Showing 43 results for Arm
Mansour Zibaei, Gholam Reza Soltani, Ahmad Ali Keykha,
Volume 2, Issue 4 (1-1999)
Abstract
The production and acreage of corn in Iran and in Fars Province, in particular, are expanding at an increasing rate. The impacts of this event was studied by a risk programming model (MOTAD). The results indicated that the optimal cropping patterns with corn had less variance than the optimal patterns without corn in all income levels. The results also showed that with the introduction of corn into cropping pattern, the use of land and water were increased, but the rate of increase in the use of land was more than the rate of increase in the use of water. By determining risk - aversion coefficient for the sample farmers, their sensitivity to corn price changes were studied. The results indicated that the relationship between corn and wheat is complementary but it is competing with barley, sugarbeet, cotton, cucurbits and legumes.
Daryoosh Hayati, Ezzatollah Karami,
Volume 3, Issue 2 (7-1999)
Abstract
Studies on sustainable agricultural have not paid adequate attention to farmers' behaviour regarding sustainability. The objectives of this research were: 1) to determine the relationship between socio-economic and farming factors with “sustainable agricultural knowledge”, 2) to predict “sustainable agricultural knowledge” based on socio-economic and farming factors, and 3) to determine the relationship between sustainable agricultural knowledge and sustainability of farming systems. A survey research was used with a multi-stage cluster sampling technique to collect data for the study. In the first stage, 39 villages were selected in Fars Province. Then 200 wheat producers were randomly selected in these villages for interview. The findings indicated that there was a significant and positive correlation between “sustainable agricultural knowledge” with level of literacy, achievement motivation, amount of total wheat production, technical knowledge about wheat production, economic condition, wheat farming model, amount of supervision by Agricultural Service Centers, and educational services provided by extension agents. Stepwise multiple regression indicated that technical knowledge about wheat production, achievement motivation, type of land revenue system, level of literacy and wheat farming model (independent variables) explained more than 50 percent of variability in “sustainable agricultural knowledge”. There was no significant correlation between “sustainable agricultural knowledge” and “sustainability of farming systems”. Possible reasons for this lack of relationship have been discussed. Based on the findings of this study, recommendations are provided towards achieving a more sustainable agricultural system.
M.r. Mosaddeghi, M.a. Hajabbasi, A. Hemmat, M. Afyuni,
Volume 3, Issue 4 (1-2000)
Abstract
Soil structure maintenance and stability is an important index indicating sustainable soil management. In this regard, components such as soil moisture and organic matter affect soil compactibility during farm machinery trafficking. Soils in Central Iran are commonly very low in organic matter (OM) and thus susceptible to compaction. This study was conducted to measure the effects of soil moisture content and manure application on soil compactibility. A randomized complete block design with four blocks (replicates) with the treatments nested (split-block) into the blocks was used in the soil (Typic Haplargids), located in Isfahan University of Technology Research Farm (Lavark). One-year aged manure treatments 0, 50, and 100 t ha-1 were incorporated into soil up to the tillage depth (20 cm) by a heavy disc. After five months (July-November), a two-wheel-drive tractor Universal Model U-650 was passed through the field at soil moisture contents of plastic limit (PL), 80% PL (0.8PL), and 60% PL (0.6L), either once (P1) or twice (P2). Bulk density (BD), cone index (CI), and soil sinkage (S) were measured as indices of soil compactibility and trafficability. Adding manure countered the effects of load and wetness on BD and CI, significantly. There was a significant difference between the effects of 50 and 100 t ha-1 of manure on BD but not on CI. Manure application reduced soil sinkage at high moisture contents (PL) but increased it at low moisture contents (0.6PL). Adding manure also reduced the BD and CI of subsoil. Repeating the passage of tractor (P2) increased compaction significantly. The significant increase in BD and CI did no occur at 0.6PL. When no manure was applied even at 0.6PL, there were limitations for trafficability, whereas this limit for 50 t ha-1 treatment was reached at 0.8PL. Results from this study indicate that the manure application at a rate of 50 t ha-1 reduces soil compactibility and increases soil moisture trafficability range.
