Liquorice is a perennial legume that grows principally in Asia, the Middle East and some parts of Europe. The sweet root extract is mainly used in the pharmaceutical, food and confectionary industries. It contains 400 compounds, including triterpene saponins and flavonoids, which are responsible for liquorice's bioactivities. The wastewater (WW) arising from the processing of liquorice can have negative environmental effects and must be treated before being discharged into the environment. Different WW treatment solutions are available. In the last years, increasing attention has been paid to the environmental sustainability of wastewater treatment plants (WWTPs). The present article discusses a hybrid biological (anaerobic-aerobic) and post-biological (lime-alum-ozone) WWTP, designed to treat 105 m3/day complex liquorice root extract WW for agricultural purposes. The influent chemical oxygen demand (COD) and biological oxygen demand (BOD5) were found to be 6000-8000 mg/L and 2420-3246 mg/L, respectively. With a biological hydraulic retention time of 8.2 days and no addition of extra nutrients, the WWTP reached a stable condition after 5 months. Over the course of 16 months, its highly efficient biological treatment reduced COD, BOD5, total suspended solids (TSS), phosphate, ammonium, nitrite, nitrate and turbidity by 86-98 %. However, the WW's colour proved resilient: only 68 % of the colour was removed by the biological treatment, necessitating a combination of biodegradation-lime-alum-ozonation processes in order to reach 98 % efficiency. Thus, this study reveals that liquorice root extract WW can successfully be treated and reused for crop irrigation.

Iran is the main watermelon producer in the world after China and Turkey. However, there is no practical information on which region, tillage and cultivation systems can achieve the most efficient watermelon production system in Iran. This study was conducted to assess the most efficient ways of watermelon production in three agroecosystems (cold, moderate, warm) of Iran using Data Envelopment Analysis. The data were collected from two tillage systems (reduced and conventional) and two groups of watermelon cultivations (conventional system and plastic film mulching system). Accordingly, twelve watermelon production systems were under the study including all inputs and outputs. Finally, an Analytical Hierarchy Process model was used to determine the best region and the best combination of cultivation and tillage systems for watermelon production. The technical and pure technical efficiencies of watermelon production systems were respectively 89%–100%. The Analytical Hierarchy Process model determined that the most efficient watermelon production systems were from combination of plastic film mulching system and reduced tillage in cold and moderate agroecosystem which reduced water and diesel fuel consumption by 500–2500 m3/ha followed by fertilizers by 100–150 kg/ha while efficiencies are enhanced by 20%–32%.

Background and Objectives: Among the various agricultural activities, working and driving with farm tractors in different weather conditions lead to fatigue and burnout. The objective of this study was to evaluate the sleep quality of farm tractors drivers in different weather conditions. Methods: Amongst tractor drivers in Behbahan, Eqlid, and Kavar, 90 participants (Kavar: 27; Eqlid: 33; Behbahan: 30) were selected. The required data was gathered using the demographic characteristics questionnaire and standard questionnaire Pittsburgh Sleep Quality Index (PSQI). We used Kruskal-Wallis and Post-hoc pairwise comparison tests to analyze the data (α = 0.05). Results: The results showed that there were no significant differences in sleep quality and sleep quality parameters between different region tractors drivers (P > 0.05); but there were significant differences in mental sleep quality (P = 0.001), in terms of delays in falling asleep (P = 0.02), going to sleep duration (P = 0.04) and between Kavar and Behbehan tractor drivers, and also there are significant differences in going to sleep duration (P = 0.04) between Kavar and Eqlid tractor drivers. Conclusion: Working in critical cold weather (like nights in Eqlid) or critical hot weather (like noon in Behbahan) should be strongly forbidden by providing with a suitable working schedule especially while tractor drivers without driver’s cabin. Drivers’ cabins safeguards drivers against temperature, wind and dust, and, therefore increase their comfort and sleep quality.

