Fatemeh Ghorbani Piralidehi,; Kumars Zarafshani; Farzad Jalilian
Volume 9, Issue 3 , April 2012
Abstract
Integrated Pest Management (IPM) has been introduced as an appropriate environmental strategy to control pest populations. The purpose of this descriptive correlational study was to determine the factors influencing the knowledge, attitude, skills, and aspirations (KASA) among a sample of orchard farmers ...
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Integrated Pest Management (IPM) has been introduced as an appropriate environmental strategy to control pest populations. The purpose of this descriptive correlational study was to determine the factors influencing the knowledge, attitude, skills, and aspirations (KASA) among a sample of orchard farmers participating in IPM training at a farmer field school (FFS). From a total of 130 participants, 97 orchard farmers were randomly selected as the sample size. A researcher-made questionnaire was designed using literature review and informal interviews with FFS participants outside the population. A panel of experts approved the content validity of research instrument. An alpha level of 0.86 showed sufficient reliability of the questionnaire. The results of step-wise regression analysis revealed that participating in FFS, farming experience, yield, trust, and social status affected orchard farmers’ IPM knowledge. Moreover, farmers’ attitudes towards IPM were influenced by knowledge diffusion, creativity, and access to horticultural equipment. In addition, knowledge diffusion, yield, membership in farmer cooperatives, and being creative affected orchard farmers’ skills in IPM. Finally, job satisfaction, age, and knowledge diffusion influenced farmers’ aspirations towards IPM. The result of this study has implications for IPM-FFS policy-makers. Developing FFS sites and actors in the province, conducting orientation classes in IPM for contact farmers, and extending financial support to IPM are all recommended.
Hamed Mansoori,; Eskandar Zand,; Morteza Tavakoli; Mohammad Ali Baghestani
Volume 9, Issue 3 , April 2012
Abstract
In order to study the effect on sunflower and cotton of the residue of some sulfonylurea herbicides, two randomized complete block design studies were conducted with ten treatments in four replications for both of plants. Treatments included: sulfosulfuron (Apirus), idosulfuron+mesosulfuron (Chevalier), ...
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In order to study the effect on sunflower and cotton of the residue of some sulfonylurea herbicides, two randomized complete block design studies were conducted with ten treatments in four replications for both of plants. Treatments included: sulfosulfuron (Apirus), idosulfuron+mesosulfuron (Chevalier), chlorsulfuron (Megaton), sulfosulfuron+ metsulfuron methyl (Total), idosulfuron+mesosulfuron+ mefenpyr (Atlantis) where all of the herbicides were used in three doses, with a no-herbicide control. Soil was sprayed with the herbicides and the treated soils were transferred to the greenhouse after four months, and sunflower and cotton were planted in pots containing these soils. The length and dry weight of different plant organs (root, stem and leaf) and total dry weight were measured at the four-leaf stage. The results showed that the treatments had negative effects on most of the measured characteristics in sunflower and sulfosulfuron+ metsulfuron methyl and chlorsulfuron at the highest dose (44 and 22.5 g ai ha-1, respectively) had the most harmful effects on the sunflowerand reduced dry weight by 82.97% and 70.31%, respectively, in comparison with the control. Only the height and root length of cotton had been affected of the herbicides and sulfosulfuron+ metsulfuron methyl and chlorsulfuron at the highest dose had the greatest negative effects on the height and root length of cotton. In attention to the results obtained, we can conclude that sunflower is probably more sensitive than cotton towards sulfonylurea herbicide residue.
Zahra Kayhomayoun; Hamid Reza Nassery; Mohammad Nakhaei
Volume 9, Issue 3 , April 2012
Abstract
For identifying sources of groundwater salinization in Lenjanat Plain, samples were seasonally collected from groundwater, surface water and industrial wastewater. The results of field and laboratory measurements show a gradual increase in major (Na, Ca, Cl, SO4) and minor (Li,Br,Sr،I,Ba،F,Si) elements ...
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For identifying sources of groundwater salinization in Lenjanat Plain, samples were seasonally collected from groundwater, surface water and industrial wastewater. The results of field and laboratory measurements show a gradual increase in major (Na, Ca, Cl, SO4) and minor (Li,Br,Sr،I,Ba،F,Si) elements through groundwater flow direction. Electrical conductivity varies between 561 and 11390 μS/cm. The chloride ion, as an indicator of groundwater salinization, is highly correlated with EC and the elements Mg, Ca,Brand Sr. Certain ratios, the saturation index and geochemical graphs indicate that both the dissolution of evaporation deposits (halite and gypsum) and cation exchange are the most important processes affecting the chemical composition of groundwater. Mass ratios of conservative elements Cl/Br for groundwater samples in Lenjanat plain range from 329 (at the borders) to 4492 (center of the plain). These data confirm the reported Cl/Br ratios for groundwater affected by the dissolution of evaporation deposits but overlap with range of Cl/Br ratios for domestic sewage effluent groundwater.
