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Abstract Background and Aim: Increasing energy consumption has created an energy crisis in the world. Fossil fuels are limited and depleting. Biogas is considered a fuel that has attracted the attention of researchers. To increase biogas production, different pretreatments have been utilized. The purpose of this study was to investigate the optimal mixing ratio of Municipal Solid Waste (MSW) and Sewage Sludge (SS), as well as the effects of various conditions of alkaline pretreatment on biodegradability of wastes and the amount of biomethane production. Materials and Methods: This study was done in a laboratory digester with 1 L volume at 37 °C with different concentrations of NaOH in a completely randomized design. Biogas volume, methane volume, and changes in pH were measured daily. Measurement parameters in the anaerobic digestion including total solids, volatile solids, and carbon and nitrogen content in the feedstock were determined according to the APHA standard methods. Results: The optimal mixing ratio of MSW to SS was 60:40 with the highest methane yield of 254.87 mL/g VS. Next, the effects of 2, 6, and 10% NaOH concentrations were evaluated on the amount of gas produced, indicating that 6% NaOH concentration significantly improved waste decomposition. Methane production, VS, and TS removal were compared to the control treatment, and there were increases of 30, 27.94, and 27.25%, respectively. Conclusion:The results showed that the mixing ratio of MSW to SS at 60:40 with 6% NaOH improves the decomposition of organic wastes and increases biomethane production. Keywords: Alkaline Pretreatment; Anaerobic Digestion; Biogas; Municipal Solid Waste; Sewage Sludge

In this study, the effect of some soil parameters on the life forms and total aboveground net primary production (ANPP) in meadow rangelands in Fandoghlou region of Namin county in Ardabil Province were investigated. ANPP in 180 plots of 12 by harvesting and weighting method were measured. Eighteen soil samples were collected along transects. Some physical and chemical attributes of the soil were measured by standard methods. The relationship between these parameters and ANPP was performed using multivariate regression (enter) method. To determine the effects of important soil parameters on ANPP variation, principal component analysis (PCA) was used. The results of regression analysis showed that electrical conductivity (EC), magnesium (Mg), spreadable clay (WDC), volumetric moisture content (VM), organic carbon (OC), soluble potassium (KS), exchangeable potassium (Kexch), sodium (Na) and phosphorus (P) were the effective parameters on the life forms and total ANPP (p<0.01). The accuracy of obtained equations for grasses, forbs and total ANPP were calculated 79, 76 and 70%, respectively. Moreover, results of PCA showed that soil parameters justify 84.52 percent of total ANPP variation and in comparison, with regression results with 28% it provides better results.

Background and Objective: In recent years, management and disposal of municipal solid waste has become a global problem and the most important environmental concern. Anaerobic digestion is a cost-effective solution for treatment of both solid waste and wastewater. The aim of this study was to investigate the positive or negative effects of calcium chloride content in anaerobic digestion process of municipal solid waste and leachate on biogas production. Materials and Methods: Experiments with 8 levels of calcium chloride on co-digestion of municipal solid waste and leachate were investigated in 500 ml digesters under mesophilic conditions in a completely randomized design with three replications. Reactors with a ratio of substrate to inoculum of 2 (on VS basis) were operated and the volume of the biogas was measured daily. Volatile and total solids, carbon/nitrogen of waste, COD, BOD and heavy metals were measured by following APHA. Results: The results of the experiment showed that the pH was decreased with increasing calcium chloride concentration. The highest amount of cumulative biogas production was obtained in CaCl2 of 2 g/L with the highest VS and TS reduction. Higher concentrations of CaCl2 (≥3 g/L) caused a reduction in the degradability of volatile and total solids and, as a result, a decreased performance of the digester. Conclusion: The results clearly confirmed that the addition of calcium chloride was an effective solution to improve biodegradability in co-digestion of the MSW and leachate and consequently to reduce the total and volatile solids and to increase the amount of‌ biogas.

Today’s world faces two major crises including environmental pollution due to fossil fuels and the reduction of these fuels, so energy supply through renewable energies has been considered a sustainable solution. The purpose of this study was to assess factors affecting the tendency to use biofuels among villagers. Heads of households in rural areas in Chavarzagh district, Tarom township, Zanjan province formed the statistical population of the study (N=2742). The sample size was estimated using the Cochrane formula (n=161) and samples were selected using multi-stage cluster sampling method. The descriptive and correlational research method was used in this study. The validity of the questionnaire was approved by a panel of related faculty members. Cronbach's alpha coefficient was used to confirm the reliability of the questionnaire (0.70-0.83). Data was analyzed using SPSS 21. Regression analysis showed that risk, attitudes towards biofuels, self-efficacy, training, eliminating subsidies for fossil fuels and encouraging the use of biofuels, increasing public awareness about the benefits of biofuels and perceived barriers explained 40.6 percent of the variation of villagers’ tendency to use biofuels.