S.j. Khajeddin,
Volume 4, Issue 4 (1-2001)
Abstract
Astracantha adscendens is an endemic species in Iran growing on alpine and above alpine timberline habitats on the Zagross Mountain Range. These habitats are characterized by steep slopes, heavy snowfalls and long ice formation periods. The present study was carried out in Chelgerd, Bakhtiari, and Fereidan, Isfahan. Slopes, elevation above sea-level, and magnetic north azimuth were measured. The canopy cover was also measured along four radii in upward, downward, left and right directions. Regression analysis was performed for the measured values of plant and environmental factors.
The results revealed that the upward radius had a high negative correlation with slope changes while the downward radius showed no relationship with slope variations. The two left and right radii had a high and positive relationship with each other, both reducing in length as the slope steepness increased. Shrub volume decreases with increasing slope steepness. Plant shape was classified into seven groups using Sorenson similarity index and constructing the dendrogram. Snow pressure bends the stem toward the soil surface. Snow gliding pressure scratches stem and its base buds above the bent stem. Soil and debris move downward the slope as a result of snow gliding and rainfall runoff as well as wildlife and domestic animals. Snow gliding along with other natural factors have various effects on A. adscendens plant form which can be grouped under three categories: direct mechanical effect of snow, physiological effect of snow, and indirect effect of precipitation and wildlife. The environmental factors and plant physiological responses to them change the A. adscendens plant form from a funnel or ob-conical shape to a semi-funnel or semi ob-conical form.
S.m. Nassiri, M. Loghavi, J. Jafarifar,
Volume 5, Issue 2 (7-2001)
Abstract
Wheat as a main food source is partly lost in different ways such as planting, harvesting, storage and even in consumption processes. This calls for attention to reducing these losses through application of the results from agricultural research, use of new farming practices, improvements in management system and repair and renewal of farm machinery. The present study considers the design, development and evaluation of a new pneumatic air reel system as a replacement for the conventional mechanical reel. To evaluate the new system, laboratory and field tests were conducted.
In the laboratory tests, the air velocity was measured along the fan outlet width at a 10 centimeter interval from the outlet to 40 centimeters away from it, and corresponding curves of air velocity distribution along the fan outlet width were drawn. On the basis of the results, 13 fans were calculated to be required on the cutting platform of a 14-foot (4.3 meter) combine. The results from the field tests of mechanical and air reels show that grain losses of air reel during harvesting are less than those of the mechanical reel because the air reel has no mechanical contact with the crop and applies less shock on plant stem than the mechanical reel. According to the results, grain losses increased linearly with increasing fan speed. In addition to the change of fan speed (2247, 2503, 2860, 3218 and 3932 RPM), three air discharge directions of 10, 20 and 30 degrees from horizontal line were examined. According to the data analysis in Randomized Complete Block Design (RCBD) through Tukey’s procedure (15 treatments and 6 samples in each treatment), there were significant differences between grain loss at these directions and mechanical reel at a level of 5%. A wind direction of 20 degrees and fan speeds of 2503 to 2860 RPM are recommended.
M. Abdollahi Ezzatabadi, G.r. Soltani, A. Nejati,
Volume 5, Issue 4 (1-2002)
Abstract
In this paper, a simple farm management information system is introduced. This system was administered through cooperation between farmers and an information agency. The results showed that the farmers were willing enough to accept the system. Nevertheless, having an accounting system is the first step toward the establishment of an information system, which is used by only %42 of the sampled farmers. The main reason for this is the lack of knowledge about the benefits of such systems. In other words, if farmers were aware of the benefits of accounting systems, they would accept them easily. The results also showed that the farmers who use accounting systems are more successful in their production activities.
A. Ahmadi Iikhchi, M. A. Hajabbassi, A. Jalalian,
Volume 6, Issue 4 (1-2003)
Abstract
Cultivating rangeland to be shifted to crop land farms commonly causes soil degradation and runoff generation. This study was conducted to evaluate the cultivation effects on runoff generation and soil quality. The experiment was performed in a rangeland and a 40-year cultivated land located at two slope positions (back slope and shoulder) of a hillside in Dorahan, Chaharmahal & Bakhtiari Province. A 60±5 mm.hr-1 rainfall intensity was simulated by a rainulator. Organic matter, mean weighted diameter, saturated hydraulic conductivity, collected runoff and sediments were measured. The differences between the means were tested using T-test. Results showed 35, 53 and 8% increases in the organic matter, mean weighted diameter, and saturated hydraulic conductivity in back slope, respectively. The increases in these parameters in shoulder position were 39, 60 and 33%. The values for runoff and sediments in back slope were 3 and 8 times greater than in other similar positions while the values in the shoulder position were 11 and 55 times greater than the same values in other positions.