Taraneh Sharmad; Mohammad Hossein Adabi,; Abdolreza Karbassi; Hossein Bageri
Volume 9, Issue 3 , April 2012
Abstract
In the present study depositional temperature, diagenetic type and major climatic changes are investigated using oxygen and carbon stable isotopes. For this purpose, a sediment core (140 cm long) of 12 Km distance from the coast (near Langroud city), was collected from the southern Caspian Sea.A sedimentation ...
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In the present study depositional temperature, diagenetic type and major climatic changes are investigated using oxygen and carbon stable isotopes. For this purpose, a sediment core (140 cm long) of 12 Km distance from the coast (near Langroud city), was collected from the southern Caspian Sea.A sedimentation rate of 0.9 cm/year was obtained based on a 210Pb and 137Cs isotope study of the sediment core. The depositional temperature and diagenetic type were obtained based on Mass Spectrometry analysis of sediment samples. The oxygen-carbon isotope study indicates a very low depth of burial diagenesis. Water temperature based on the heaviest oxygen isotope value with least alteration, shows around 21ºCduring sedimentation, (120 years ago) while CTD results during sampling show the same result, so it seems that there have been no major climatic changes in the study area.
Abbas Ghodsi,; Ali Reza Astaraei; Hojat Emami,; Mohammad Hadi Mirzapour
Volume 9, Issue 3 , April 2012
Abstract
A field experiment at Qom province was conducted to study the effects of different amounts of nano iron oxide powder and urban solid waste compost coated sulfur (USWCS) on yield and yield components of sunflower plants in a saline-sodic soil, in a randomized complete block design with factorial arrangement ...
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A field experiment at Qom province was conducted to study the effects of different amounts of nano iron oxide powder and urban solid waste compost coated sulfur (USWCS) on yield and yield components of sunflower plants in a saline-sodic soil, in a randomized complete block design with factorial arrangement with three replications. Treatments were two levels of urban solid waste compost coated sulfur (0 and 15 ton/ha) and two levels of nano iron oxide powder (0 and 20 mg/kg) applied to plots of 4 m2 and sunflower plants were sown. The results showed that the use of nano iron oxide and USWCS increased grain yield by 4 and 22 percent, respectively, compared to the control. The maximum increase in dry matter yield was observed by combined use of 15 (ton/ha) USWCS and 20 (mg/kg) nano iron oxide. Application of nano iron oxide powder significantly increased the plant height, head diameter and 1000 seed weight of sunflower plants. This increasing trend with the use of USWCS was also observed in plant height, head diameter and 1000 seed weight by 8, 18 and 15 percent, respectively, compared to control.
Mahmoud Ahmadi; Hanieh Mirhaji
Volume 9, Issue 3 , April 2012
Abstract
Thermal stress in plants is any temperature increase above the threshold level for a period of time which causes immutable damage in plant growth. At very high temperatures associated severe cellular damage and cell death may occur within a few minutes as a result of disassembling the cell structures. ...
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Thermal stress in plants is any temperature increase above the threshold level for a period of time which causes immutable damage in plant growth. At very high temperatures associated severe cellular damage and cell death may occur within a few minutes as a result of disassembling the cell structures. Direct damage from heat stress includes disruption of the protein structure and an increase in fluidity of cell membranes, as well as indirect damage. The result of these disorders is damage to the plants that prevents growth. In the current study, the occurrence time of thermal waves or some climatic phenomena in Qazvin Province were studied over a 25-year period (1982-2007) and an assessment was made of the impact of thermal stress on corn plant growth. The results showed that the highest thermal waves were seen in the months of June, July and August in the years 1985, 2000 and 2001. More heat waves occurred during July in the years 1983, 1995, 1997, 2003 and 2006 while in August more heat waves were experienced in 1983, 1983 and 2005. Over this 25-year period, only on 10 days in June, 63 days in July and 50 days in August did the temperature reach above 38 degrees when corn plant is under stress. In these three months, more negative impact was found in July that caused crop quality reduction or even the death of the plant. When thermal waves increased and rose above than plant endurance threshold, this had a negative impact on production and caused the production rate to reduce or, in some cases, collapse completely.
