f. asadzadeh

It is necessary to optimize the use of water resources and nitrogen fertilizers through proper planing and management to increase economic efficiency while saving inputs , without significantly affecting  riceyield. This study investigates the physical and economic productivity of water and nitrogen in three rice varieties under different irrigation and nitrogen fertilizer treatments. The experiment was conducted using a split- plot design based on a randomized complete block design with three replications over three years at the Rice Research Institute of Iran located in Guilan Province, RashtCounty . The main factor in this experiment was irrigation management at four levels: flood irrigation (I1) and alternate irrigation treatments (I2, I3, and I4),with irrigation intervals of 7, 14, and 21 days, respectively. In addition to the main factor, the subfactors included the certified local variety Hashemi, and two varieties, M5, and M12, at three nitrogen fertilizer levels of 60, 80, and 100 kg nitrogen per hectare. The results of this study showed that genotype M5 with 100 kg of nitrogen per hectare and a 21-day irrigation interval had the highest physical water productivity. Under conditions of severe water scarcity during the rice growing season, a 14-day irrigation interval can result in better performance in terms of physical water productivity compared to a 21-day interval, but it leads to lower economic productivity compared to the 7-day irrigation interval. In this study, the certified Hashemi rice variety with the 7-day irrigation interval and 100 kg of nitrogen per hectare showed optimal physical water productivity and the highest economic return under Gilan Province conditions.. According to the results of this study, using alternate irrigation whit a 7-day interval could save 285 million cubic meters of water in the Sefidroud irrigation and drainage network

Urmia Lake, with more than 51,000 Km2 area​​, is one of 6 main Iran’s catchments. Nazluchai, Shaharchai, Bazandozchai, Gadarchi, Mahabadchai and Siminehroud located in west and southwest of Urmia Lake are among the most important rivers supplying the lake. This study aims to evaluate heavy metals health risk including cadmium, lead, nickel, cobalt, arsenic and chromium in surface sediments of western and southwestern rivers of Urmia Lake, for which 22 sediment samples from depth of 0-10 cm was randomly taken and after analyzing by ICP-OES method, non-carcinogenic risk for all studied elements and carcinogenic risk for elements with definite carcinogenicity (cadmium, nickel and chromium) were calculated. According to results, the highest concentrations of nickel, cobalt and chromium were recorded in Baranduzchai and Gadarchai, the highest arsenic concentration was recorded in delta and downstream of Nazluchai and Mahabadchai and the highest cadmium concentration was recorded in Nazluchai delta and downstream of Siminehrood. In mentioned cases, heavy metals concentration is much more than the other parts. Average daily doses of studied heavy metals for children and adults were measured as follows: cadmium <lead <arsenic <cobalt <chromium <nickel. Results also showed that the highest non-carcinogenic risk for children was related to cobalt, chromium and nickel, respectively, while non-carcinogenic risk of cobalt (0.51) and chromium (0.215) is close to the threshold. The overall risk (HI) of all studied heavy metals for children is also close to threshold. Total risk of chromium and cobalt is close to the threshold in 5 and 4 samples, respectively, and in only one sample located in downstream of Baranduzchai, total risk of cobalt has exceeded threshold value. Carcinogenic risk of cadmium and nickel in studied samples does not threaten human health, while carcinogenic risk of chromium is close to threshold and consequently total carcinogenicity risk is close to threshold.

There are different factors involved in water quality and it’s difficult to study all of these factors to assess water quality. Quality indexes are a powerful tool for conclusion and comparison groundwater quality. The current study investigates the integrated water quality index (IWQI) with the Kriging geostatistical technique for the Urmia plain between 2002 and 2011 over a period of ten years. Physicochemical parameters including acidity (pH), electrical conductivity (EC), total dissolved solids (TDS), and ions of calcium, magnesium, sodium, potassium, chloride and sulfate have been used to calculate the index. For different years, 63 groundwater samples were used to calculate the IWQI index and compared with other indexes such as %Na and sodium adsorption ratio (SAR). The results show that most parts of the Urmia plain are in the middle and good class in terms of IWQI classification. Also, the quality in 2004 is better than previous years and the most unsuitable quality is related to 2010. The study of spatial variations of the IWQI indicates the lower quality of the southern parts of the plain than other parts, especially the center part of the plain. As the southern parts of the plain in terms of IWQI classification is often in the middle class, and in 2010 with the decrease in the quality of the entire plain, the southern parts have also decreased to a lower quality class. The center parts of the plain are in a better condition than other parts, especially in 2004, when the quality of the middle class improved to an excellent level. The quality of the northern parts of the plain in terms of IWQI is often in the good class, so that in some years it has changed to the middle class and in 2010 to the poor class.

Because of environmental crises duo to drying of Lake Urmia, the need for applying high efficiency irrigation systems is important in this watershed. Drip irrigation systems are suitable solutions for optimal use of water resources. Drip irrigation implementation requires analysis of water quality to avoid emitters clogging. In this study, qualitative parameters of springs in part of West-Azerbaijan province including the electrical conductivity (EC), total dissolved solids (TDS), sodium adsorption ratio (SAR) and Langelier saturation index  (LSI), were determined and investigated for application in drip irrigation systems in the study area. So, quality information of 1705 springs in the study area were taken from West-Azerbaijan regional water company and analyzed. Results indicated that the LSI has positive values in 87.3% of springs, so there is the Carbonate sedimentation potential. In 11.0% of springs TDS has amounts between 1000-1500 mgL-1 that is hazardous. TDS values in 33.4% have amounts between 500-1000 mgL-1 and in 55.6 % have amounts between 0-500 mgL-1 which are not hazardous. SAR values in 97.7% of springs are in the suitable class. To select a suitable interpolation method to provide the zoning map, various interpolation methods were evaluated using normalized root mean square error (NRMSE) and relative error (RE) statistics and the kriging method with the least errors than other methods, was used to interpolation of quality parameters. Application of spring's water in West-Azerbaijan province for drip irrigation is recommended; however, the risk of emitter clogging especially in the northern parts of the province is high.

Since the most critical periods of life for drug use is in adolescence ,a special attention to the design of prevention programs for this age group appears to be quite critical. To plan and develop effective strategies to prevent substance abuse, in addition to causes and contributing factors in the onset and development of ways to deal with them we must understand the needs and implementing appropriate strategiesto strengthen social abilities and potential step. This study assesses the knowledge, attitudes third year students in Birjand city about drugs.

The study is based on the basic and applied research and the descriptive nature of the survey. Study population included all students (1608 girls and 1641 boys) were enrolled in the academic. to determine the sample size of the table method was used to sample 341 farmers and Morgan were estimated . Random sampling , stratified study. To collect information from both library and field methods were used . The instrument used is a questionnaire with 21 Likert scale items, and the score was . For data analysis, SPSS software and Pearson correlation test , chi-square and t-tests were used .

showed that the students ‘ awareness of their attitudes to drugs , there is a negative correlation (05/0> p). Awareness among students of high and low levels of the drug were found between the amount of interest they knowledge and attitudes among students based on sex and drugs , there was no difference (05/0