The present study was undertaken to determine the effects of ultrasonic factors (acoustic power and sonication time) and substrate mixture (tomato waste and cow manure) on the degradability of lignocellulosic structures, removal of pollutants and solids of feedstock, and improving bio-H 2 production. Integrating multivariate regression modeling and structural equation modeling could achieved this goal. The results showed that the substrates had significant effect on improving the feedstock characteristics at the beginning of fermentation, in which tomato waste required stronger pretreatment. Further, the acoustic power showed more significant effect than sonication time. Analyses showed that the most effective characteristics for bio-H 2 fermentation were BOD removal, COD removal and cellulose content removal, in which removal of BOD and COD had the highest effect from the ultrasonic pretreatment factors, and cellulose content removal had the highest effect from tomato waste amount in the mixture. However, to optimize bio-H 2 production, substrate mixtures needed ultrasonically pretreatment, in which tomato waste required a stronger pretreatment. The ultrasonic power of 0.1 W/mL at sonication time of 15 min were sufficient to optimize bio-H 2 , and no need to consume extra energy. In the suitable conditions of pretreatment and substrate mixture, removal of lignin, cellulose and hemicellulose contents increased 57.67%, 24.38% and 38.7% higher than those of a control system, which resulted in an increase of 6% bio-H 2 production.

IntroductionToday, diesel engines provide the main power source for the world equipment e.g., common propulsion generators in industry and agriculture. These engines are widely used due to their high combustion efficiency, reliability, compatibility, and cost-effectiveness. However, diesel engines are one of the most critical consumers of fuel which in turn causes some environmental pollution. One of the convenient and low-cost ways to reduce the pollution of these engines is dual-fuel mode and the use of gaseous fuels as an alternative fuel. This study investigated the effect of blending CNG and LPG with neat diesel in dual-fuel mode. Besides, the variation in engine coolant temperature on engine performance characteristics was experimentally studied.Materials and MethodsThe experimental apparatus consisted of a stationary, four-stroke, naturally aspirated, water-cooled, single -cylinder compression ignition engine. To control the engine load, an electrical dynamometer was made using a 7.5 kW three-phase generator and coupled to the engine as a cradle. A load cell was used to determine the force applied to the generator. The engine speed was monitored continuously by a tachometer. Fuel consumption was measured by using a weight method. A thermostat with variable temperature was used to control the temperature of the engine coolant. To measure the mass flow of air entering the cylinder, an airbox with a sharp edge orifice was used. For this study, factorial experiments in the form of a randomized complete block design with three replications were utilized to analyze the data statistically. The studied parameters were three levels of fuel ratio (100% diesel, 20% diesel and 80%+/- 2% CNG, 20% diesel and 80%+/- 2% LPG), 11 engine speeds (1500 to 1600 rpm with 10 rpm intervals), and three engine coolant temperatures (50, 60, and 70 degrees C). All experiments were conducted in the governor control mode.Results and DiscussionThe results showed that the torque, brake power and brake mean effective pressure (BMEP) in the diesel-CNG mode at all engine speeds and in the diesel-LPG mode at low engine speeds significantly increased compared to pure diesel. The increases in these parameters in the diesel-CNG mode were 18.67%, 19.56% and 19.85%, and in the diesel-LPG mode were 14.02%, 13.86% and 14.2%, compared to those related to the pure diesel, respectively. This increase could be due to the high calorific value of gas fuels and improvement of combustion inside the cylinder due to the formation of homogeneous charge. At low engine speeds, the reductions in the brake specific fuel consumption (BSFC) and brake specific energy consumption (BSEC) for coolant temperature 60 degrees C were 11.21% and 10.77%, compared to coolant temperature 50 degrees C, respectively. Also, the BSFC and BSEC for diesel-CNG dual-fuel mode decreased by 8.12% and 10.81%, respectively. These values for the diesel-LPG dual-fuel mode were 5.4% and 2.4%, respectively. The brake thermal efficiency (BTE) also showed a significant increase at high speeds and when using the dual-fuel operational mode. However, raising the coolant temperature due to reducing the heat losses of the engine increased the BTE. The increases in BTE for coolant temperatures 60 and 70 degrees C were 7.19% and 4.37%, compared to the coolant temperature of 50 degrees C, respectively. When using the engine in dual-fuel mode, the volumetric efficiency due to reducing the air ratio showed a significant reduction. These diesel-CNG and diesel-LPG dual-fuel mode values were 20.31% and 24%, respectively. Furthermore, raising the coolant temperature diminished the volumetric efficiency. The reduction in volumetric efficiency for the coolant temperatures of 60 degrees C and 70 degrees C were 6.84% and 19.91% compared to the coolant temperature of 50 degrees C, respectively.ConclusionThe following conclusions can be deduced based on this study:The use of gaseous fuels as the main fuel and with a small amount of diesel in compression ignition engines is possible and improves the engine's performance characteristics.In the diesel-CNG mode, torque, brake power and BMEP at all engine speeds and in the diesel-LPG mode at low engine speeds significantly increased compared to pure diesel because of improved combustion inside the cylinder.At low engine speeds, increasing the coolant temperature reduced the BSFC and BSEC. Also, in the dual-fuel mode compared to the engine with baseline diesel fuel, the BSFC and BSEC were significantly lower due to the higher calorific value of gaseous fuels and higher power generation.The BTE at high engine speeds and when the engine was in dual-fuel mode showed a significant increase. Also, increasing the coolant temperature due to reducing the heat losses of the engine increased the BTE.When using the engine in the dual-fuel mode, due to the volume of air replaced by the gas, the volumetric efficiency showed a significant reduction. Also, raising the coolant temperature diminished the volumetric efficiency.Overall, it can be stated that the use of a diesel-CNG dual-fuel mode with a coolant temperature of 60 degrees C at entire engine speeds has the best outputs on the performance and combustion characteristics of the engine.