Zahra Razmpour,; Hossein Kermanian; Omid Ramezani,; Saeed Mahdavi; Mehdi Rahmaninia
Volume 9, Issue 2 , January 2012
Abstract
Recycling is a promising approach for rescuing the earth from recoverable solid waste. Among different wastes, paper plays an important role. The effects of wastepaper recycling times on the properties of recycled paper have always been considered but less attention has been paid to semi-chemical papers. ...
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Recycling is a promising approach for rescuing the earth from recoverable solid waste. Among different wastes, paper plays an important role. The effects of wastepaper recycling times on the properties of recycled paper have always been considered but less attention has been paid to semi-chemical papers. In this study, the effect of the recycling times of NSSC wastepaper on their WRV (Water Retention Value), hornification of fibers, tensile strength index, burst strength index and tear strength index was investigated. Results indicated that successive recycling of NSSC wastepaper presents an identical behavior to successive recycling of chemical waste papers. The WRV, tensile strength index, burst strength index and tear strength index decreased and the hornification of fibers increased.
Mohammad Sadegh Ebrahimi,; Khalil Kalantri,; Ali Asadi,; Seyed Hamid Movahed Mohammadi; Iraj Saleh
Volume 9, Issue 2 , January 2012
Abstract
Land consolidation programs in Iranian rice fields follow numerous targets of which the most important is a decrease in the consumption of chemical inputs: chemical fertilizers and resultant chemical toxicity in paddy fields. The goal of this research is the comparison of input consumption sustainability ...
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Land consolidation programs in Iranian rice fields follow numerous targets of which the most important is a decrease in the consumption of chemical inputs: chemical fertilizers and resultant chemical toxicity in paddy fields. The goal of this research is the comparison of input consumption sustainability in traditional and developed paddy fields in Iran (a case study of Gilan Province). The research was conducted in the form of a survey study. The necessary data for this research collected squarely by 188 farmers of land consolidation programs in Gilan Province were sampled using a stratified random sampling procedure. Data was collected through a questionnaire. The reliability of the questionnaire was obtained by calculating the cronbach alpha coefficient (0.65) after conducting a pilot study. The t-test of the test results showed that in two groups of farmers, the farmers of developed paddy lands used significantly more animal manure than traditional land paddy fields. Also, in terms of the consumption of chemical fertilizers, there are significant differences in the two communities and the farmers of developed paddy lands used significantly more urea fertilizer in paddy fields, but rice farmers in traditional paddy fields overall have a greater chemical toxicity consumption, especially of chemical insecticides, than equipped paddy fields farmers.
Sanaz Shoghi Kalkhoran,; Amir Ghalavand; Seyed Ali Mohammad Modares Sanavi
Volume 9, Issue 2 , January 2012
Abstract
In order to study the quantitative and qualitative characteristics of sunflower (Alestar hybrid) under the effects of bio fertilizer and winter wheat as a green manure,in combination with the integrated nitrogen sources (chemical-farmyard manure, FYM), an experiment was carried out on experimental farm ...
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In order to study the quantitative and qualitative characteristics of sunflower (Alestar hybrid) under the effects of bio fertilizer and winter wheat as a green manure,in combination with the integrated nitrogen sources (chemical-farmyard manure, FYM), an experiment was carried out on experimental farm at the Faculty of Agriculture of Tarbiat Modares University in Tehran (Iran) during 2008. The experimental design was a split plot in a randomized complete blocks design with three replications in which seven fertilizer treatments, namely F1 (100% FYM), F2 (75% FYM + 25% chemical), F3 (50% FYM + 50% chemical), F4 (25% FYM + 75% chemical), F5 (100% chemical), F6 (50% FYM + 50% chemical + green manure) and F7 (75% FYM + 25% chemical + green manure), were randomized to the main plot units and two levels of bio fertilizer I1 (inoculation) and I0 (control) to the sub-plot units. The results revealed that for grain and biological yield, yield components in integrated systems was significantly more than in organic and chemical systems. The highest grain yield (3034.5 kg/ha), head weight (90.06 g), head diameter (19.40 cm), 1000 seed weight (67.99 g) and seed number in head (925.5) were obtained in the F6treatment (F6>F3>F4>F7>F2>F5>F1). Inoculation of bio fertilizer improved the grain yield and yield components, oil and protein content and the oil quality of sunflower compared with untreated plants. Saturated fatty acids decreased significantly, while unsaturated fatty acids (linoleic acid and oleic acid) increased in response to raising the organic manure and using bio fertilizer.
Jafar Kambouzia; Shahrad Novin
Volume 9, Issue 2 , January 2012
Abstract
As the population of the world increases, the demand for food, food security and, hence, maximizing yield is becoming a challenging issue for modern agriculture. Over the last decades, the application of chemicals like fertilizers, pesticides and herbicides has increased dramatically. Despite improvements ...
