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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.

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.

Introduction: Minerals are one of the main components of soils which play different roles in the soils. Minerals make up about 50% of the volume of most soils. They provide physical support for plants, and create the water- and air-filled pores that make plant growth possible. Mineral weathering releases plant nutrients which are retained by other minerals through adsorption, cation exchange, and precipitation. Minerals are indicators of the amount of weathering that has taken place, and the presence or absence of particular minerals gives clues to how soils have been formed. The physical and chemical characteristics of soil minerals are important consideration in planning, constructing, and maintaining of buildings, roads, and airports. Clay minerals can be used for understanding of soil formation, optimum management of dry and wet lands and interpretation of paleo environments. Moreover, clay minerals can provide some valuable information such as the origin of sediments, transportation and precipitation of sediments and also some information about intercontinental weathering regimes. Quaternary sediments have occupied most of the agricultural and natural resources of Urima plain and recognition of mineralogical of these soils is essential to optimum and stabile use of these soils. Additionally, caly mineralogical investigation can provide some information about the intensity of weathering processes and climate change in this area. Thus, in this study clay minerals of quaternary sediments in northeast of Urmia and the mechanisms of their formation and also tracing probable climate change in this area were investigated. Materials and Methods: This study was performed in theUrmia plain in west Azerbaijan Province. The study area is located on quaternary sediments and physiographically, this area is a part of a river alluvial plain with the gentle slope toward Urmia Lake. The mean annual precipitation and temperature of this area are 345.37 mm and 10.83 °C respectively and the soil moisture and temperature regimes are dry xeric and mesic respectively. In this study, eight soil profiles in quaternary sediments were dug and sampled and the morphological, physical, chemical and mineralogical properties were determined using standard methods. Results and Discussion: According to the results, Illite, smectite, Kaolinite, chlorite, vermiculite and hydroxy interlayer vermiculite (HIV) were the dominant clay minerals in these soils. The origin of illite, chlorite and kaolinite were related to inheritance from parent material. Regarding to the present of some smectite in the parent material of these soils, some of smectites have been inherited from parent material. Nevertheless it seems that, the most of smectites in these soils have pedogenic origin. Based on mineralogical results and trends variation of smectite and illite along studied profiles, we concluded that some of smectites in these soils have been formed from illite transformation. In profiles 4 and 6, regarding to low depth water table and consequently poor drainage, high pH and high values of calcium and magnesium cations, provide suitable conditions for the neoformation of smectit and so, some of smectites have been formed via neoformation from soil solution. In these soils, vermiculites were pedogenic and have been formed during transformation of illite to smectite. Small amounts of hydroxy interlayer vermiculites were present in buried horizons and regarding that they were not present in parent material, it might be because these minerals are pedogenic and have been formed in a past wetter climate. The transformation of illite to smectite in lower horizons needs high moisture and regarding to recent semiarid climate of study area, the suitable amount of moisture for this transformation, especially in lower depths and also in buried horizons, is not present. Thus, it seems the transformation of illite to smectite in lower depths and buried horizons has been taken place in a wetter past climate. So we concluded that smectite and hydroxy interlayer vermiculite are evidences of a wetter past climate in this area. Conclusion: In this study the origin of smectite in buried horizons was related to transformation of illite. According to high moisture condition which is necessary for the weathering of illite, the occurrence of this process related to more humid climate of the past. Additionally, the presence of hydroxy interlayer vermiculites was related to previously wetter climate as well. So results of this study can be used for recognition of climatic change in the study area.

Background and Objective: Study was conducted to evaluate the sustainability of the two autumn and spring potato (Solanum tuberosum L.) farming ecosystems. Methods and Materials: The study was conducted by questionnaire in Golestan Province during the period of 2017-2018. 120 autumn farms and 60 spring farms were selected by stratified random sampling method. After determining inputs and output and their energy equivalent, the energy indices were determined. Results: Fossil fuels and fertilizers were the largest energy inputs of the total in autumn and spring potato farming ecosystems with share of 30.26% and 29.04%, respectively. In autumn and spring potato farming ecosystems, energy use efficiency indices were 1.85 and 1.30; energy productivity indices were 0.51 and 0.36 kg MJ-1; specific energy indices were 1.95 and 2.76 MJ kg-1; net energy indices were 52135.16 and 16125.42 MJ ha-1; mechanization indices were 0.96 and 0.94; total energy inputs were 61384.83 and 53234.59 MJ ha-1 and total energy outputs were 113519.99 and 69360.01 MJ ha-1, respectively. Conclusion: The efficiency and the sustainability of the autumn farming ecosystem were higher than the spring in terms of potato production in Golestan Province. In autumn and spring farming ecosystems, the share of indirect, nonrenewable and commercial energy were greater than that of direct, renewable and noncommercial energy. It is useful to implement recommended guidelines for optimal management of inputs such as conservation tillage, modernization of machinery and consumption of manure, it reduces the share of nonrenewable and commercial energy and increases environmental health and energy efficiency.

