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Scarcity of water resources in the entire country is more serious in the northern provinces like Golestan. Therefore, farmers have to use saline water or waste waters. One way to adapt to this condition is to use unconventional water such as Caspian Sea water, with lower salinity as compared with water from free seas, for common crops like soybean. Thus feasibility of using Caspian Sea water that has integrated with narrow common water and the calibration of Aquacrop model under the effect of salinity and water stress for soybean crop in Golestan province are more important. The Aquacrop model assumes a linear relationship between the biomass yield (BY) and crop transpiration one one hand and water productivity (WP) value on the other (Steduto and Albrizio, 2005). This model, as compared to other crop models, requires minimal input data and its new version 4.0 (June, 2012) has a salinity module which was used in this research to simulate the grain yield (GY) and WP of soybean under deficit and saline water irrigation. Furthermore, the AquaCrop model has not often been tested to simulate the yield of soybean under saline conditions in the semi-arid climate of Golestan province. This study aims at evaluating the efficiency of AquaCrop model in soybean yield simulation. The results are to be used for optimizing water consumption under water and saline stress. To this end, an experiment was carried out at the research farm of Gorgan University of Agricultural Sciences and Natural Resources.

The purpose of this study was to model biomass with soil parameters in Hir-Neur rangelands of Ardabil Province. Initially, considering the vegetation types and different classes of environmental factors, at the maximum vegetative growth stage, using one square meter plot, biomass was estimated by clipping and weighing method. For each transect, a soil sample was taken and transferred to the soil laboratory and the various parameters were measured by conventional methods. The relationship between soil factors and the rangeland biomass was analyzed and simulated using linear multiple regression. Among the measured soil factors, the Silt, EC, Ca, Ksoluble, OC, POC, pH, Mg, TNV, clay, P, and volumetric moisture had the highest effect and percentage of biomass forecast (p<0.01). The accuracy of the simulated maps was analyzed using RMSE criteria and for grasses, forbs, shrubs, and total biomass were equal to 0.81, 0.65, 0.34, and 0.46, respectively. The results of this study, not only point out the importance of soil factors on the biomass but also as a baseline data for managing rangelands, supply-demand, and carbon balance can be used in the current section.

Environmental tax and subsidy are two key instruments used in many countries to prevent environmental degradation and to achieve sustainable development. Using game theoretic approach, this paper develops and calibrates a model to determine optimum indirect environmental tax for Iran. More specifically, in the first stage the government sets green taxes and subsides, and in the second stage, the final goods and energy producing firms take these rates and choose their inputs. This dynamic game is solved by backward induction. Prior to our calibration, the production functions for fossil energy, renewable energy - as an intermediate goods - and final goods are estimated. The model is calibrated by using the Iranian data for the period 2015. The results indicate that the optimum green tax rate on fossil energy producing firm and final goods firm are 18 and 9 percent, respectively. These results have important policy implications for policymakers and social planners in Iran.