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As the population of the world increases, the demand for food, food security and, hence, maximizing yield is becoming a challenging issue for modern agriculture. Over the last decades, the application of chemicals like fertilizers, pesticides and herbicides has increased dramatically. Despite improvements in plant breeding programs reducing the demand for chemicals, herbicide use is still increasing worldwide. According to the literature, continuous use of heavy doses of chemicals is encouraging the development of resistance in different weed species and endangering the ecosystem. Consequently, resistance development among weeds to herbicides is of great concern. Now, some research efforts are concentrated on finding some natural extracts to control this threat, thereby reducing the use of herbicides in future. In general, the term allelopathy refers to the chemical interaction between plants in which one plant may be affected by another plant’s chemical extracts. An experiment was designed and conducted to examine the effects of some extracts obtained from three plants (wheat, barley and rapeseed) on the number and speed of seeds germinated as well as the early growth of 3 weed species (barnyard grass, lambs quarters and redroot amaranth) and one goal crop (tomato). In addition, distilled water was used as a control treatment. The experiment was conducted under two conditions: laboratory and glasshouse, based on a randomized complete block design. Collected data were exposed to advanced statistical analysis including ANOVA and multivariate analysis (PCA). The results indicated that some extracts can reduce the germination and early growth of certain weeds and crop, for example weed extract on barnyard grass, rapeseed extract on tomato and redroot amaranth. Thereby the application of these extracts may effectively control some weeds such as barnyard grass and redroot amaranth. However, some other extracts positively affected the rate and speed of germination of some plants. For example, rapeseed extracts increased barnyard grass germination and early growth. This result indicated the caution of using of specific extracts on plants.
Ebrahiem Hoshiari; Alireza Pourkhabbaz
Volume 9, Issue 2 , January 2012
Abstract
Waterbirds are exposed to many contaminants. Heavy metals such as lead and cadmium are known as the most important toxic pollutants in an aquatic ecosystem. Poisonous elements had never been reported in larus birds (Larus heuglini) of the Iranian Mangrove Biosphere Reserve. The aim of this investigation ...
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Waterbirds are exposed to many contaminants. Heavy metals such as lead and cadmium are known as the most important toxic pollutants in an aquatic ecosystem. Poisonous elements had never been reported in larus birds (Larus heuglini) of the Iranian Mangrove Biosphere Reserve. The aim of this investigation was to measure levels of metal concentration in liver, kidney and muscle tissues of larus in the Mangrove Biosphere Reserve. To this end, fifteen birds were collected on November 2010. The results indicated that the average lead, cadmium and zinc levels were highest in kidney and lowest in muscle. There was no significant difference in tissue concentrations of Cd and Pb between males and females. In the present study, levels of Cd and Pb in tissues showed no change with age. However, the concentrations of trace elements in Larus heuglini were generally comparable to values reported in other studies. The results of the investigation do not show an excessive exposure to cadmium, whereas some interesting data have emerged in the case of lead. The concentration of the latter in the liver and the kidney of larus seem to suggest the possibility of recent exposure. Kewords: Metals, Mangrove Biosphere, Ecosystem, Larus heuglini.
Mohammad Bitarafan,; Hasan MohammadAlizadeh,; Eskandar Zand; Bejan Yaghobi; Fatemeh Bena Kashani
Volume 9, Issue 2 , January 2012
Abstract
The probability of Barnyardgrass resistance to some common rice herbicides used in the rice fields of Gilan, Mazandaran and Fars Provinces was investigated by conducting a series of greenhouse and Petri dish bioassay tests on 37 biotypes collected in 2005-2006. Greenhouse experiments involved screening ...
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The probability of Barnyardgrass resistance to some common rice herbicides used in the rice fields of Gilan, Mazandaran and Fars Provinces was investigated by conducting a series of greenhouse and Petri dish bioassay tests on 37 biotypes collected in 2005-2006. Greenhouse experiments involved screening tests with Petri dish tests implementing dose response assays to determine doses of herbicides inhibiting root and stem length growth by 50% (ID50) as well as to determine the sensitivity of the biotype to herbicides. Screening tests were carried out for each province separately for a given herbicide using a randomized complete blocks design with four replications. Minimum recommended doses of Butachlor, Molinate, and Thiobencarb were added to pots of 8cm water height before 2-leaf growth stage of Barnyard grass. Propanil was sprayed at the 3-4 leaf stage. Measurement of dry weight, number of surviving plants and visual rating (based on the EWRC rating scale) were conducted 4 weeks after treatments. A completely randomized design with four replications was also used in the Petri dish tests. This sensitive biotype was subjected to a range of herbicide doses resulting in 50% inhibition of root and stem growth and the response of biotypes to the ID50 of the sensitive biotype was further studied. Root (for Propanil) and stem length (for Butachlor, Molinate, and Thiobencarb) were measured 7 days after treatments. According to results obtained from greenhouse and Petri dish assays, it was revealed that Barnyardgrass biotypes collected from Gilan, Mazandaran and Fars Provinces were not resistant to the tested herbicides (Propanil, Butachlor, Molinate, and Thiobencarb). The results from Petri dish tests were correlated to those of greenhouse experiments.