Land evaluation is the process of land performance predictions over time based on land uses and soil features. Traditional methods in determining soil features are proved to be time-consuming and costly. Therefore, in order to overcome these limitations, a simpler automated method using the image segmentation was developed in this study. The method was designed by integrating dynamic region merging and genetic algorithm. An area index was calculated for each soil profile using the automated method. It was used to present the amount of soil coarse particles and thereupon to determine the rating value of text-structure. Using the method, the mean intersection over union of above 0.7 was obtained for detecting the coarse particles which confirms its suitability. Data analysis showed that (a) compared to the Storie-land index (R-2 = 0.71), the Square root-land index was more correlated to the harvest index (R-2 = 0.73), and (b) comparing to manual methods, not only the automated text-structure had a higher correlation with the harvest index (R-2 = 0.64) but also it decreased the determination time (>3.75 times). Furthermore, among the models developed by response surface methodology for estimation of soil features, the developed model for estimation of soil lime showed the highest accuracy (R-2 = 0.89). In conclusion, since the developed method is more accurate, more economic and faster than the usual manual methods, it can be widely used in land suitability evaluation.

In Iran, allocating tractors and agricultural machinery to regions that have different characteristics has been a challenge. This study was carried out in order to develop an optimal and practical model for distribution of agricultural machinery throughout the country. Gini coefficient was used in order to investigate whether current status of tractor distribution is suitable. This coefficient confirmed that the current tractor power distribution is not appropriate since there were no relationships between Gini coefficient of distributed machinery power and crop production or farm area. Accordingly, two main techniques were applied to develop a suitable agricultural machinery distribution pattern; i.e. a Fuzzy Analytical Hierarchy Process (FAHP) and a Weight Restriction Data Envelopment analysis (WR-DEA) technique. A power distribution category was defined in order to show qualitatively how much machinery power should be sent to each province. The outputs of both FAHP and WR-DEA models showed that three and nine provinces need ‘much more power’ and ‘more power’, respectively, while four and three provinces need ‘absolutely no more power’ and are ‘currently suitable’, respectively. The sensitivity analysis revealed that none of the developed models was sensitive to the weights defined by a panel of experts. The similarity of the results obtained from both models implies that the provided agricultural machinery distribution pattern is reliable and can be used in the country.

In the present study, effect of biogas recirculation on slurry characterization, microbial activity and biogas purification were studied. Two digester units, one for control treatment and another equipped with a gas compression system for recirculation treatment, were designed and constructed. Experimental results showed that the recirculation system could improve the mixing process with a little energy consumption. The slurry analysis during the digestion indicated that (i) in the recirculation treatment, TC, TN, COD and BOD had a step up after the first injection and then decreased while they continuously decreased for the control treatment, (ii) amounts of TC/TN appeared that the carbonated compounds increased more than nitrogenous compounds for recirculation treatment, and (iii) the biogas recirculation decreased pH. The biogas analysis showed that the biogas recirculation could create a suitable environment for growing the anaerobic microbes (up to 21%) in the digester that not only decreased some of the harmful compounds like H2S (about 0.21 %VOL) but also increased the CH4 concentration (up to 11 %VOL). Significant correlations between the anaerobic microbial communities and CH4 (r=0.9), CO2 (r=−0.91), H2S (r=−0.89), CO (r=−0.8) and O2 (r=−0.71) for recirculation treatment documented the biogas recirculation can improve the environmental conditions for anaerobic microbial life and is a very convenient way for biogas purification.