Climate change has serious impacts on communities and livelihoods in dry areas. The agricultural sector accepts the greatest impact from climate change due to its extensive interactions with the environment. Environmental degradation and reduced yield of saffron and weakening of the household economy are among the consequences of climate change in the Kashmar plain. This study was carried out in order to evaluate the perception of saffron in the Kashmar plain from climate change and its capacity to adapt to this phenomenon. The present study was conducted to examine the perceptions and adaptation of saffron to climate change in order to expand the strategies for confronting the climate change challenges in the Kashmar plain. The method of this study is descriptive-analytic. The population of the study was calculated using Cochran's sampling method and a sample size of 390 households was chosen. Statistical models such as logistic regression were used to examine saffron perception and compatibility strategies. The analysis of saffron perceptions of climate change shows that the increase in temperature and the decrease in rainfall during the last decade in the Kashmar plain has been ongoing. The results of the logistic statistical model indicated that product diversity, change in crops, finding a job outside the farm, changing the amount of land, changing the planting date of saffron were adaptation methods used in the region. Given that many saffron growers have come to understand climate change and adjust their farming activities based on these changes, the government should facilitate the adaptation of saffron to climate change.

Controling weeds at their critical periods of growth leads to low production costs and injurious effects of using chemical weed controling methods. In this experiment we studied the timinig effects of weed control (interference of weeds after 20, 40 and 60 days and complete control of weeds) and weed interference periods for 20, 40 and 60 days after planting and complete interference) on growth and yield of forage maize CV. 454. The experiment was conducted incomplete randomized blocks design with three replications at the Research Farm of Islamic Azad University of Tabriz Branch in 2013. According to the results, maintenaning the farm for 40 and 60 days under weed interference after 20 days prevented reduction of maize biomass, while weeds interference after 20 days, weed interference and controling weeds after 40 and 60 days resulted in 41.2%, 35%, 25% and 32.5% reduction of forage maize biomass, respectively. Reduction in fresh weight of corn and fresh weight of leaf and stem were also observed due to interference of weeds after 20 days. If weeds are controlled after 60 days, reduction of corn weight and fresh weight of stem will also results in reduction of biomass. Also, if weeds are controlled after 40 days, stem fresh weight of maize will result in biomass reduction. Corn traits were affected by weeds control treatments. Being affected by treatments of weeds interference after 20 days, weeds non-interference, controlling weeds after 40 and 60 days, the height of corn was reduced by 29.9%, 41.4%, 27.6% and 37.2%, respectively. The stem diameter demonstrated a significant reduction, although it was only affected by treatments of weeds interference and weeds control after 60 days. Based on the results of this study, it may be suggested that controling weeds during initial 20-60 days of maize growth would prevent the undesirable effect of weeds on growth, production and biomass production of maize and also results in production costs.

Current conventional agricultural systems using intensive energy have to be revitalized through new integrated approaches relying on renewable energy resources, which can allow farmers to stop dependence on fossil resources. The aim of this study was determining the amount of input–output energy used in onion (Allium cepa L.) production in Khorasan Razavi province. For this purpose, the data was collected from 55 onion farm workers in Khorasan Razavi. Inquiries were conducted in face-to-face interviews in April-May 2011. Farm workers were selected based on random sampling method. The results indicated that total energy input was 98479 MJ.ha-1. The share of electricity and nitrogen fertilizer was 50.9 and 14.7%, respectively out of total energy input. The average onion yield under normal conditions was 73227 kg.ha-1 on irrigated farms. The net energy and energy productivity values were estimated to be 18684 MJ.ha-1 and 0.74 kg.MJ-1, respectively, and the ratio of energy output to energy input was found to be 1.19. This indicated an intensive use of input in onion production, which is not parallel to the increase in the final yield. Approximately 77.3% of the total energy input used in onion production was non-renewable (machinery, diesel, fertilizers, chemicals and electricity) and only 22.7% was renewable energy form (human labor, manure, water for irrigation, seeds). Cost analysis revealed that total cost of onion production for one hectare was 79262908 Rials. Benefit–cost ratio was calculated as 1.65. Although energy efficiency of onion production in Khorasan Razavi province is low, it is economically justified.

