جستجوی مقالات مرتبط با کلیدواژه « دریاچه ارومیه » در نشریات گروه « اکولوژی »

One of the semi-distributed models that has been considered by researchers in the last decade is the hydrological model of variable infiltration capacity (VIC). The study aim was evaluating the efficiency of VIC model in simulated runoff and flow of rivers in Urmia city overlooking Lake Urmia, including Nazlochyi, Rozeh Chay, Shahrchay and Barandozchay. ERA5 meteorological data was used to achieve this goal. The indices used in the present study to validate the rainfall input data include (R2, TRMSE, NSE). The results of satellite meteorological data surveys with observational data have acceptable results. More precisely, the probability index of POD detection in all stations in the region is above %80. The Khoy synoptic station in the north of the study area is more than %95. Also, the correlation between maximum and minimum temperature data is above %93. After forming the hydrological and mathematical model of the area, the calibration of the observed runoff of the sub-basins with the runoff simulated by the VIC model was investigated. The surveying showed that in all major rivers in the region, the NSE value was above %72 and the R2 coefficient of all basins was more than %64. Also, for validation between observational and simulated data, the maximum flow rate (2010-2000) was used and the results showed that the model was more accurate in simulating maximum runoff, so that the NSE coefficient in the Nazlochay basin was %80 and the coefficient R2 was %78 for daily observational data.

This study was performed to find halophilic bacteria that have the ability to increase salinity resistance in wheat seedlings, so that any type of wheat cultivar can be grown in saline areas by inoculation with these bacteria without the need for genetic manipulation.A number of highly saline farm soils from several areas around Tabriz and Urmia Lake were screened to isolate bacterial isolates. A total of six highly halophilic isolates were isolated for the study. The effect of bacteria on salinity tolerance in wheat was determined as a factorial of two factors (salinity and bacteria) based on a randomized complete block design with three replications. The effect of six bacterial isolates at three high concentrations of salt (NaCl) (0.5, 1 and 1.5%) on wheat seed growth under standard laboratory conditions for four weeks was evaluated. Two bacterial isolates that had the best performance - in most growth indices such as fresh and dry size and weight of roots and stems - were selected and their effect was assayed under greenhouse conditions. Finally, the best bacteria in terms of function were selected and identified by molecular methodsFrom the six highly halophilic bacterial isolates, two bacteria were selected for greenhouse studies, one of which, caused a 50% increase in most growth factors, was selected for identification. Molecular identification based on barcoding 16S rDNA region showed that this bacterium belongs to Oceanbacillus picturae with 99% probability.This is the first report of the presence of Oceanbacillus picturae in the soils of

Phytoplankton is one of the main components of wetlands, which plays a vital role in providing nutrients, oxygen for other organisms, stabilizing nitrogen and carbon dioxide. In the meantime, the current status of Lake Urmia highlights the need to conserve and protect wetlands related to these ecosystems and their living and non-living components. Therefore, this study was conducted to assist in the restoration of Lake Urmia by monitoring the hydrobiological status of Solduz wetland. Field surveys and sampling of Solduz Wetland were carried out from 6 stations in summer and winter of 2016. Sampling was performed using a vertical rotor with a diameter of 10 cm. The effects of physicochemical factors and temporal variations on the diversity, abundance and biological characteristics of phytoplankton in the ecosystem were investigated. In total, 49 phytoplankton species were identified from the Solduz wetland: 17 species belonging to green algae, 16 species belonging to diatoms and 9 species belonging to cyanobacteria and some others species. The results of this study showed the presence/absence of the mentioned algae may be caused by changes in the physicochemical especially temperature, nitrate, phosphate, pH and electrical conductivity which occur naturally in different seasons. So that the population density index and biodiversity indices such as species richness, species diversity and dominance was observed in the warm season more than the cold season. The results of this study can assist executive managers in Urmia Lake monitoring plans for better management and utilization of related wetlands of Lake Urmia.