Jahrom is one of the warm grain production areas in southwestern Iran, and the winter wheat-summer maize double-cropping system dominates the region. The ecological sustainability and environmental behavior of these two annual farming systems in the region need critical attention. In the present paper, emergy evaluation was introduced to explore the impacts of the wheat and maize cropping systems on the environment. In the emergy analysis, renewable and non-renewable inputs besides purchased fuel, goods, labor and services were considered. 193 farmers were chosen for the study using simple random sampling without replacement. The results revealed that the unit emergy value of wheat and maize were 4.05E+05 sej/J and 4.23E+08sej/J, respectively. The environmental loading ratio of maize was much higher than that of wheat cropping, i.e. 570 vs. 115. The investment ratio of wheat was higher than that of maize, indicating that wheat is more dependent on the purchased materials than "free indigenous" emergy inputs. Nevertheless, the analyses of different scenarios indicated that unit emergy value and all the sustainability ratios of the systems can be enhanced by around 20–55% via using appropriate water, nutrient, and agronomic management measures. It is recommended that the maize production should be continued with much more care, especially on the nitrogen utilization and water consumption, compared to the wheat production in this warm area of the country.

Agricultural production inevitably poses adverse impacts on local environment, while the collective action of farmers can also contribute positively to sustainable resources management. The structural component of economic actors' integration is often related to social capital. This study analyses the impacts of farmers' socioeconomic conditions on energy use and life cycle environmental impacts of Iranian rice production. Based on the local socio-economic status and life cycle assessment, some types of social capital groups are suggested to achieve cooperative rice production with lower burden on the environment. Four social capital groups, namely "water, fertilizer and pesticide users", "consolidated farming", "new technology users" and "micro-finance", are suggested according to the life cycle assessment. The members of each social capital group were determined by data envelopment analysis to guarantee that each social capital group moves toward better rice production methods with lower burden on the environment. Technical efficiency of farmers was determined by data envelopment analysis models which in turn help us identify core and target members of each social capital group. The results show that the lowest energy input for rice production is 28,000 MJ/ha, which appeared in groups with medium aged farmers who have medium farming experiences. The sample farmers with higher net income, larger farms and participating in extensional classes contribute to mitigate total energy consumption of rice production. The life cycle assessment confirms that those socio-economic groups consuming lower energy also impose lower burden on the environment.

The nitrate complexes of group 12 elements with a tridentate Schiff base ligand (L = (E)-N1-((E)-3-phenylallylidene)-N2-(2-((E)-((E)-3-phenylallylidene) amino)ethyl) ethane-1,2-diamine) were synthesized via sono-chemical process and characterized by various physical and chemical methods. The structural analysis of the zinc nitrate complex by single crystal X-ray diffraction analysis shows that the central atom is seven-coordinated by three nitrogen atoms from the Schiff base ligand as well as four oxygen atoms from two different nitrate anions. The geometry around the metal center can be described as a distorted pentagonal bipyramid. The crystal packing analysis of zinc nitrate complex indicates that the intermolecular interactions related to nitrate groups plays the essential role in the orientation of supramolecular structure. Iiirshfeld surfaces (HS) and their corresponding fingerprint plots (FP) have been also used for further investigation of crystal structure of zinc nitrate complex. Furthermore thermal analyses (TG/DTG) of three nanostructure complexes were carried out and discussed. Finally, direct thermolysis of zinc and cadmium nitrate complexes in air atmosphere led to the production of zinc and cadmium oxide nanoparticles.

