جستجوی مقالات مرتبط با کلیدواژه "iran" در نشریات گروه "منابع طبیعی"

The rural areas of Iran are known as the most important hubs for the production of agricultural products. Considering that income distribution has an effect on the level of poverty and economic well-being of rural people, knowing the factors affecting how income is distributed in the rural areas of the country will be necessary to develop poverty alleviation policies. Identifying these factors will pave the way for appropriate measures in the first place to improve the pattern of rural income distribution and in the second place to reduce rural poverty in Iran. The purpose of this research is to investigate the effect of trade liberalization and the quality of human resources on the Gini coefficient in rural areas of Iran for the period of 1971-2020. For this analysis, Vector Autoregressive Model, Johansson-Juselius method Engel-Granger method and Vector Error Correction Model are used. The findings of the research based on The coefficient of the error correction method indicates that about 0.61 of the short-term imbalance is adjusted in each period to achieve the long-term equilibrium, and it can be said that in the long-term, a one percent increase in the variables. The quality of human resources (literacy rate of farmers) and the relative income of agriculture causes a decrease of 2.78 and 2.03 percent in the inequality of income distribution, respectively, and a one percent increase in the economic growth variables of the agricultural sector, the government's construction expenditures for agriculture, the index The degree of commercial openness and the ratio of agricultural investment cause an increase of 68%, 0.51%, 2.85% and 1.18% respectively in the inequality of income distribution, and among the types of variables mentioned, the effect of the index of the degree of commercial openness on the inequality of distribution income is more compared to other variables.

Life expectancy shows having a better and more appropriate standard of living. As a result, Awareness of the above index in rural areas helps government officials and rural planners in decision making. The aim of this secondary data analysis research was to estimate and zoning of life expectancy in rural areas of Iran in 2016. In the research method, based on the official secondary data of the country, the life expectancy table was created and life expectancy were calculated for the rural areas of the provinces of the country, then these areas were zoned using Arc GIS. Based on the results, Tehran province in terms of villagers’ life expectancy has the best location among all of provinces. The amount of this index in Tehran province was different from 74.60 for all of rural people to 74.71 for rural women and 74.50 years for rural men. The worst situation of villagers’ life expectancy in Iran was related to Sistan and Blochestan province, because, the amount of this index was for all villagers’ people 67.26 and for women 67.76 and finally for men 66.76 years. The highest life expectancy between all groups and provinces, related to Tehran province rural women’s with 74.71 years and the lowest was related to the rural men of Sistan and Baluchestan with 66.76 years. Women had more life expectancy than men in all provinces. Finally, the rural people of different provinces placed in three areas of good, moderate and weak in terms of life expectancy index. Planners and policymakers can take over the elimination of deficiencies and deficits in weak areas and improve life expectancy in other areas of the appropriate actions.

 Agricultural sector has a considerable and increasing share from total energy consumption of societies. The growth in population and living standards increase the demands for agricultural products. The limitations in cultivatable land area forces the need for increase in yield per area unit. It emphasis on the importance of energy and resources analysis in agriculture. Several researches in the world have been conducted around the energy consumption in agricultural farms, as well in Iran. However, there is a need for comprehensive studies analyzing the results of these researches. The aim of this study was the analysis of the consumed and produced energy for one of maize corn in Iran. The energy indices, obtained from related published studies were analyzed. The energy indices were determined as the energy output-input ratio (OIR), energy productivity (EP), energy intensity (EI) and net energy yield (NEY). The results indicated that, the average yield of maize corn in different provinces of Iran is around 6167 kg ha-1, requires an average energy input of 55 GJ ha-1. The largest share from total energy input was related to nitrogen fertilizer 29%, followed by electricity and diesel fuel with 28% and 16%, respectively. The average OIR was 2.92 MJ/MJ where the highest and lowest values were for Fars (5.8) and Khuzestan (0.8) provinces. The average EI was 9.47 MJ/kg, where it was the highest with 21.02 MJ/kg for Alborz and the lowest with 4.61 MJ/kg for Gholston.