Introduction: Iran is rich in renewable and unrenewable energy resources. Iranchr('39')s geographical position makes it a great source of energiessuch as solar and wind power energy. Increasing of need to the energy, limitation of fuel burn resources, increasing of the environment pollution due to fuel burns consumption, global warming, acid rainfall defluxion, necessity of equipoise of carbon dioxide diffusion and reduction of fuel burn consumption have been increased pay attention to renewable energy resources. Among renewable energies, wind power is one the best resource to acquire electrical energy. This energy doesnchr('39')t infect the environment.The conventional energy resources such as oil, natural gas, coal, or nuclear are finite and generate pollution. In contrast, the renewable energy sources like wind, solar, biomass and geothermal are clean and frequently available in nature.The wind as one of the bestfacile of renewable energies is very important for use instead of fossil fuels. Due to the uncertainty of the prediction of the energy production, it is important to have additional information about prone area to produce the electrical energy. Iran as a developing country needs to new sources of clean energy. Wind energy is very useful because of its low environmental impact and high sustainability. The mainly aim of this research is an assessment of wind power situation and an evaluation of wind energy potentialin Chaharmahal and Bakhtiari province in Iran. Data and Method: The area under study of this research is Chaharmahal and Bakhtiari province that is located at southern west of the country. This region covers 1% of total country area. Due to geographical and topographical characteristics, the climate condition is variable and there is different climate in this region. The annual precipitation is affected by Mediterranean systems and Soudan low pressure. Wind data used in this study were obtained at 10 meters above ground level from Iranian Meteorological Organization at three-hour intervals in 27 years statistical period.Wind speed and direction were averaged over tree-hour periods. Then, Data were arranged annually in Excel software. Wind measurements are available from 1988 to 2014. The wind speed was recorded in knots. Consequently, the data units were converted to m.s-1. Weibull probability distribution function was used to calculate the probability of the data. The frequencies of each wind velocity category were extracted at different times. For calculating the Weibull parameters, Ordinary Least Squares method was used. First Chi-square testwas performed for all stations of the study area. Then, the stationsthatdid not follow from Weibulldistribution were excluded. For calculating the Weibull parameters, Ordinary Least Squares method was used. Using the one-seventh law, wind data in 10 meters converted to 50 meters. Results and Discussion: The wind power potential in 10 meters height was obtained in Borujen, shaherkord andKoohrang200.12, 167.41,154.68 W.m-2,respectively. Results showed that wind power potential is increasing with heightinallstations. The resultssuggestthat, the potential forwind energyproduction in Borujen is more than Koohrang and Shahrekord stations.The highest wind power density at all three stations was obtained in winter.In annual scale, wind existence hours in Shahrekord, Borujen and Koohrang were obtained 3404.4, 3476.1 and 2775.6, respectively.Consequently, the highest wind existence hour in annual scale is related to Borujen station and the lowest wind existence hour is belonged to Koohrang station. The most important consequence of the study can be summarized as follows: 1) among the three selected station,Borujen is most suitable for electric wind production. 2) The Weibull distribution presented here showed a good fitness with the observed data. 3) Winter season have the highest wind power density. 4) January and March months are the two months that the average wind speeds are the highest over the year. Conclusion The obtained results of this research showed that between the selected stations, the highest Rated Wind velocity in annual scale is related to Borujen station. In this station, Rated Wind velocity in 10 and 50 meters reaches to 9.83 and 12.32 m.s-1, respectively.The lowestRated Wind velocity belonged to Koohrang station by 9.35 m.s-1 in 10m height. For this reason, Borujen city is an appropriate site to product of wind energy. Results also showed that the highest Probabilistic Wind velocity is related to Borujen station with values of 4.51 and 5.64 m.s-1 in the heights 10 and 50 m, respectively. It is important to note that wind velocity probability in the height between 2 to 150 m in Borujen and Shahrekord is more than Koohrang station. The highest wind density in 10 m height belonged to Borujen station. Results also showed that in three selected stations, the highest wind power density was obtained in winter season. In the monthly scale and in Shahrekord and Borujen stations, the highest wind power density were observed in March while in Koohrang was seen in January.

Global warming caused by excessive consumption of fossil fuels and carbondioxide emissions is becoming the most important environmental issue in theworld. Tourism industry causes 5% of total carbon dioxide and 14% of totalgreen house of the world. Energy consumption in tourism is in direct relationwith tourists behaviors. To succeed in changing unsustainable behavior andreinforce sustainable behavior should be aware of the factors affecting it. Thisstudy explores the factors affecting the tourists’ intentions to conduct lowcarbonbehaviors from a Protection Motivation theory perspective. Populationof the study consists of Tehran citizens of district 1, which are selected by multiStage Cluster Sampling. A questionnaire was used to collecte data. Foranalyzing collected data, structural equation modeling was used. Findings showthat variables of tourists “Perceived vulnerability”, “Perceived responseefficacy” and “Perceives self-efficacy” have the most effect on their low carbonbehavioral intention respectively