Introduction: Garlic (Allium sativum L.) is an important winter crop in northern of Iran with a total of 9580 ha which produces approximately 90, 197 tons per year. It is the second most widely cultivated species of the genus, Allium after onion (Allium cepa). Also, Garlic along with onions and leeks are three major cultivated species in Alliaceae family. This plant because of high economic and medicinal values is cultivated in 2610 hectares of agricultural lands of Mazandaran Province, Iran. Slow growth rate, low height, and a thin canopy that does not cover the soil enough to sup-press weeds make garlic a poor competitor against the latter until the beginning of spring. According results, reported 71% yield losses in garlic crop if weeds are allowed to grow during the crop season. Weed interference is affected by the time of weed emergence relative to the crop’s phenological development. The weeds, which emerge early or simultaneously with the crop, are highly competitive and should be managed by farmers. Most weed management strategies in cereals target seedlings, as they are the most sensitive stage of the weed. However, emergence of weed seedlings varies every year in timing, extent and intensity. Therefore in this study, the effect of chemical management on reducing the density and biomass of weeds, yield and agronomic characteristics of garlic were studied in Mazandaran Province, Iran. Materials and Methods: After the selection of location test, in order to determine the physical and chemical properties before the preparation of soil for planting, sampling from the soil was carried out from the depth of 0 to 30 cm at some point. The farm was plowed using a moldboard plow, then the used fertilizers in this study were added to the soil twice before planting and then the fertilizers were incorporated with the soil using a Disc. The amount of used fertilizers in this study according to soil test were including: 200 kg Urea per hectare that 100 kg as the base and 50 kg in two foliage stage and 50 kg in 4 foliage stage of garlic, 200 kg superphosphate triple per hectare, and 100 kg potassium sulfate. The research was performed in a land with area of 300 m2 containing 30 plots with dimensions of 3×3 m2. The planting process was done after disinfection of garlic seed varieties of Mazand for 24 hours in a solution of 2% carboxin thiram with the distance of 30×15 cm and the density of 23 plants per m2on 23/10/2012. After about two weeks from planting of garlic, germination was fully performed. The studied factors in 10 dosages of herbicide are including: 1.5, 2 and 2.5 liters per hectare of Trifluralin (Terflan) via formulations (EC 48%), 1.5, 2 and 2.5 liters per hectare of Oxyfluorfen, 1.5 liters per hectare of Oxyfluorfen in two stages (the half in first stage and the rest 18 days later) via formulations (EC 24%), hand weeding control and lack of weeding control (the number of replications of these two treatments were two folds of others (2 replications in each block and 6 replications in total)). Two weeks before planting Trifluralin herbicides were incorporated with the soil and Oxyfluorfen herbicides as post-emergently were applied in the 3 to 4 foliage stages of weeds using a backpack sprayer pump from the side of the nozzle sag (T-Jet). After 145 days from planting, 10 plants per plot were selected and plant heights measured. After maturity of garlics, 10 plants of garlic were eradicated and the number of cloves per bulb was counted and weight of 100 cloves of garlic was weighed. After full maturity of garlic, a square meter of each plot was harvested on 7.5.2013 and the harvested plants was placed for 48 hours in the farm and then bulb yield and biological yield were weighed and harvest index was also calculated. Statistical analysis software SAS (version 9.1) was used for analysis and the obtained averages were compared by means of the Duncan least significant difference test. Results and Discussion: Results showed that the use of different doses of various herbicides had a significant difference on the plant height, weight of 100 cloves, economical and biological yield and harvest index of garlic. In contrast, under treatments of the usage of 1.5 liter of Oxyfluorfen in two stages and hand weeding treatment, plant height of garlic was increased due to lack of competition with weed species and no significant difference was observed between the above treatments with the usage of 1.5, 2 and 2.5 liters of Oxyfluorfen. The adverse effect and phytotoxicity of garlic under the use of different doses of 2 and 2.5 liters of Oxyfluorfen caused disturbances in the production of cloves per bulb of garlic and the plant spent their photosynthetic products in the reclamation of its shoots. In contrast, the highest number of cloves per bulb were counted under the treatments of using 1.5 liter of Oxyfluorfen, hand weeding and 1.5 liter of Oxyfluorfen in two stages. The results showed that the highest economical yield of garlic was obtained in the treatment of using 1.5 liter of Oxyfluorfen, hand weeding treatment and splitting of 1.5 liter of Oxyfluorfen in two stages, and there were no significant differences between the above treatments. The plant used the best from the resulted ecological niche in normal conditions, and it could transfer more photosynthetic materials to the reproductive organs and it could increase the bulb yield with more producing of cloves per bulb with higher weight. Conclusion: The results obtained from experimental trials on plant height, cloves number in the bulb, cloves weight and ultimately economic yield of garlic (bulb) showed that the treatment of using 1.5 liters of Oxyfluorfen in 3 to 4 foliage stages of weed species was the best treatment.