Agricultural sector has a considerable and increasing share from total energy consumption of societies. The growth in population and living standards increase the demands for agricultural products. The limitations in cultivatable land area forces the need for increase in yield per area unit. It emphasis on the importance of energy and resources analysis in agriculture. Several researches in the world have been conducted around the energy consumption in agricultural farms, as well in Iran. However, there is a need for comprehensive studies analyzing the results of these researches. The aim of this study was the analysis of the consumed and produced energy for one of maize corn in Iran. The energy indices, obtained from related published studies were analyzed. The energy indices were determined as the energy output-input ratio (OIR), energy productivity (EP), energy intensity (EI) and net energy yield (NEY). The results indicated that, the average yield of maize corn in different provinces of Iran is around 6167 kg ha-1, requires an average energy input of 55 GJ ha-1. The largest share from total energy input was related to nitrogen fertilizer 29%, followed by electricity and diesel fuel with 28% and 16%, respectively. The average OIR was 2.92 MJ/MJ where the highest and lowest values were for Fars (5.8) and Khuzestan (0.8) provinces. The average EI was 9.47 MJ/kg, where it was the highest with 21.02 MJ/kg for Alborz and the lowest with 4.61 MJ/kg for Gholston.

In achieving sustainable livelihoods in rural areas, the need for accurate and complete identification of factors affecting the process of formation and development of rural areas is necessary. In this regard, identification and evaluation of criteria and indicators of sustainable rural livelihoods can be promising. In this study, it has been tried to identify and evaluate the criteria and indicators of rural sustainable livelihood in the country through a comprehensive review of the library resources and existing records. For this purpose, factors influencing rural sustainable livelihood were formulated in the form of a group of criteria, and indicators for each criterion. In the next step by using the Delphi method and using normalized importance coefficient, the indices were screened. Based on the results, the economic criterion group with the highest Normalized Importance coefficient (0.338) was identified as the most important criterion group. Two income and cost and water resources criteria with normalized importance coefficient 0.720 and 0.070 are more important than the other criteria, and then the employment and health of the society criteria are at the next levels. Among the indicators of sustainable livelihoods, household income index is ranked first with the normalized importance coefficient 0.0084. And two indicators of assets and household expenses are ranked second with the same importance coefficient (0.0081).

Agricultural sector has a considerable and increasing ratio of the total energy consumption of the societies. The main causes of the increase in energy consumption in this sector are: the growing population and living standards and therefore, increasing demands for agricultural products, the limitations of cultivatable land area and thus, the need for increase in the yield per area unit, and the low price of fuels and other energetic inputs, especially in Iran. This subject represents the importance of the energy and resources analysis in agriculture. Several researches have been done about the energy consumption in agricultural fields in the world and also different regions of Iran. However, there is a need for a comprehensive study on the obtained results of these researches. In this study, the consumed and produced energy for one of the main crop of Iran (wheat) through the energy indices, obtained from related papers and dissertations, were analyzed. The energy indices were determined as the energy output-input ratio (OIR), energy productivity (EP), energy intensity (EI) and net energy yield (NEY). The results indicated that, the average total energy consumption for wheat production was 34800 MJ/ha in Iran. The mean grain yield was about 4230 kg/ha for normal conditions on irrigated farms. The largest share of energy input was related to nitrogen fertilizer followed by diesel fuel and machinery, responsible for 32, 22 and 15% of the total energy input, respectively. The average OIR was 2.09 MJ/MJ for Iran with the highest and lowest values for provinces of Goldstein (3.72) and Sistan (0.81). The average EI was 8.23 MJ/kg, for Sistan and Baluchestan province being the highest with 17.8 MJ/kg and for Golestan province being the lowest with 3.9 MJ/kg.

