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Showing 9 results for Urmia Lake


Volume 0, Issue 2 (8-2011)
Abstract

Urmia Lake and its surroundng wetlands have been severely affected by recent droughts (1998–2003) and a considerable decrease in inflow has affected lake ecosystem components. Integrated ecosystem-based management is a useful managing tool for the wise use and biodiversity conservation of wetlands. In the process of developing an integrated ecosystem-based management model for Urmia Lake, the identification of key stakeholders is of primary importance. In this research, stakeholder analysis is used as an effective tool for establishing collaborative management in the Urmia Lake catchment in terms of the following parameters and objectives: almost all stakeholders receive multiple benefits from Urmia Lake, either directly or indirectly; almost all stakeholders also cause impacts on the lake ecosystem, many of which result from activities that take place in areas located within in the Urmia catchment but far from the lake. In general, the stakeholders who receive the most benefits seem to cause the lowest impact (for example, Environmental groups), while those who receive fewer benefits may have larger impacts (for example, water resource managers). Recognizing that all stakeholders affect the lake in one way or another is an important concept that promotes the ethic that future management of the Lake should regarded as a shared responsibility between all stakeholders.

Volume 2, Issue 1 (9-2011)
Abstract

Abstract: In recent years, extension of Artemia applications in aquaculture and decreasing of natural resource, lead many of related studies to the distribution of Artemia population and new resource assessment studies. Urmia Lake as one the biggest habitat for Artemia because of ecological variations in the regions in which of its differentiations in cyst biometry and Artemia, moreover some genetic variations suggested to have some several Artemia populations in the Lake. In this project Artemia cyst samples were collected from 5 ecological stations of the Lake Urmia. The cyst hatching and the nauplii breeding up to adult Artemia stage were done according to optimum conditions in laboratory. Growth rate and survival of larva in days of 3, 5, 7, 11, 15, 20 of rearing period were measured in feeding with a complex of Dunaliella tertiolecta and Lanzy PZ for a period of 20 days in 75 and 150 ppt. Data and its statistical analysis revealed that according to previously records the growth rate of the Artemia was influenced by increasing the salinity from 75 to 150 ppt survival and growth rate of Artemia have been influenced by water salinity (P<0.05) but increasing the salinity only in two population of Bari and Eslami led decreasing of survival. The produced cysts in two salinity showed that Artemia population can produce the cysts with different diameter and there were not any statistic correlations between the salinity and populations. The Dandrogarm of population statistic analysis emphasized that according to growth rate and survival parameters and among populations under this test there were 4 different populations of Artemia urmiana in which had interesting differentiations in growth rate and survival. Keywords: Artemia, Survival, Growth rate, Salinity, Urmia Lake.

Volume 12, Issue 1 (6-2008)
Abstract

Urmia lake is located in the north-west of Iran and is recognized in the world as a largest habitat for Artemia. The last decade drought episodes and recent dam construction programs have simultaneously caused more evaporation of the lake water and thus considerable variations of water surface levels. The main aim of the present study was to map of Urmia lake water surface changes on a seasonal, periodical and over long-term scales. For this purpose, some different types of multi-scanner, spectral and temporal images (MSS, TM, ETM+, IRS-1C, MODIS and TOPEX/Jason data observing from 1976 to 2005) were processed to generate most of the thematic models in spatial and temporal contexts. First, to choose a number of referred images captured, some ground-based observation data and the obtained information from TOPEX/Jason satellites were analyzed. Then based on the available archived imageries, all the multi-date satellite data were chosen and progressively geo-referenced and then geo-rectified by ERDAS Imagine software package based on the reference ground control points. Subsequently, all the time series images were analyzed to derive some pre-defined segmented Classes such as water surface categories and shorelines changes. The revealed models demonstrated several seasonal persuaded fluctuations and considerable periodical change on the Urmia Lake coastlines particulaarly during the last decade. These great variations have occurred as the result of 3.5 meters decrease in the height of water in the lake and about 23 percent decreasing of water surface during the past 30 years. This has successively caused a diminishing of shorelines particularly on the southeast and east coasts of the Urmia Lake, changing landcover and landuse types by depletion of significant wetlands. Implementation of such significant changes illustrated that the majority of local biotic and biotic components all over the surrounding areas and inner islands, would be in crucial threat in the near future.