Hassan Esmaeilzadeh; Mozaffar Sarrafi; Jamileh Tavakkoli Nia
Volume 9, Issue 2 , January 2012
Abstract
In the third millennium, undoubtedly tourism has been upgraded to one of the thriving bases of the global economy and, on the base of findings, it can be identified as the main economic resource for many countries. Tourism, along with its many benefits, has many negative effects as well; coping with ...
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In the third millennium, undoubtedly tourism has been upgraded to one of the thriving bases of the global economy and, on the base of findings, it can be identified as the main economic resource for many countries. Tourism, along with its many benefits, has many negative effects as well; coping with these requires us to rely on a suitable approach and proactive measures by planners and mangers, especially in the public sector. In this article we have attempted to study tourism development approaches, selecting the most suitable approach in relation to local community development. The spectrum of approaches includes the boosterism, economic (industry-oriented), spatial-geographical, community-oriented, and sustainable approaches, all of which have been described and compared, using SWOT analysis. Finally, the most appropriate approach in terms of the development of community-centered tourism has been elaborated.
Mohammad Hossein Rajabi,; Afshin Soltani,; Bita Vhidnia,; Ebrahim Zeinali; Elias Soltani
Volume 9, Issue 2 , January 2012
Abstract
With regard to the careless consumption of fossil fuels in Iran and the resulting greenhouse gas emissions and related risks to the environment and human health, many attempts are being undertaken to try to control this consumption. The agricultural sector is no exception to this vital and important ...
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With regard to the careless consumption of fossil fuels in Iran and the resulting greenhouse gas emissions and related risks to the environment and human health, many attempts are being undertaken to try to control this consumption. The agricultural sector is no exception to this vital and important issue. The objectives of this research were: (1) to determine amount of fuel consumption and related energy use in wheat fields in Gorgan Province, (2) to estimate the environmental impact of the consumed fuel using global warming potential (GWP), and (3) to explore options to optimize fuel consumption. Data were gathered from six representative fields by monitoring production practices and inputs used. Data were analyzed with regard to fuel consumption, energy inputs related to fuel consumed and greenhouse gas emissions from the consumed fossil fuels. Fuel ranged between 53 to 123 L ha-1 and the energy from the consumed fuel varied between 2026 to 4664 MJ ha-1. Results indicated that seedbed preparation had the highest rate of fuel consumption (59.5 % of total) followed by harvesting, irrigation and sowing operations at 10.5, 9.4 and 8.1 %, respectively. The average of greenhouse gas emissions (CO2, CH4 and N2O) from the consumed fossil fuels was estimated at 244 kg equivalent CO2 ha-1. It was concluded that through better farm management and more research it is possible to reduce fuel consumption and greenhouse gas emissions.
Masoud Yazdanpanah; Dariush Hayati; Gholam Hossein Zamani
Volume 9, Issue 1 , October 2011
Abstract
Despite the increasing importance of water conservation across the world, there is very little understanding about the psychosocial variables that help predict people’s water conservational behaviour. This study used a modified model of the Theory of Planned Behaviour (TPB), including the additional ...
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Despite the increasing importance of water conservation across the world, there is very little understanding about the psychosocial variables that help predict people’s water conservational behaviour. This study used a modified model of the Theory of Planned Behaviour (TPB), including the additional variables of moral norms, self-identity and subjective myths of the nature as general beliefs, to predict intentions and behaviour regarding water conservation through a random sample of agricultural professionals (n= 80) using the survey method in Bushehr Province. Findings revealed that the modified theory of TPB can explain intention and behaviour regarding water conservation. Multiple regression analysis showed that moral norms, perceived behavioural control and risk perception can predict 68 percent of variances in water conservational intention, while subjective norms and perceived behavioural control can predict 49 percent of variances in water conservational intention based on the original TPB model. Therefore, those agricultural professionals who perceived a greater normative and commitment feeling regarding water conservational behaviour had a higher level of intention to engage in such behaviours and the significance of perceived behaviour control revealed that professionals did not have complete volition in their water conservational behaviour. Furthermore, myths of nature can predict about 39 percent, 20 percent and 28 percent of variances in attitude, moral norms and risk perception regarding water conservation.