M. J. Nazemosadat, A. R. Ghasemi,
Volume 7, Issue 3 (10-2003)
Abstract
The present study evaluates the influence of the El Ninio Southern Oscillation (ENSO) phenomenon on the cold season precipitation over Isfahan, Fars, Khuzestan, Chaharmahal-Bakhtyari, Bushehr and Kohgiluyeh-Boyerahmad provinces.
The results indicate that the occurrence of La Nina events caused a 20% to 50% reduction in precipitation over Bushehr, Chaharmahal-Bakhtyari and southern Fars. The cold event did not change the total precipitation over the other parts of the region. In contrast to La Nina episodes, the occurrence of El Ninio events caused a 20% to 70% increase in rainfall in most of the study area. While the most highly wet conditions are related to the El Ninio events, the occurrence probability of the severe droughts has found to be low during such events. In association with La Nina events, the occurrence probability of severe drought was found to be low. Only in Khuzestan and southern parts of the Fars Provinces, this probability has increased to about 0.5.
A. A. Barati, J. Mir Mohammad Sadeghi, A. Khatoonabadi,
Volume 8, Issue 2 (7-2004)
Abstract
Considering the population growth and limitation of expansion in cultivation areas, employment in non-agricultural jobs in rural areas is inevitable. The purpose of this study is to investigate the factors affecting the supply of labor of the rural families on non-agricultural jobs in the rural areas. A sample of 300 families from rural areas of the Ghoochan Township in 2000-2001 was studied. The data were collected through interviews and questionnaires. The analysis used a multivariable regression equation.
The results showed that: 1. The wage level of the non-agricultural experience of the person had positive effect on the supply of labors to non-agricultural jobs. 2. However, this effect was negative for the number of days the person worked on farm. Finally, since wages earned from non-agricultural jobs was higher than that of agricultural jobs. Therefore, it is suggested that for the purpose of increasing the income of rural people, non-agricultural jobs in rural areas be facilitated and encouraged
A. Khatoonabadi,
Volume 9, Issue 1 (4-2005)
Abstract
Public (or governmental) extension services suffer from its limitations and inadequacies to fulfill the requirements for sustainable farming practices. This study examines the aspects of practicing agricultural extension Privatization in Isfahan. The statistical sample society of the survey was the extension practitioners and technicians. Data were gathered through field questioning techniques and interpreted by the analytical methods of statistics in Isfahan province.
The result of the survey method on 105 agricultural extension agents and practitioners revealed that: 1) big farmers have more interest for private extension services than small farmers, 2) the more knowledgeable the farmers, the more demand for private advices 3) pest management, greenhouse production, mechanization and market information are given priority for private advisory services. Finally, "cooperative advisory service" was found to be the most relevant structure to motivate farmers' learning and consultancy activities.
F. Raiesi Gahrooee, E. Asadi, J. Mohammadi,
Volume 9, Issue 3 (10-2005)
Abstract
Over-grazing may induce changes in the dynamics of plant residue carbon and soil organic carbon (SOC). The objective of this study was to evaluate the litter quality of three dominant pasture species, and the relationship between litter quality and C dynamics under different range managements in native rangelands of SabzKou. Aboveground litters from three dominant species including, Agropyron intermedium (AP), Hordeum bulbosum (HB) and Juncus stenophylla (JU) were collected in an area protected from grazing for 15 years. Concentrations of N, P and K in litter samples were determined. Litter decomposition was also studied by using a litter bag experiment. Bagged litters were incubated under field conditions at grazed and ungrazed sites for one year. Concentrations of N in litters were 1.37, 1.36 and 0.98, respectively, for AP, JU and HB. Assuming 50 % C in the litter, C/N ratios of litters were 37.2, 37.3 and 51.1, respectively, for AP, JU and HB. The litters of AP, JU and HB contained, respectively, 0.13,0.12 and 0.21 % of P, and 1.04, 1.01 and 1.72 % of K. Results indicate no significant (p>0.05) and consistent difference in litter decomposition rates between grazed and ungrazed areas. The three pasture species, however, showed significant (p<0.01) differences in litter decomposition rate. It is appearing that the trend in litter decomposition of these plant species correlates initially with litter C/N ratio, but other quality parameters of litter as well as soil environmental conditions would likely affect the litter decomposability in advanced stages of decomposition process.