Volume 12, Issue 1 (4-2024)
Abstract

Aim Urmia Lake Restoration Headquarters has carried out actions since its establishment until now, and there are disagreements between supporters and opponents about its outputs. For this purpose, in the year 2021, this research was conducted to evaluate the environmental effectiveness of the actions of rehabilitation headquarters from the point of view of local communities. Materials & Methods an applied and fundamental research was done to reach the study golds. . In terms of method, regarding to the nature of the subject and research objectives, the descriptive-analytical and survey method (survey of local communities) has been used. The tool for collecting information and data was a researcher-made questionnaire that was randomly filled through interviews with residents. Findings The results showed that different actions have significant differences in terms of respondents' satisfaction, so the highest level of satisfaction, with a value of 2.89, is related to the non-living windbreak, and the lowest level is related to the Poly -Shrub Planting with the value of 1.67. Conclusion In general, despite the relative success of the actions of the rehabilitation headquarters, these actions have not been full effective in the proper management of surface and subsurface water resources, the modification of the cultivation pattern, and the prevention of the spread of soil salinity in agricultural lands. Therefore, to prevent the environmental disaster and its destructive consequences, it is suggested to take urgent action to save Urmia Lake by using all local and international capacities.

Volume 17, Issue 2 (7-2017)
Abstract

Scientific method for correct recognition and understanding of the hydrologic phenomena is investigation of their simple models. Generally, a model is a simple representation of a complex system. In mathematical models, behavior of the system is described by a series of mathematical equations, along with logical relationships between variables and parameters. Despite the various proposed mathematical models for modeling of the hydrologic phenomena, there is not a unique approach in this respect. This might be due to spatial and temporal variability of hydrologic phenomena and also lack of mathematical tools for extraction of proper structure for these phenomena. These variations are the result of dependability of the phenomena on different components. This problem has caused the past researches on hydrologic modeling to view the situation as random and probabilistic. The performance of most natural phenomena, including hydrologic problems, in short time scales, to be viewed as completely random and without any trend. But, with a change in time scale, and using sophisticated models, a type of interval and order will be observed. Nowadays, researchers believe that hydrologic phenomena, which have dynamic and nonlinear nature, could be better analyzed by nonlinear and deterministic chaotic models. Hydrologic components in lakes have non-linear and dynamic nature. But, since the changes that these components create in the lakes don’t happen suddenly, it is possible to study and predict some of these elements in the hydrologic cycle. Nowadays, with the evolution of computer models, it is believed that analysis, modeling and control of complex natural phenomena, including hydrologic processes, could be better performed with chaotic models than probabilistic models. Studying the hydrologic components in analysis of the water resources systems, such as lakes, is very important in their quantitative and qualitative operation and management. Due to the importance of precipitation in variations of water level in Urmia Lake, located in north-western Iran, the chaos theory could be a powerful approach to analyze and model the complex behavior of such phenomena. Investigation of chaotic or random behavior of rainfall time series in the lake, for the choice of the best suited rainfall simulation approach, is an important and controversial issue that has been dealt with in this research. First, using the correlation dimension method (CDM), the monthly rainfall time series of Urmia Lake was analyzed over a period of 40 years (1967-2007). After calculating the delay time using average mutual information (AMI) and also calculation of the embedding dimension using false nearest neighbor (FNN) algorithm, the phase space was reconstructed and then the correlation dimension was determined. Then, by using Lyapunof exponent and Fourier power spectrum, the existence of chaos was investigated. Results revealed that presence of chaos in the rainfall time series of Urmia Lake is evident with the non-integer CDM of 2.56, positive value of Lyapunof exponent (maximum of about 2.5) and broad band Fourier power spectrum. Consequently, the system behavior is regular; in other words, the system is not considered random. In such a system, chaos theory has the ability to extract short-term time series from long-term records. In addition, the existence of low-dimensional chaos implies the possibility of accurate short-term predictions of precipitation.