Mehdi Nooripoor; Mansour Shahvali
Volume 9, Issue 1 , October 2011
Abstract
"Information", "persuasion", "dialogue" and "consensus building" were taken as the possible communication strategies to facilitate Sustainable Animal Husbandry (SAH) in rural areas of Kohgilooyeh County, Southwestern Iran. Also, various different aspects of SAH attributes were considered which include ...
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"Information", "persuasion", "dialogue" and "consensus building" were taken as the possible communication strategies to facilitate Sustainable Animal Husbandry (SAH) in rural areas of Kohgilooyeh County, Southwestern Iran. Also, various different aspects of SAH attributes were considered which include organizational sustainability, sustainable programs, use of proper media, focusing on target customers, and suitable monitoring- evaluation systems. The study was carried out using Evidential Reasoning, aMultiple Attribute Decision Making (MADM) technique, to choose the most appropriate communication strategy for SAH in the study area. Results indicated that, generally, "dialogue" was the first communication strategy that should be chosen for SAH. Of course, it was revealed that communication strategies would vary depending on the attributes of sustainability. More detailed results, especially about how to choose media based on the communication strategy, are presented in the body of the paper.
Afshin Honarbakhsh; Seyed Javad Sadatinejad; Moslem Heydari; Mohamadreza Mozdianfard
Volume 9, Issue 1 , October 2011
Abstract
Lag time is a parameter that appears often in theoretical and conceptual models associated with river basin. The river basin lag time is an important factor in linear modeling of river basin response. Generally, all hydrologic analyses require at least one of the time parameters of river basin and, in ...
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Lag time is a parameter that appears often in theoretical and conceptual models associated with river basin. The river basin lag time is an important factor in linear modeling of river basin response. Generally, all hydrologic analyses require at least one of the time parameters of river basin and, in the majority of cases, time of concentration or lag time are used. In this research, storm data from 6 stations in the North Karoon river basin (in Iran) were analyzed. From this analysis, 23 events were selected. Then, in one experimental sub-basin located in this river basin, the lag time was calculated using field method. In this method, performed in the Darehbeed-Samsami study area, lag time was computed from a hydrograph generated by discharge measurement of a triangular scaled spillway. After that, 23 events were divided into two groups, including, one for a newly developed empirical model (70 percent) and another for validation of this model (30 percent). The results obtained from this research based on coefficient of determination (R2), root mean square error (RMSE) and relative error (%RE) statistical measures showed that the agreement between the computed(from new empirical model) and measured data is good.
Jamileh Pazooki; Faezeh Ghaffar Haddadi; Behrooz Abtahi
Volume 9, Issue 1 , October 2011
Abstract
Metal concentrations in commercial and non-commercial fish were surveyed to assess risks of fish consumption to human health and importantly, assess contamination in the food chain. In this study, lead (Pb), Zinc (Zn) and Copper (Cu) concentrations were determined in muscle and skin tissues of wild and ...
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Metal concentrations in commercial and non-commercial fish were surveyed to assess risks of fish consumption to human health and importantly, assess contamination in the food chain. In this study, lead (Pb), Zinc (Zn) and Copper (Cu) concentrations were determined in muscle and skin tissues of wild and cultured Cyprinus carpio (common carp) from the southeastern Caspian Sea area and a nearby fish farm in November 2007. Metal concentrations were determined by atomic absorption. Pb and Cu concentrations in all of the samples were below detection limits and there were no statistically significant differences of Zn concentrations in muscle and skin tissue between wild and cultured carp. But Zn concentrations in the skin tissue were significantly higher than in muscle tissue in both groups; this suggests that more studies about skin tissue as a site of bioaccumulation are necessary. None of the concentrations exceeded WHO safety standards. Our results have suggested that heavy metal contents in carp are negligible and that its consumption should pose no health problems for consumers of either the wild or farmed fish.
Ali Akbar Noroozi,; Mehdi Homaee; Abbas Farshad
Volume 9, Issue 1 , October 2011
Abstract
Soil salinity expansion is an environmental challenge particularly in arid and semi arid regions. In order to evaluate the progressing extent of soil salinity in relation with natural and human-induced conditions, a study was conducted using the Landsat TM imagery. The present study was conducted in ...
