lake volume and could either stabilize the lake, or lead to its complete collapse (Schulz et al., 2020).</p><p> </p><p><strong>References</strong></p><p>Schulz, S., Darehshouri, S., Hassanzadeh, E., Tajrishy, M. and Schüth, C.: Climate change or irrigated agriculture – what drives the water level decline of Lake Urmia, Sci. Rep., 10(1), 236, doi:10.1038/s41598-019-57150-y, 2020.</p>


2020 ◽  
Author(s):  
Ehsan Foroumandi ◽  
Vahid Nourani ◽  
Elnaz Sharghi

Abstract Lake Urmia, as the largest lake in Iran, has suffered from water-level decline and this problem needs to be investigated accurately. The major reason for the decline is controversial. The current paper aimed to study the hydro-environmental variables over the Lake Urmia basin using remote sensing tools, artificial neural networks, wavelet transforms, and Mann–Kendall trend tests from 1995 to 2019 in order to determine the primary reason of the decline and to find the most important hydrologic periodicities over the basin. The results indicated that for the monthly-, seasonally-, and annually-based time series, the components with 4-month and 16-month, 24- and 48-month, and 2- and 4-year, respectively, are the most dominant periodicities over the basin. The agricultural increase according to the vegetation index and evapotranspiration and their close relationship with the water-level change indicated that human land-use is the main reason for the decline. The increasing agriculture, in the situations that the precipitation has not increased, caused the inflow runoff to the lake to decline and the remaining smaller discharge is not sufficient to stabilize the water level. Temperature time series, also, has experienced a significant positive trend which intensified the water-level change.


2009 ◽  
Vol 57 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Linda Olsvig-Whittaker ◽  
Margareta Walczak ◽  
Amos Sabach ◽  
Eli Dror

PLoS ONE ◽  
2012 ◽  
Vol 7 (7) ◽  
pp. e39067 ◽  
Author(s):  
Jason A. L. Jeffery ◽  
Archie C. A. Clements ◽  
Yen Thi Nguyen ◽  
Le Hoang Nguyen ◽  
Son Hai Tran ◽  
...  

2010 ◽  
Vol 160-162 ◽  
pp. 750-755
Author(s):  
Yu Kun Zhao ◽  
Ji Hong Yang ◽  
Qing An Li

Rapid drawdown of water level is one of the most important factors that influencing the embankment stability. Based on the principle of geomechanical model test and hydroaulic model test methods, the model test was performed to study Yellow River downstream embankment instability induced by rapid drawdown of water level. The slope models with geometric scale of 1:25, 1:45, 1:62.5 were constructed in the transparent plexiglass model box with 1.6m long, 0.8m wide and 0.6m high. Changes on the slope were recorded during water level decline at different velocity by digital camera and slope tracer etc. The model test results showed that during the rapid drawdown process, there was only small cracks and not slippage in advance; when the water level dropped to a certain height, the sliding distance increased suddenly, which showed that the rate of water level decline was behind the river water, and the slope weight and downslope hydrodynamic pressure by the saturation line in slope body were higher than water lever exceeds the sliding force in a very short period of time, which caused landslide; after the sliding body appearing, slide was continuous and not mutation.


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