The grass carp (Ctenopharyngodon idella) is mainly used for the food production and aquatic weeds control. The aim of this study was to assess the feeding preference of grass carp by 3 submerged plants including curly pondweed (Potamogeton crispus), Eurasian watermilfoil (Myriophyllum spicatum) and coontail (Ceratophyllum demersum), 2 free floating plants including water fern (Azolla filiculoides) and duck weed (Lemna minor) and water silk (Spirogyra sp.). The research was carried out at the Shahid Ansari Fish Reproduction and Breeding Center in 2011. Vegetative organs of experimental plants were collected from the Anzali lagoon and planted in the fish aquaculture. Four weeks later (on 5, May 2011), the grass carp by average weight of 20 g were released in the pools and monthly weighted by the end of experiment. The results showed significant (p<0.001) increase of grass carp weight in the eurasian watermilfoil, duck weed and water silk submerged plants treatments compared to the other treatments. The maximum weight and length of grass carp were observed in duck weed (380 g, 31 cm), eurasian watermilfoil (365 g, 29 cm) and water silk (350 g, 28 cm). The maximum fat percent were also measured on eurasian watermilfoil, water silk and duck weed with 7.21, 7.15 and 7.08%, respectively. Besides the maximum protein content were measured in eurasian watermilfoil, water silk and duck weed treatments with 16.02, 15.88 and 15.68%, respectively

The Studied region located in NW of Yazd in Yazd province. The lowest and highest altitudes of the area are 1530 and 3260 m, respectively. Average annual precipitation in ten years period (1998-2007) reaches to 98 mm that lowest and highest are 32 and 205 mm, respectively. Flora of this area includes 255 plant species that belong to 168 genera and 44 families. The important families are include : Asteraceae with 41 species (16%), Papilionaceae and Brassicaceae with 26 species, Poaceace with 22 species, Lamiaceae with 21 species ,Chenopodiaceae with 20 species, Apiaceae and Caryophyllaceae with 10 species , Boraginaceae with 9 species and Eupphorbiaceae with 6 species, respectively. Life forms of the plant species of the area include: Hemicryptophytes 94 species (381%), Therophytes 24%, Chamaephytes 18%, Phanerophytes 10% and Geophyte 10%. From the view point of chorology plants of this region include: 68.6% Irano-Turanian, 14.1% Irano- Turanian and Saharo-Sindian, 5.9% Irano- Turanian and Mediterranean, 3.9% Irano-Touranian and Mediterranean and Saharo- Sindian 3.1% cosmopolitan , 2.4% Irano- Turanian and Euro- Siberian , 1.2% Irano-Touranian and Mediterranean and Euro-Siberian and 0.8% Irano-Turanian and Euro-Siberian and Saharo-Sindian determined. From the 255 species of flora in this area, 44 species are endemic in Iran and two of these species include: Helichrysum davisianum and Hymenocrater yazdianus are endemic in Yazd.

Corrugated board is considered a valuable commodity for packaging at both international and domestic markets. therefore it is necessary to identify the consumption and production patterns as well as the most important and effective variables on it for the development of corrugated board production industry in Iran and understanding the variation in demand for this product, Based on this information it can be forecasted. In this study, the dynamic econometric model has been used to demonstrate simultaneous relationship between supply and demand. Coefficients of the model were estimated applying 3SLS procedure with the time series data from 1981 to 2007. In this respect before estimating equations Augmented Dicky-Fuller (ADF) test was used for the analysis of the variables cointegration at 5% significant level.The study results indicated that in the demand function, the variables including, intercept, price,GNP in the previous period, Population, CPI, industrial added value IAV and the war dummy are significantly different at 0.05% level. However, in the supply function, intercept, production ,consumption and import quantity in the previous period, inflation rate, cost price in the previous period simultaneously influence consumption and production.

the mixed Fagus orientalis site is located in range of altitudinal girdle in central Alborz forest was investigated. According to plant sociology and ordination methods vegetation and physical and chemical characteristics of soil were analyzed. Sam pling of plant com panent were took from 26 releves with(400m2) area. The soil data analyzed in lib. By using of different method of ordination such as DCA and CCA were improved environmental gradient. The results of phytosociology with Bran-Blanquet combined scale were determined 2 communities,2 sub-communities and1variant in this site. The Carpino-fagetum community is greatly expanding in Mazandaran forest and central Alborz, but Vaccine-fagetum was reported in Mazandaran for the first time. The environmental factors such as N, Mg and Na were effective in division plant communities.