A. A. Azizi Zehan, A. A. Kamgar-Haghighi, A. R. Sepaskhah,
Volume 10, Issue 1 (4-2006)
Abstract
Iran with a cultivation area of 45000 ha and production of 150 ton/year is the number one saffron producer in the world. Planting of large size corms will increase flowering, but production of corms (number and size) may be affected by irrigation method or frequency. In this research which is performed in the farm of College of Agriculture, Shiraz University, the effects of method and frequency of irrigation on corm production, and the effect of produced corms on flowering were evaluated in two consecutive years. Two irrigation methods (basin and furrow) with four levels of irrigation frequencies (12, 24 and 36 days and dryland farming) were applied. In August of 2000 sample corm was taken from every plot, and the effect of applied treatment from previous growing period on corm production and the effect of produced corms on future flowering were evaluated and analyzed. Based on the results, in furrow irrigation, total number of corms and total number of corms smaller than 4 gr is significantly higher than basin irrigation. In all of the above cases, irrigation frequencies did not show a meaningful difference between themselves or in comparison with dryland farming treatment. Total weight of corms and number and weight of corms larger than 8 gr in basin irrigation were more than furrow irrigation. This is to the extent that it is considered as the main reason for the difference in the flowering of corms, and has caused the flowering of basin irrigation to be significantly higher than furrow irrigation. In basin irrigation, irrigation frequencies of 12 and 24 days had the highest amount of flowering. No significant difference was observed on average corm production between the treatments in the two irrigation methods. However, irrigation treatments in both irrigation methods showed significant differences when compared with dryland farming treatment. So, basin irrigation with irrigation frequency of 24 days is preferred over furrow irrigation due to lower water consumption and production of larger size corms which is effective in flowering.
S. H. Tabatabaei, H. Fardad, M. R. Neyshabory, A. Liaghat,
Volume 10, Issue 1 (4-2006)
Abstract
To determine the water application efficiency in furrow irrigation more accurately, consideration of seasonal and spatial variation of infiltration properties are needed. In addition, the effectiveness of different farm management on infiltration are significant. The main objective of this research was to simulate the seasonal variation (SV) of infiltration coefficients in Kostiakov-Louise equation (KLE) in a cracking soil under two traditional farm managements. Farm studies carried out in a clay-loam soil in Karaj. The two management treatments were soil without wheat residual and soil with wheat residual by a 5 ton/ha rate. There were 22 furrows with 0.75 m width in the farm. KLE infiltration coefficients were measured using inflow-outflow and two point’s methods in six furrows. The results of this study indicated that the SV of a and k coefficients were not significant, but variation of f0 was significant which was simulated with a logarithmic model. The effectiveness of SV on cumulative infiltration (Z) was also evaluated and indicated to be significant that were simulated with a logarithmic model too. Finally, dimensionless parameter such as Z* were developed to predicate Z parameter in different irrigation time, irrigation events and different residual management. Base on the result, although residue management causes a significant difference between value of f0 and Z in two treatments, but it doesn’t effect on trend of variation during the season. It means that the trend of variation is independent of residue in soil. It is probably done because of change in some of soil physical properties such as soil bulk density and aggregate stability.
A. R. Ommani, M. Chizari,
Volume 10, Issue 1 (4-2006)
Abstract
The main objective of this article is to present the results of a study done about the social, economical, and farming characteristics of wheat farmers in Khuzestan province of Iran regarding adoption of low input sustainable agriculture (LISA). LISA practices have tended to reduce the use of fertilizer pesticides, and maximal tillage, but, rely more on crop rotation, crop residues, animal manure, green manure, leguminous, appropriate mechanical cultivation or minimal tillage to optimize soil and natural pest control activity. The research design was a descriptive and correlation surveying method. Wheat farmers in Ahvaz, Behbahan, and Dezful township of Iran who cultivated wheat by the use of irrigation in the year of 1379-80 were the target population for this study. A random sample of wheat farmers selected from three randomly selected township of Ahvaz, Behbahan, and Dezful township (N = 5529 , n = 359 ). The main results of the study indicated that correlation of level of education, wheat land, ownership land , income, social participation, social status, social norm, technical knowledge, LISA knowledge, with adoption LISA practices were significantly positive and the correlation of age, experience in agriculture, distance between farm and service centers with adoption LISA practices were significantly negative.