Abstract Objective & Background: The aims of this study were to investigate the effects of planting methods on riased bed with microirrigation and seed density on grain yeild and energy indicators of bean production. Materials & Methods: In order to compare the effect of planting methods and seed density on bean line of COS-16 (Straight Type), a split plot experiment in randomized complete block design was carried out in Khomein Bean Research Station during 2016 and 2017 with 3 replications. The main plots were flat planting, single row on a ridge, double rows on a ridge and three rows on a ridges. Sub plots were seed consumption of 70, 120 and 170 kg.ha-1. The space between ridges was 75 Cm. Irrigation type was microirrigation (tape irrigation). Results: Experiment results showed that the treatments of two rows on a ridge with seed consumption of 120 kg.ha-1 and single row on a ridge with seed consumption of 70 kg.ha-1 with yields of 2300 and 2225 kg.ha-1, respectively are beter than other methods. The lowest energy intensity with 34 MJ.kg-1 and the high energy ratio with 0.99 were related to these treatments. Energy intensity and energy ratio of conventional method were 53.7 MJ.kg-1 and 0.63 respectively. Conclusion: The treatments of two rows on a ridge with seed consumption of 120 kg.ha-1 and single row on a ridge with seed consumption of 70 kg.ha-1 are recommended and the flat and three rows on a ridge planting methods does not recommended.

In the early 1980s, an alien ctenophore Mnemiopsis leidyi already known as a gelatinous zooplankton was transported (likely via ballast waters) to the Caspian Sea from its introduced or native water of the Black Sea or western Atlantic which caused negative impacts. In this report, distribution of M. Leidyi, planktonic and benthic organisms had been investigated in the Southern Caspian Sea (Iranian waters) in 6 transects consisted of Lisar, Anzali, Sefidroud, Nowshar, Babolsar and Amirabad at 26 stations during 2005 and 2006. As a whole, 1422 samples had been analyzed included 258, 346, 217, 117 and 484 belong to ctenophore, phytoplankton, zooplankton, benthos and physicochemical parameters, respectively. M. leidyi abundance and biomass were fluctuated between 284-2751 ind.m-2 and 16.9- 390/9 g.m-2 respectively in 2005 while maximum abundance and biomass were recorded in autumn and minimum in winter. In 2006, its mean abundance and biomass were 184-2150 ind.m-2 and 9.1- 209/8 g.m-2 respectively. M. leidyi maximum abundance and biomass were noted in summer and its minimum in spring and winter months. Overall, mean M. leidyi abundance and biomass were recorded in 20 m within 1202 ind.m-2 and 139.5 g.m-2 respectively. Maximum size of the ctenophore was recorded as 55 and 60 mm in 2005 to 2006 respectively, while less than 10 mm length frequency consisted 83.16 and 82.88 per cent of total population. Spatial_ temporal distribution of M. leidyi in different regions showed it was more abundant in west and east (714- 4494 ind.m-2) ratio to central parts (13-1519 ind.m-2) of the Southern Caspian Sea. Species composition of zooplankton had shown the negatively impacts of M. leidyi invasion in the period of sampling as the only 17 holozooplankton were determined with Rotatoria (7 species), Copepoda (4 species), Ciliophora (4 species) and cladocera (1 species). Zooplankton maximum abundance and biomass were recorded in February (3039742901 ind.m-3 and 372.1575.4 mg.m-3) respectively and its minimum were in July (12211601 ind.m-3 and 6.9 7.7 mg.m-3) respectively which was belonged to Rotatoria (76%) and Copepoda (10%). In this study, 21 species of benthic fauna were deter minted belong to Pseudocumidae (5 species), Gamaridae (4 species) Amphartidae (3 species), Oligochaeta, Balanidae, Xantidae, Nereidae, Scarbicularidae, Carididae, Mytilidae, Herpobdellidae and Chironomidae (each 1 species). Oligocheata was recorded with maximum abundance (943 2502 ind.m-2) and Bivalve consisted of higher biomass (68.7162.5 g.m-2). From five phyla of phytoplankton, 172 species were determined of Chrysophyta (74 species), Cyanophyta (32 species), Chlorophyta (32 species), Pyrrophyta (24 species) and Euglenophyta (13 species), in which Chrysophyta and Pyrrophyta were noted as main groups with their maximum abundance (up to 65%) and biomass (93%). Maximum water temperature was recorded in August with 29.52.5 ֯C and minimum in February by 9.31.3 ֯C. Mean value of salinity was 12.010.90 ppt, secchi disk ranged between 0.2 to 7 m and oxygen demand varied from 5.95 to 10.54 mg. l-1). Moreover, silicate concentration was recorded between 200 to 300μg.L-1, Phosphate measured from 31-47 μg.L-1, Ammonia varied in 10-29 μg.L-1, Nitrite (0.6- 1.7 μg.L-1), Nitrate (0.06-4.20 μg.L-1, which mainly accumulated in coastal waters of the southern Caspian Sea. Iranian Fisheries Science Research Institute Published