Life cycle assessment (LCA) is a well-known and accurate methodology for comparison of environmental impacts of activities including different agricultural management systems. Since the used inputs have an important role in environmental pollution and greenhouse gas emissions, LCA have been extensively applied for crop species. This study was conducted to assess the environmental impact of saffron production systems based on field area (1 ha) in the Khorasan-e Razavi province using LCA methodology. The amounts of utilized agricultural inputs from the first year to the sixth year were collected by means of a questionnaire (13 fields from each area). In this regard, four phases, which are goal and scope definition, inventory analysis, impact assessment and interpretation, were designed to assess life cycle index with ISO14044 procedure. Functional unit were considered as one kg of flower. Three main categories as impacts on environment including global warming, acidification and eutrophication (terrestrial and aquatic) were defined. Finally, an index -called environmental index (EcoX) was calculated. Cronbach's alpha was used assessing the reliability of the questionnaire. The results showed that the Cronbach's alpha was computed with α=%84. The average values for global warming, acidification and eutrophication terrestrial and aquatic categories were calculated with115.41±53.41 kg CO2 equiv. / one kg flower yield, 0.35±0.16 kg SO2 equiv./ one kg flower yield, 0.58±0.27 kg NOx equiv./ one kg flower yield and 0.20±0.09 kg PO4 equiv./ one kg flower yield, respectively. The largest share of greenhouse gas emissions in the global warming category was related to CH4. The maximum emission of pollutants in acidification, eutrophication terrestrial and eutrophication aquatic categories was related to NH3. The results revealed that, field area affected the amounts of utilized agricultural inputs and environmental impacts as flower yield. Eutrophication and climate change categories had more sensitivity and affected as intensification based on field area. Therefore, one of the appropriate approaches to mitigate and decline the environmental impacts of agricultural production is achieving higher economical yield per unit of area by increasing resource use efficiency.

In forest ecosystems, forest production, storage and carbon flow are calculated based on biomass measurements. The aim of this study was to compare the biomass and carbon stock of the above-ground, litter and soil in the oak decline and control plots in Chaharmahal and Bakhtiari province. Four one-hectare sample plots were selected in the healthy (control) and declined stands of oak. Then quantitative information of all trees were measured. Allometric equations were used to calculate the above-ground biomass and carbon stock. Ten microplots were established in each sample plot and all litters were collected. Wet and dry weights and carbon content of the litter samples were measured. To measure soil organic carbon, five soil samples were taken in each sample plot. The results showed that above-ground biomass in the control and decline sample plots were 31.4 and 15.8 tons/hectare respectively. Also, the average of the above-ground carbon stock in the control and decline plots were 15.1 and 7.7 tons/hectare, respectively. The mean of litter carbon in the control plots was 1584.1 kg/ha and in the decline plots was 1148.6 kg/ha. The amount of carbon, nitrogen, phosphorus and soil moisture content showed a significant difference between the control and decline plots. The results of this study indicated significant changes in biomass, carbon stock and soil in declined stands of oak which may cause irreparable damage to the Zagros forest ecosystem, in the long term. This issue highlights the need for the attention of managers and decision makers of natural resources, regarding the provision of management solutions to control this phenomenon.