The purpose of this study is to determine the areas with groundwater potential using artificial neural network (ANN), random forest (RF), support vector machine (SVM) and linear regression (GLM) models. In the present study, 14 parameters groundwater potential including altitude, slope, slope direction, curvature, distance to stream and fault, stream and fault density, lithology, average rainfall, land use, topographic position index (TPI), relative slope position (RSP) and topographic wetness index (TWI) were used. From a total of 10,624 springs, randomly 70% as test data and 30% as validation data were classified. The RF model was also used to determine the most important parameters. Alignment test between parameters was performed using SPSS software. The Receiver operating characteristic was used to Predictive power of models and the Seed Cell Area Indexes (SCAI) was used to accurately distinguish between classes. The results showed that there is no alignment between the parameters. The results of RF model showed that the parameters of height, land use, slope, and distance from fault, TWI and lithology are the most important factors affecting groundwater potential, respectively. Also, based on the ROC curve in both training (0.915) and validation (0.909), the ANN model had the highest accuracy and the RF, SVM and GLM models were in the next categories. Also, the results of the seed cell area index showed that all four models have separated the classes with appropriate accuracy. According to the ANN model, 31.4% of the basin has high and very high groundwater potential.

Lake Urmia is one of the most important and valuable Iranian ecosystems. Given that a large population of East Azarbaijan residents in the Urmia Lake Basin is engaged in agricultural business, and the economy of the region and residents of this region depend on the sustainability of agricultural systems in the present and future, hence the study of the sustainability of the agricultural ecosystems of this region are very important.

This paper examines the sustainability of the agricultural ecosystems of Azarshahr in the period of 2004-2017. The weight of the indicators was determined using entropy method and other information was collected from Jihad-e-Agriculture Organization, Regional Water Organization and the yearbooks of East Azarbaijan province during the studied years.

The results of the study showed that the level of stability at the beginning of the period was decreasing during the years 2004-2006 and after a temporary increase in the years 2006-2013, it was reduced again and the conditions of sustainability deteriorated.

Given the results of weighting the indices and calculating the sustainability level, the important role of the factors of sustainability, especially the use of chemical inputs, was shown on the sustainability.

Environmental rights, laws and regulations are among the most important tools for protecting and managing natural resources. In this context, it should be noted that by implementing environmental laws, it cannot expect to solve all the biological problems; because, other elements such as the awareness of the people and the institutionalization of this category in culture and social behaviors are very important and effective. On the other hand, environmental laws, due to ambiguity, have not had a satisfactory performance in the field of environmental impacts. However, preventing pollution and destroying the environment and regulating human-environmental relations without binding legal rules will not be possible. Accordingly, some current laws and regulations, due to changes in the environment of the country and the promotion of human knowledge of the values and functions of natural resources, need to be reviewed and reformed. Wetlands and lakes such as Lake Urmia are valuable natural resources that are essential for a country with a climate of Iran, which requires a variety of policy tools. Therefore, in this study, in addition to describe Iran’s 50 years old environmental legal clauses during 1986-2018, that are directly and indirectly related to the wetland in the laws and regulations of the country, the status of its support and management in upstream documents is also discussed. The regulations and related instructions will also be reviewed. In addition, using the results of studies and analyses carried out in the context of existing laws in the field of natural ecosystems, the legal, structural, social, economic and cultural challenges of the laws of conservation Wetlands including Lake Urmia will also is addressed. The results of this study indicate that although laws and regulations play an important role in the conservation and management of natural resources, they do not have the needed efficiency individually. Therefore, in order to achieve the goals of the legislator, it is necessary to consider the economic approaches and tools, based on market incentives and price mechanisms, simultaneously with the legal instruments with less flexibility. Also, the concept of reasonable use of wetlands and lakes needs to be revised in the national policies, laws and legal cases which are contrary to their reasonable use. Besides, the native conditions and characteristics of each wetland and lakes need to be considered in their developing protective and managerial rules and regulations. Accordingly, the setting of unique environmental approaches and standards for management and protection can play an effective role in improving the performance and efficiency of laws and standards in the field of implementation as well as in preventing environmental consequences.