Volume 20, Issue 3 (11-2016)
Abstract

Recently, environmental change is a main concern in sustainable science. That can be affected human society in the global, national, regional and local scale. According to the sustainability paradigm, the relationship between human and environmental system is a global discourse. Global environmental change research has seen increased attention to the concept of vulnerability. In this sense, environmental change as a characteristic of social-ecological systems linked to resilience. In the recent years Urmia Lake ecosystem has been effected by many drivers (climate change, dam construction, irrigated farm land expanse and irregular utilization of groundwater). Therefore, the main aim of this paper is identification of vulnerable spheres and nods on the Urmia Lake eastern spatial organization. In this paper we used social, economic and physical index for identification and determination of vulnerability ecosystem change. We used multi attribute decision making GIS- based for ordering the vulnerability spheres. Moreover, the chosen model of multi attribute decision making was TOPSIS. According to the result, the most vulnerable spheres are in Azarshar, Ajabshir and Bonab counties. This paper also indicates the most rural population density is in Bonab, Malekan and Ajabshir counties which main activity of these regions is agriculture. Hence, rural settlements of aforementioned counties are in the serious threat with minimum distance of Urmia Lake.  

Volume 22, Issue 4 (10-2019)
Abstract

Aims: The present study was aimed to investigate isolation and identification of halophil bacteria producing asparaginase from Urmia Lake and the effect of different salt concentrations and temperature on asparaginase production.
Materials & Methods: The water and mud samples from Urmia Lake were cultivated in MH and SWN media for isolation of halotolerant bacteria. Then, the asparaginase production rate was investigated in saline M9. The asparaginase production rate by isolates was investigated in different salt concentrations (10, 20, 30, and 40%) and temperatures (30, 35, 37, 45, and 50°C). Two isolates with a high production rate of asparaginase were stained by gram stain method and were identified by 16S rRNA sequencing.
Findings: In the present study, 57 isolates were obtained which 10 isolates showed asparaginase production. Among these, 2 isolates (A2 and A3) were selected as superior isolates. The isolate A3 has shown the largest halo (54mm) at 35°C and 10% salt concentration. Moreover, the isolate A2 has shown the largest halo (56mm) at 35°C and 40% salt concentration. The 16SrRNA sequencing showed that the A2 isolate was similar 98.9% to the Halomonas elongata strain, and the A3 isolate was similar 100% to the Bacillus aryabhattai strain.
Conclusion: The bacteria isolated from Urmia Lake are potential source of asparaginase enzyme. H. elongate and B. aryabhattai strains isolated from Urmia Lake can be used to production of asparaginase without side effects for cancer patients.

Ali Binandeh, Behruz Khanmohamadi, Kumars Hajimohamadi,
Volume 24, Issue 3 (9-2017)
Abstract

Bari Castle is located on the western side of Urmia Lake. The castle enclosed with stony walls measuring several meters high, encompasses a widespread area. It was used in the first millennium BC considering the castle’s architectural features and potsherd remains found on its surface. For almost 150 years, from the middle of the 9th century to the end of the 8th century, the Urartian areas in Iran did not witness any attack from Assyrians. It was only during the reign of Sargon II, clashes erupted between Urartu and Assyria. The reason was that Urartu interfered more and more in the affairs of the kingdom of Mannea, which Assyria considered a tributary. The first half of the 7th century is when Mannaean seized the power in that area. It was the time which saw the expansion of Mannean more than ever, especially its dominance on the Urmia plain, hence; the Bari castle was of the Mannaean Empire.