The higher levels of essential elements in soil may be caused in optimum yields and crop quality. So it seems to be necessary to examine different levels of nutrients like Fe and Zn on plants and their productivity. To evaluate effects of iron and zinc application on yield and yield components of Pimpinella anisum an experiment was conducted at the research farm of Urmia University in 2009. Treatments, iron application (0, 0.2, 0.4 and 0.6%) and zinc (0, 0.2, 0.4 and 0.6%), were arranged as factorial based on randomized complete block design with 3 replications. Results showed the significant effect of interaction between iron and zinc on the number of seed in per plant,1000 seed weight, biomass yield, seed yield and harvest index (HI). The maximum value of the 1000 seed weight (2.22 g) was obtained from 0% of Fe and 0.2% of Zn, whereas the minimum value of the 1000 seed weight (1.92 g) belonged to 2% of iron and 0% of zinc. The highest number of seed per plant (762), maximum value of biomass yield (2652 kg/ha) and highest of seed yield (1372 kg/ha) were obtained from 0.6 and 0.4 percent of Fe and Zn and the lowest number of seed per plant (272), maximum value of biomass yield (716 kg/ha) and highest of seed yield (470 kg/ha) were obtained from 0 and 0.6 percent of Fe and Zn, respectively. The highest HI (66.18) was obtained at control treatment and the lowest one (46.67) at both 0.4 percent of Fe and Zn. The essential oil percent increase in average values of Fe and Zn spraying. But accumulation of Fe and Zn were the maximum in higher levels of spraying.

Abstract Background & Objective: Agriculture is one of the most important activities, whereas observing ethical dimensions (human, environment, animals, society, economy and policy) are necessary. Therefore the purpose of this study was develop strategies to apply ethics in agricultural in Sonqor County. Materials &Methods: This study is a Qual-Quan research. The study population consisted of experts and farmers producing healthy products in the city of Sonqor (n = 32) who were selected purposefully. Results: Based on results, comprehensive government attention to Agricultural ethic and financial, technical, and legal support from the farm food to the table ( ) as a first strategy and evelopment of good agricultural production for all products, regional, national, international contracts and agreements in order to meet the needs of healthy consumer markets ( ) as a second important strategy was recognized which both of them are among the aggressive strategies. Also result showed that considering ethical actions towards development of sustainable agricultural, allocation of annual budgets, leading agricultural education to ethical agriculture (WO) are the most important conservative startegies. Conclusion: in the current situation in study the, aggressive strategies should be prioritized. This means that with considering the factors affecting the non-observance of ethics in agriculture, instutational development in this area, amend the rules, guidelines and most important social institutions and ethicl norms in the community of farmers need to be addressed in this county. In this regard the approach of farmers and related organizations should be changed toward appliying manifest of ethic in agriculture.

Background and Objective: In this study, effects of residue management, irrigation methods, tillage systems and planting methods on some important aspects of common wheat-maize rotation in Khuzestan province was investigated. Materials and Methods: The experiment was conducted as strip-block split factorial on randomized complete blocks design with three replications. Residue management considered as main plots, irrigation methods as subplots and factorial combination of tillage systems and planting methods as sub subplots. Results: Retaining residue on surface in flood and drip tape irrigation systems increased maize harvested about 0.4 and 0.18 kg per each m3 of applied water, respectively. In conservation tillage practices, reduced tillage and no-tillage with residue on surface had no significant effects on wheat and maize yields compared to conventional tillage, but improved water use efficiency, energy productivity and economic indices. The highest benefit to cost ratio (BCR) was obtained as 1.72 from drip tape irrigation-with total residue-conventional tillage- ridge bed planting treatment. The lowest input energy (76635 MJ.ha-1) and the highest energy productivity (0.210 kg.MJ-1) was belonged to drip tape irrigation-with total residue-no tillage- ridge bed planting treatment, Also BCR in this conservation system was obtained 1.62. Conclusion: Moving towards adoption of agricultural conservation techniques such as retain residue, reduce tillage, planting on permanent ridge bed and use high efficiency irrigation methods would result in a sustainable production. According to the results of this research, the use of conservation tillage systems are recommended.