Background: Musculoskeletal disorders (MSDs) are usually caused by bad working postures and habits. There is a great demand to correctly estimate laborers' work-related musculoskeletal disorders (WMSDs) during physically intensive works. This study aimed to suggest a practical solution with ergonomic principles and time studies on the reduction of WMSDs for the apple harvesting laborers in Sepidan gardens at the Fars Province, Islamic Republic of Iran (Iran). Methods: Prevalence of MSDs was evaluated by the Nordic Standard Questionnaire surveys and the laborers' workload was assessed by the rapid entire body assessment postural analysis tool. A stop watch time study method was employed to estimate rest time allowances. Data from the time study was also recorded by a questionnaire validated from a panel of experts. Thirty laborers from two age groups: a young (20-35 years of old) and old (36-55 years old) were sampled from 10 gardens. Results: The stop watch time study revealed that the frequencies of apple harvesting works were 95 vs. 119 times for the old group and young one, respectively. The prevalent disorders were related to specific body regions such as the lumber, knee, neck and shoulder areas. The percentages of disorders were significantly reduced when ergonomically corrected postures were applied with suitable rest time allowances. Conclusion: Fruit harvesting works may need to improve their work-rest time intervals to prevent WMSD developments and productivities with time managements. With a correct estimation of the desired number of laborers, apple harvesting jobs can be performed on time, and by implementing appropriate ergonomic postures, occupational health and safety problems can be lessened in the apple harvesting workers.

Conservation tillage systems and residue management as well as nitrogen application are the effective factors on soil properties and crop yield. This study investigated the influence of these factors on the soil properties and winter wheat yield in the warm, semi-arid region of Jahrom, in south of Iran. The variables were residue management, i.e. keeping (R1) and burning (R2) previous corn residue beside two tillage systems, i.e. chisel plowing (T1) and moldboard plowing (T2); and three levels of nitrogen application i.e., F1 = 0 kg/ha, F2 = 100 kg/ha and F3 = 150 kg/ha. The result revealed that the highest total organic carbon and nitrogen content were obtained when chisel applied in the retained crop residue. But, soil BD was lower with moldboard plowing. It was indicated that chisel plowing can lead to highest yield when combined with retained residue and 150 kg/ha nitrogen.

Background Several thousand worker injuries and fatalities worldwide per year is the consequence of agricultural activities especially working with farm tractors. The aim of this study was to determine current levels of farm tractors drivers' safety attitudes in Iranian agriculture besides type and severity of tractor-related injuries. Method: Socio-demographic properties of a sample of 281 tractor drivers and their injuries were investigated using face to face interview. The severity of injuries were also determined. The drivers' attitudes toward safety issues were analyzed by exploratory factor analysis. Results: The results revealed that drivers aged 30-45 years had higher rates of injuries. Most of injuries were moderate (41%) occurring due mainly to oily surfaces on the tractor or implements, carelessness or fatigue during the work. The low-income group had also higher injuries since the drivers in this group work with no regular work-rest schedule and they usually work with old tractors equipped with unsafe facilities. Those that do comply with safety measures are likely to have fewer exposures to unsafe work practices and consequence injuries. Further education of tractors drivers in various aspects of farm safety besides enforced regulations to adjust safety issues are the possible approaches to prevent tractor-related injuries.

The sustainability of agricultural production is one of the most important issues in today’s farming. A combination of analytical hierarchy process and fuzzy modeling was used with the combination of geographical information system (GIS) to develop a reference base that evaluates sustainability of winter wheat within the Fars province, Iran. Bio-physical (soil and climatic, agronomic, and machinery), and socio-economic factors (benefit-cost ratio, farmers’ knowledge and experience) were taken into consideration in the assessments. Results showed that amongst bio-physical, soil salinity and annual precipitation were the main obstacles of the sustainable production. The total land suitability scores represent “medium” to “very high” levels of sustainability. The highest sustainability score was obtained from the socio-economic category, followed by machinery and agronomic categories. Over-fertilization and high water consumption were found as the main reasons of low agronomic sustainability. Almost all the sustainability scores were higher in the central region of the study area while the overall sustainability was “medium” in more than half of the area. The extension trainings, prevention laws and government provided credit to buy necessary farm machines are recommended to reduce fertilizer, pesticide and water consumption. The results also showed that larger farm sizes, coupled with suitable farm machinery, particularly on smaller farms are expected to enhance machinery sustainability scores. The study also concluded that ANFIS is as a capable tool to predict sustainability indices obtained from GIS. The developed ANFIS models could estimate sustainability indices with minimum errors to be amended by GIS.