Volume 24, Issue 3 (10-2020)
Abstract

Extended abstract
Introduction
Land use is one of the most important biophysical and socio-economic characteristics in any watershed. The science of land change has recently been introduced as one of the fundamental components of global environmental change and sustainable development research. Monitoring land changes is important in future planning and natural resource management. Therefore, the need to detect such changes in an ecosystem is very important. Therefore, the need to detect such changes in an ecosystem is very important to take appropriate action if necessary. . Due to the fact that Lake Urmia is an important ecotourism center in Azerbaijan, with the drying up of the lake, Greater Azerbaijan and all the areas affected by this phenomenon will face a recession of domestic tourists. These factors, in turn, will lead to the migration of residents of the villages of this region to the surrounding cities and social problems in these cities. Its catchment area has been one of the water resources of this area[r11] . But the extent to which these changes, and especially the change in land use, have taken place, requires special study. In general, it is possible to study land use changes in both terrestrial and remote sensing methods. However, in recent decades, with the development of hardware and software facilities for processing satellite images, as well as the ease of access to multi-spectral and ultraviolet images, the use of remote sensing techniques to produce land use maps has become more common. The use of remote sensing technology has a special place in natural resource studies. Multi-time comparison, information updates, digital processing, data diversity, and data transfer speeds have made remote sensing the most important technology in detecting changes.
Methodology
The approach of the present study is developmental-applied and its descriptive-analytical method. According to the subject of the research and in line with the objectives defined in this research, satellite image with the specifications listed in Table (1) and the softwares of Google Earth, ENVI4.8, ArcGIS10.2 have been used. To use satellite imagery to perform techniques, all images must have the same coordinates. Remote sensing techniques, especially those used to classify land use and detect changes, are usually monitored and analyzed based on similar pixels in multi-time images; Corrections, images are not properly geometrically and radiometrically corrected, research accuracy is reduced. Thus, the satellite images of 1989, 2000, 2016, and 2019 were returned to the image with an RMS error of 0.42 pixels, capturing 20 control points from the image surface to the image method. In geometric correction, the ground control points were tried to have a good distribution at the image level so that the mathematical model used to calculate the unknown coefficients in the equation would have less error. To convert the corrected image coordinates to the non-corrected image, a second-order function was used. . In this study, the numerical value reduction method of dark pixels for radiometric correction of images has been used. In this method, a constant value of the total value of the pixels in a given band is reduced to apply radiometric corrections to each satellite image. In the next step, the images were mosaic due to the location of the study area in two women (1368-348)[r12] . Then, using field visits and the global location apparatus, instructional samples for each use (lake, agriculture, salt marsh, other lands) were identified in the study area.
Results and discussion
In this study, three supervised classification methods (neural network, backup vector machine and maximum probability) have been used to extract land use maps. By comparing the accuracy of the classification obtained from the methods mentioned in Table (2), it was found that the classification method of the backing vector machine with a cap rate of 99.75% is more accurate than other methods. According to the results of both classification methods of machine vector support and neural network, precise methods for extracting land uses and in separating the phenomena that have close spectral behavior are very successful, especially support vector machine  , which . Which was a bit successful.[r13] 
Conclusion
In this study, first, images of measuring satellites (MSS-TM-OLI) were used and the map of Urmia Lake, lake landscaping and its surroundings were was extracted by applying supervised classification (support vector machine, neural network and maximum probability). . Comparison of image stratification methods showed that the support vector machine method has more classification accuracy than the other two methods due to its general accuracy and higher capability coefficient. The results also show that satellite imagery has a significant ability to extract land uses. Also, in order to investigate the trend of land use change, maps extracted from satellite imagery in 1989, 2000, 2016 and 2019 were compared. Examination of land use maps in the three mentioned periods showed significant changes in land cover. These changes include: Agricultural land use area has increased significantly from 1989 to 2019 due to the favorable area for agriculture and drilling wells. Numerous and the use of aquifers has been underground . Analysis of Landsat satellite images showed that significant fluctuations in the lake's water level have occurred over the years. So so that the water level changes of Urmia Lake from 1989 to 2016 have increased from 5348 to about 2705 square kilometers. However, from 2016 to 2019, due to heavy cross-sectional rains, it had an increase in water area of ​​1644 square kilometers. The images also show that the coastline, especially in the east and southeast of the study area, has a significant number of boys. From 1989 to 2000, the area of ​​this land use increased by 378 square kilometers. Also, between 2000 and 2016, its area continued to rise and increased to 786 square kilometers. However, due to the increase in cross-sectional rainfall during 2016 to 2019, the water level of the lake has increased and some of the salt marshes have been submerged and the land use area of ​​the salt marshes has decreased by 838 square kilometers.



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