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Soil salinity expansion is an environmental challenge particularly in arid and semi arid regions. In order to evaluate the progressing extent of soil salinity in relation with natural and human-induced conditions, a study was conducted using the Landsat TM imagery. The present study was conducted in the Garmsar area to the East of Tehran. A total of 288 soil samples were analyzed to determine the relationship between the spectral reflectance and Electrical Conductivity (EC), as salinity indicator. Multiple regression analysis and Ordinary Least Square regression (OLS) were used to examine the relationships between EC and derived spectral to generate several models. In the case of derived spectral, mid-infrared band (TM Band-7), visible band (Band-1), Tasseled cap3 (Wetness index) and PCA2 (Principal Component Analysis) were found to be most correlated with the observed EC values of the surface layer of the soil, at 99% confidence level. The accuracy of the prediction model was tested using a validation set of 52 soil samples in Eyvanekey plain, close to study area where the environmental circumstance consist of similar properties. RMSE and MAE were used to evaluate the performance of the map prediction quality. Results showed that the appropriate model could predict the soil salinity with precision of 4.1 and 0.49 dS m-1, respectively. The predicted salinity ranged from 0dS/m to 110dS/m. Therefore, the EC estimations were suitable to generate soil salinity map. Sensitivity analysis was tested on applied parameters that showed Band-1 and Band-7 were 3 and 2 times more than sensitive rather than other parameters respectively. The results are promising and certainly useful for soil salinity prediction.
Mohammad Mahdi Hosseinzadeh; Ahmad Nohegar
Volume 9, Issue 1 , October 2011
Abstract
Extraction of water from underground sources is on the increase, especially from basins stored by non-strengthened alluvium, sediments and from shallow areas of the sea. This results in sinking on the surface and leads to ground subsidence. In recent years, the Minab Plain, like many areas of Iran has ...
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Extraction of water from underground sources is on the increase, especially from basins stored by non-strengthened alluvium, sediments and from shallow areas of the sea. This results in sinking on the surface and leads to ground subsidence. In recent years, the Minab Plain, like many areas of Iran has faced drought, which has led to more uptake of subterranean water; this lowers the underground water level and results in sinking which appears on the surface as a sinkhole following subsidence. A field study of this sinking phenomenon involves the following procedure: Firstly, the analysis of the drought occurrences in the area including features of water table, sediment and bedrock. Secondly, the consideration of exploitation of the subsurface water; and finally, identification of the different forms of subsidence in the area from the information acquired above. Statistics from the Sheikh Abad rain-gauge station (covering a period of 27 years) were used for this investigation. Data on precipitation are presented with the decimal method and the standard precipitation index, an index that shows any decrease of climatic rainfall in the area. This data shows that in recent decades there has been less than normal rainfall and that the area has undergone a period of intense drought. In most parts of the plain new alluvium was formed at a depth of 2-3 meters from the surface, the sediment of which often constitutes large grains, which gradually changed to form finer sediment in the form of sand, silt and clay containing salt-water. Therefore, it can be said that with increasing depth, the sediments become tinier (smaller) with an increase in salinity. All of the wells in this area have settled on washed silt sediment and have a high density around the rivers of the Minab area. Because of recent droughts and the drying up of the water supply canals of Minab dam, the digging of wells has increased from 164 in 2002 to a current figure of 607 dug wells. Critical factors related to occurrences of subsidence, are that the existing alluvium covering with the varying thickness up to 150 meters has formed small-grain, silt clay-silt loam soil, which has increased surface subsidence following extraction of underground water over the past two decades.
Mohammad Ghofrani; Sakineh Pishan,; Mohammad Reza Mohammadi,; Hossein Omidi
Volume 9, Issue 1 , October 2011
Abstract
This study was undertaken to determine the possibility of using lignocellulosic material as reinforcing filler in wood plastic composite (WPC). Recycled high density polyethylene was used as the matrix and rice-husk flour as the reinforcing filler to prepare a wood-plastic composite. WPC specimens of ...
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This study was undertaken to determine the possibility of using lignocellulosic material as reinforcing filler in wood plastic composite (WPC). Recycled high density polyethylene was used as the matrix and rice-husk flour as the reinforcing filler to prepare a wood-plastic composite. WPC specimens of 45×25×1.6 cm were manufactured using a hot press (T: 200°C, P: 160 bar and t: 7 min). In the sample preparation, high density polyethylene (HDPE) was added at two loadings (40%, 60%) and WPC densities of 0.7 and 0.8 g/cm3 were tested. In order to examine the compatibility of rice husk with the polymer, maleic anhydride grafted polyethylene (MAPE) was used as a coupling agent and was a variable factor (0%, 3% and 6%). Twelve treatment groups were considered with 3 replicates per treatment, so a total of 36 groups were tested. Water absorption and the thickness of the swelling were measured after 2 and 24 hours. The mechanical properties of the specimens were determined, namely the bending strength, modulus of elasticity and internal bonding strength. According to the results, the optimum treatment with the best physical and mechanical properties was WPC at 0.8 g/cm3 density, 60% HDPE and 6% coupling agent. Results showed that with an increased content of coupling agent (MAPE), the physical and mechanical properties improved. Having significant differences between the data for water absorption and the thickness of the swelling, the optimum treatment also showed acceptable levels.