With the global warming and introduction of serious issues and concerns realting to the escalation of greenhouse gases, which directly affects the lives of flora and fauna, and the role of polluting gases such as carbon dioxide, man has strived to deal with this problem using new technologies. One of those technologies is to capture and store carbon dioxide under the seabed. Nevertheless, legal rules governing the different aspects of this process are not clear. Although, 1982 LOSC rules, 1975 London Convention and its additional protocol (2006) and even some European Union directives that contain provisions in this area are significant, but still some existing challenges, including the environmental consequences resulting from the use of this technology requires serious attention in the international practice and relevant legal documents. In this paper we will briefly examine the existing legal capacities and some of the challenges relating to this technology.

Detecting trend and stationarity in hydrological time series may help us to understand the possible links between hydrological processes and global climate changes. The main purpose of this study is to find any possible relations between streamflow and temperature trend and climate changes. Trend analysis with Mann-Kendall and seasonal Kendall test showed that there is no trend in annual mean discharges but monthly flow series exhibit significant downward trend in specific months. Stationarity tested with five methods which are ADF test, Dickey-Fuller test with GLS detrending (DFGLS), KPSS test, Phillips and Perron test and Elliot, Rothenberg and Stock test. Most annual and monthly discharge series appear to be significantly stationary. All methods for 10 days and daily flow series cannot pass stationarity test even at 1% level. Nonstationarity on daily and 10days timescale might be the result of climate changes. The results imply that because of high dependence of rivers located in the west of UrmiaLake on snow melt water, and temperature, climate change is the main cause of downward trend of ShaharchiRiver and Urmia lake depletion.

The aim of this study was to investigate the effect of seed maturation on germination, growth and seedling quality index of common ash (Fraxinus excelsior L.) in Kelardasht forest nursery. In 2017, the seeds of immature in late August and the seeds of mature in late November were collected and following stratification in moist sand were sown in nursery bed in mid-Feberaury each with three 100-replications . From the mature seeds, some of them germinated in 2nd year (April 2018) and the seed germination, biomass and quality indices of their seedlings were statistically (paired t-test) compared with the results of immature seeds germinated in spring 2017. The highest percentage of cumulative germination allocated to the immature seeds, followed by mature seeds germinated in 2nd year. Due to the lack of germination of most of the mature seeds in spring 2017, showed the seed dormancy, their germination traits were not considered in the statistical test. Germination percentage, mean germination time and germination speed and also, dry biomass, root biomass, root length and seedling quality index in immature seeds were greater than those in mature seeds germinated in second year. Generally, it is best to collect the seedlings of immature seed in order to achieve the optimum germination and growth, because the mature seeds are often dormant and unable to germinate during the first growing season. If mature seeds are supplied, it is advisable that these seeds to be stratified until spring of the second year.