Sustainability is considered as an effective framework for managing rural areas against a variety of environmental hazards, including droughts, which require the use of sustainable sustainability techniques. The purpose of this study was to assess the stability of the villages of Qaleh Chaie watershed in Ajabshir city against the drying of Lake Urmia. The research was applied and the information gathering method was library and field research. The statistical population of the study is 21185 people living in 21 villages in this area. The sample size was 380 using Cochran formula and was selected by simple random sampling method. The findings of the study, using the Barometric Model of Sustainability, showed that the environmental sustainability of the villages in the years 2005 to 2017 was exposed with a sustained reduction of -0.146. From the viewpoint of social sustainability and economic sustainability, they experienced a relative increase of 0.132 and 0.055 respectively. Finally, the Javan Qaleh village with a sustainability level of 0.742 has been the most stable village over the past 15 years and then the villages of Qajuldeh (0.666) and Yengeje (0.657) are located. Also, the villages of Chenar, Mahmoudabad and Gonbad have been the most volatile villages in the last 15 years. Also, Kendall's findings showed that there is a positive and significant correlation between the location of villages in Lake Urmia in terms of distance and proximity to their sustainability level at the level of r = 0.577.

Wind speed is one of the most complex meteorological parameters in a specific region Furthermore, climate behavior in an area is influenced temporally in short and long terms. In the present study, Mann-Kendall and Petit nonparametric tests were applied to analyze the trend of monthly and annually wind speed data series in four synoptic stations of Lake Urmia (Tabriz, Urmia stations with 50 years, Mahabad and Sahand with 28 years). The results of the aforementioned tests, based on annual and montly scales, showed that the average wind speed at all stations has an increasing trend at 99% confidence level. However, the concerned years were not appeared to be quite identical in all stations. These changes occurred at Mahabad station in 2000 and at other stations in 1995. Also, the wind speed increased at Mahabad station in winter and at other stations in spring and summer.

Lake Urmia, despite its unique environmental characteristics, has been exposed to drying as a result of the interference of natural and human factors, and contrary to the role it could play in reducing the environmental conditions of the region, the Lake Urmia threatens the health of the people and the loss of their basic rights to life,including the right to clean air,the optional choice of residence, etc. In spite of these problems, what is necessary is the consideration of the fundamental question of how can we use the jurisprudential foundations to justify the right to the environment of Lake Urmia? Where is the rule of “Lazarar” as one of the indisputable rules of jurisprudence in proving this right,and can this rule be used in cases where the absence of an affair or quitting can cause harm?
The current paper, understanding this necessity,explores the concept of the right to the environment and the concept of the Lazarar principle,and has tried to clarify the relation between these two concepts, to clarify the position of the argumentative principle in proving the environmental rights of Lake Urmia,and in this way, to provide strategies for protecting the lake and providing environmental protection around it.

Urmia Lake is one of the biggest over-saturated salt lakes of the world. It is located at the northwestern part of Iran. The temporal change in the concentration of Artemia fecal pellets can be used as an indicator of lake level changes, paleoclimate and therefore regional hydrological changes. In this study basis on the previous data collection, 28 sedimentary intact cores with a maximum depth of 10 meters and a total of more than 200 meters were sampled from the lake sediments by Gouge Auger coring method. Sedimentary facies were separated based on color, grain size, existence of Artemia fecal pellets, sedimentary fabrics and the type of evaporative minerals. With regard to vertical sedimentary facies (from surface to sub-surface areas) changes and the results of elemental analysis, geography, climatic conditions and lake water level fluctuation were re-constructed. Facies belong to Lake, Lagoon, River and Playa environments. According to the age measurement by isotope carbon-14 method, deposition rate is between 0.7 to 0.8 mm per year, but this rate was varied in different parts of the lake (1.0 to 1 mm per year), this amount was maximum in river delta (mostly west of lake). Artemia fecal pellets constitute about 5-35% in average and 90% in maximum of the deposits. Fecal pellets of Artemia that formed of aragonite prismes were one of the biochemical sediments of the lake that mostly intact pellets or crushed cream color and black pyrite pellets are observed. Finding Artemia fecal pellets as old as early Holocene, showing that this Crustacean lived in the lake since at least the beginning of the Holocene. Sediments study shows that the organic content of fecal pellets gradually diminishes down the cores. Increase in amount of fecal pellets was match with wet interglacial periods in South Asia and Africa (4 to 10 thousand years ago). These periods also shows wet conditions with sediment geochemistry studies. The Urmia lake level fluctuations can be a major factor in controlling the high temporal variations in the abundance of Artemia fecal pellets. However, caution should be taken in the interpretations as other environmental factors, such as temperature changes, water circulation, taphonomic history, etc.