Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
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.
Original Articles
Gholamali Sharzei; Mohsen Mohaghegh
Volume 9, Issue 2 , January 2012