Nasser Ali Azimi; Sajjad Barkhordari
Volume 9, Issue 1 , October 2011
Abstract
The analysis of income effect on environmental quality has been an important debate in the 1990. Several papers have used different approaches for an analysis of the relationship between income and environmental quality. Also, many of these papers have employed different measures of pollutants and income. ...
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The analysis of income effect on environmental quality has been an important debate in the 1990. Several papers have used different approaches for an analysis of the relationship between income and environmental quality. Also, many of these papers have employed different measures of pollutants and income. The U inverse relationship between income and the level of pollution has been confirmed in many papers. In this paper, the relationship between pollution and income has been extracted by means of their microeconomic foundations. The U inverse relationship between the pollution generation (CO2) and GDP per unit of energy use has been tested for selected OECD and OPEC countries in 1980-2003 and 1985-2003. The results of this paper show that the economic structure of the group of countries selected and the period of time had a major role to play in rejection or acceptance of the Environmental Kuznet’s Curve hypothesis. Also, the elasticity of the problem of pollution and GDP per unit of energy use for selected OPEC countries is almost two times that of the OECD countries.
Seyed Majid Zabihzadeh; Mohammad Tagh i Asadollahzade; Maryam Ahmadi; Hossein Kermanian
Volume 8, Issue 4 , July 2011
Abstract
The objective of this study is to develop a new process for the production of pulp using the wheat straw. Environmentally-friendlywheat straw pulp with potassium hydroxide was prepared, and their mechanical and optical properties were studied. Pulping tests were carried out varying active alkali (16, ...
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The objective of this study is to develop a new process for the production of pulp using the wheat straw. Environmentally-friendlywheat straw pulp with potassium hydroxide was prepared, and their mechanical and optical properties were studied. Pulping tests were carried out varying active alkali (16, 18 and 20 wt %) and cooking time (60 and 90 min). Liquor-to-solid ratio, time to reach the maximum temperature and the cooking temperature were kept constant. The increase in active alkali significantly reduced the yield and kappa number of the pulp. Chemical pulps of 48.71–53.73% yield produced from the KOH pulping process exhibited acceptable papermaking properties comparable to those of soda pulp. Refining the pulps increased the tensile index, breaking length, and burst index of the handsheets. The tear index and brightness were lower for refined pulp compared with the unrefined one. The black liquor of this process can be utilized as a fertilizer for agricultural production.
Safdar Hosseini,; Mohammad Ghorbani; Mohammad Torshizi
Volume 8, Issue 4 , July 2011
Abstract
The present study was undertaken with a view to choosing a macroeconomic policy for preventing soil erosion in Iran. In choosing the appropriate policy, this study not only calculated the environmental impacts of various policies, but also it analyzed their impacts on some important economic indices ...
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The present study was undertaken with a view to choosing a macroeconomic policy for preventing soil erosion in Iran. In choosing the appropriate policy, this study not only calculated the environmental impacts of various policies, but also it analyzed their impacts on some important economic indices such as total real production, in a General Equilibrium framework. Results show that both the economic and environmental impacts of an Upland Food Production Tax are very favorable in comparison with a Lowland Food Production Subsidy. Finally, as a policy recommendation, it is suggested that regardless of any practical problems associated with either of the policies, the Upland Food Production Tax is potentially the appropriate policy to overcome the soil erosion of upland areas which are under cultivation by rain-fed crops.
Nadia Sharifzadeh; Bita Ayati; Hossein Ganjidoust
Volume 8, Issue 4 , July 2011
Abstract
Companies need to design engineering software to obtain emission limits before construction and commissioning the plants to control air pollutants. During the design of plants, all emissions should be studied and measured. Since some emissions are lighter or higher than air, there are different methods ...
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Companies need to design engineering software to obtain emission limits before construction and commissioning the plants to control air pollutants. During the design of plants, all emissions should be studied and measured. Since some emissions are lighter or higher than air, there are different methods for their modeling. These models are used for reviewing the effect of gases on the environment and the best model is the one that can design an accident before dispersion. In this research three software packages, namely PHAST, CIRRUS and SHELL FRED, were compared with a newly-created software for measuring the ground level concentration of H2S and SO2. The software packages were based on the Gaussian model for point sources. In these models, for simplicity, some assumptions were made based on one point source above the ground. According to the results, the new software was similar to CIRRUS in D stability of the air that can be used instead.