One of the main sources of greenhouse gas (GHG) emissions is the use of energy for groundwater pumping. Reducing energy consumption is very important to achieve the environmental sustainability and decrease the climate change impacts. In this paper, the amount of greenhouse gas emissions from groundwater pumping in the Guilan’s aquifers was investigated. Firstly, groundwater depletion and the types of pumps for water pumping were examined in the current condition; then, the values of consumed energy, GHG emissions and climate change indicator of the current condition were estimated. The primary investigations showed that 55 percent of wells in the studied region had a diesel engine pump, while 51.3 percent of the required energy for groundwater pumping was supplied by electric pump. Calculated total GHG emissions and the value of climate change indicator in the current condition were equal to 8.98 and 7.59 Milion kg CO2 eq , respectively. In order to achieve environmental sustainability and energy security, scenarios of replacing electric pumps and applying solar energy were examined. The results of the scenarios showed that diesel fuel wells had no significant effect on the reduction of greenhouse gas emissions, but the use of solar energy reduced them. GHG emissions, in comparison with the base scenarios, were decreased by 44.4% in June, July and August, respectively, by applying the scenario of using the solar pump in agricultural section. Therefore, it is preferred to apply policies in future planning to use renewable energies such as solar energy instead of diesel and electricity energy.

Introduction:Vinasse is a byproduct of the sugar industry. Sugarcane or Sugarbeet is processed to produce crystallinesugar, pulp and molasses. The latter isfurther processed by fermentation to ethanol, ascorbicacid or other products. After the removal of the desired product (alcohol, ascorbicacid, etc.) the remaining material is called vinasse. Vinasse is sold after a partial dehydration and usually has a viscositycomparable to molasses. Commercially offered vinasse comes either from sugarcaneand is called cane-vinasse or from sugarbeet and is called beet-vinasse. On average, for each liter of vinasse, 12 liters alcohol produced. Vinasse is a material with dark brown color and the smell of burned sugar, which is rich in potassium, calcium, magnesium, phosphorus and nitrogen. Materials and Methods:To determine the effect of vinasse and additive nitrogen and phosphorus on growth and yield of tomato, a factorial pot experiment was conducted at ZanjanUniversity in 2008. Two different plant nutrient including N and P and their combination (N+P) were added to vinasse with three different concentrations to form experimental treatments. In addition to these treatments, three control treatments with vinasse of different concentrations, but with no additive were also included in the experiment. Each treatment used with two different application methods (soil application and soil + foliar application).The experiment had 24 treatments, a complete randomized design and three replications. The vinasse used in this experiment was diluted with water 10, 20 and 40 times to make a nutrient solution of three different concentrations of tomato plant. The amounts of nitrogen and phosphorus that were added to vinasse were 224 and 62 mg/l, respectively. Phosphorus and nitrogen were applied to as super-phosphate triple and calcium nitrate and ammonium nitrate respectively. After being deployed to ensure complete installation of tomatoes in pots containing perlite (about 2 weeks after the transfer of seedlings tothe pots) treatments wereapplied to the pots. It should be noted that initially, three tomato seedlingswere planted in each pot at later stage after the plants were thinned to one plant per pot.Five months later after planting seedlings, fruits were picked and measured separately. At the end of the growth period, fruit yield, leaf and some quality characteristicsof fruit were measured. Results Discussion: The results showed that the effects of vinasse concentrations on fruit yield, dry matter content of fruit, dry weight of root and plant height were significant at p

Importance of renewable-energy resources because of scarcity, greenhouse-gas emissions, and their fundamental roles in production and sustainable development, has made governments to reduce energy consumption and improving energy efficiency. In this regard, targeting subsidies rule was running in Iran since 2010. Since energy additionaly to labor and capital is one of the important inputs in production, running this rule with increasing energy price, affects manufacturing industries due to the type of energy and industry. In this research, the impacts of price liberalization on electricity efficiency have evaluated. Partial adjustment model, generalized method of moment and energy intensity measure are applied to this purpose. Data are collected from Statistical Center of Iran during 1995-2013. The research innovations are: using a partial adjustment model in evaluating efficiency, assessment whole industrial groups, and the period of research. The results show that in 95 percent level of confidence, the Iranian manufacturing industries are significantly flexible for changing the use of electricity. But the electricity efficiency has gotten worse after running the rule. In general, apposite of expectations, targeting subsidies rule has failed to improve electricity efficiency at least in short run.