Although a set of appropriate livelihood alternatives has already been developed to approach sustainable rangeland management (SRM), determining an appropriate livelihood model for supporting policy makers still remains to be a challenge. Livelihood alternatives are affected by multiple factors such as livelihood capital, vulnerability contexts as well as policies, institutions and processes which can be identified by stakeholders from different perspectives. Accordingly, determining appropriate livelihood alternatives is a multifaceted challenge that requires multi-criteria decision-making (MCDM) techniques. This paper aims to review MCDM methods that have the potential to be applied in SRM. It discusses how different MCDM techniques can be used and which techniques are well matched to determine appropriate livelihood alternatives. First, it justifies the need for decision support systems followed by an explanation of the most common MCDM techniques. Among them, two techniques, namely analytic hierarchy process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), are found to be the most suitable MCDM in the case of SRM. Furthermore, based on the reviews on different hybrid approaches, AHP–TOPSIS is introduced as a superior approach to select appropriate livelihood alternatives. Accordingly, AHP is introduced to elicit the relative importance of livelihood criteria and TOPSIS is employed to provide a score for livelihood alternatives. As a conclusion, the application of AHP–TOPSIS approach is proposed where many decision criteria, alternatives and stakeholders are involved. Subsequently, a methodological framework to determine a livelihood model is also developed. This study concludes that, as well as recognizing the theory of appropriate livelihood alternatives, the application of MCDM techniques can be further pursued toward devising a workable policy framework for SRM. At the end, we have elaborated future methodological issues to be considered when selecting feasible alternatives to resolve the current challenges in SRM.

In order to reach suitable and effective performance of farm machines, on time agricultural operations is important.Also, using human resources productively and its productive enhancement needs appropriate planning.In the current study, the life and repair distribution functions of three tractors were estimated, and then, the necessary number of repairmen was determined in such a way that supplies the minimum waiting time to repair in one hand, and maximum human productivity is obtained in the other hand.Three tractors were under the study; i.e. two Massey Ferguson 285 and one Massey Ferguson 399.The tractors working data were gathered for 1100hours.Then, the Monte-Carlo simulation method was applied to simulate tractors working conditions for around 3500hours to have more reliable estimation of life and repair distribution functions.The results showed two functions for life and repair times; i.e.Exponential for life and 2-parameter Weibull for repair.Furthermore, two repairmen should be employed to have minimum waiting time to repair and maximum economic benefits from the view point of useful tractors working hours.

Greenhouse gas (GHG) mitigation in agriculture should be approached, among others, through changes in farm management and technology use. The application of new GHG mitigation technologies are essential to promote a cleaner environment. This is critical since not all new technologies are environmentally friendly. To understand whether and to what extent such technologies mitigate GHG, this survey study was conducted to measure the amount of the dynamic energy consumption and productivity growth of pomegranate production during 2009-2015 in the Fars province, Southwest Iran. Dynamic DEA models were employed for the efficiency analyses. The data were gathered from pomegranate gardeners through questionnaires by face-to-face interviews. The validity and reliability of the questionnaires were tested and confirmed respectively through a pilot study and Cronbach's alpha. Using simple random sampling method, 55 pomegranate gardeners were chosen for the survey. The dynamic DEA revealed that our gardeners had the best performance in 2013, 2014 and 2015. The average energy consumption was 42,230 MJ/ha to produce 17,300 kg/ha pomegranate. The highest output-input energy ratio was also obtained in 2013, 2014 and 2015 of 1.013. The most efficient gardeners consumed more renewable energy especially in the form of farm yard manure. Accordingly, the gardeners with the least efficiency should enhance pomegranate yield and reduce the extra energy inputs of around 10,000 kg/ha (58% of average) and 25,000 MJ/ha (59% of the average), respectively. Malmquist index showed that the best efficient gardeners had annual positive technology change of 8.3%. Statistical analyses confirmed that each positive percentage of technology change reduces the energy input by 710 times and CO2 emission mitigation by 634 times meaning that the gardeners used some energy efficient technologies that lead to lower GHG emissions. The technology change can be predicted by some of the socio-demographic attributes of the gardeners such as farming experience, net income and participating in extensional classes. The study concludes that highly efficient pomegranate production besides new technology use policies would ultimately contribute to the robust climate change mitigation from this sector. (C) 2017 Elsevier Ltd. All rights reserved.