A. M. Amini, M. Ramezani,
Volume 10, Issue 1 (4-2006)
Abstract
The general goal of this research was to study the effective factors on the success of the poultry-farm cooperatives in Isfahan province. Based on multi-stage cluster sampling and Chocran formulas, nine cooperatives and 173 members were selected from 15 cooperatives with 1768 members. After completion of questionnaires, the AHP method was employed for scaling. Statistical tests (factor analysis and alpha coefficient) indicated that this research has a high construction validity and reliability. The research results indicated that cooperative functions toward fulfillment of members' demands were weak. The results of the path model indicated that effective factors on the success of cooperatives (from highest to the lowest) are: knowledge of cooperative principles by the members, extra-organizational factors, education quality, managers' skills, participation in cooperative affairs, and members' education level. Also, the success of cooperatives much relies on inter-organizational factors. The amount of members' share from education, participation in cooperative's affairs, the managers' specialty and skills, and knowledge of cooperatives' principles are very weak. Research results indicated that there is a direct and statistically significant correlation between these independent variables and the success of cooperatives in Isfahan province.
R. Arefi, H. Nahvi, A. Hemat,
Volume 10, Issue 3 (10-2006)
Abstract
The objective of this research was to design and develope a Pick and Position system to displace spherical-shaped fruits, with minimum damage to flesh, from one specific place to another. A mechanical gripper (end-effector) suitable for grasping spherical-shaped fruits with 5-9 cm in diameter was designed and developed. The primary goal of the gripper design was to take and release the fruit without bruising it in a specified time sequence. A slider-crank mechanism was used to drive the gripper. To achieve suitable timing in gripping and releasing of the fruit, the slider was driven by a cam. The kinematic and dynamic analysis of the gripping unit was done and its motion was simulated using Working Modwl software. In the next step, a four-bar mechanism (arm) was designed and developed to displace gripper between two specified locations. After kinematic analysis, equation of motion of the arm mechanism was derived and its dynamic analysis was performed. The gripper was assembled on the arm mechanism and the performance of the gripper and arm mechanism was investigated. It was observed that the system had the ability to pick and release the oblong fruits, such as apple, between two specified locations. The performance of the system for larger size fruits could be improved by some modifications on the gripper fingers.
M. Mousavi, M. Chizari,
Volume 11, Issue 1 (4-2007)
Abstract
Potatoes are the third most important food crop in Iran. But fluctuations in the production of potato have made imbalances in supply and demand. Lack of appropriate planning for cultivation and marketing operation and farmers’ little knowledge of marketing provides a ground for uncertainty about marketing. To compete successfully in markets, knowledge on marketing is necessary. Succeeding in markets is possible by conducting the marketing educational programs. The broad objective of most marketing educational programs is to help producers modify production and marketing. The first stage in planning of marketing programs is to determine the educational needs. Therefore, needs assessment before planning and conducting to programs is necessary. In this study the educational needs of potato farmers regarding marketing have been considered. The descriptive- correlational research methodology was used in this study. The target population included potato farmers from Ajabshir Township, East Azerbaijan Province. A random sample of 110 potato farmers was selected by multistage cluster random sampling method for completing the questionnaires. Research results indicated that respondents’ technical knowledge in marketing is low especially in pricing and marketing. The most important educational needs of respondents were marketing and pre-harvest activities. The independent variables such as age, literacy rate, yield rate, experience of potato farming and size of potato farms did not have any significant relationship with educational needs. Based on respondents’ opinions, the best educational method was meeting agents on farm and conducting the educational courses.
A. M. Amini, A. Ahmadi, A. Papzan,
Volume 11, Issue 41 (10-2007)
Abstract
The purpose of this study was to assess characteristics of and reasons for farmers’ disagreement on implementation of land consolidation projects. Part of needed information was collected through questionnaire and interviewing 75 farmers in 6 unsuccessful villages in Kermanshah and Lenjanat region and also visiting some performed and ongoing projects. Other part of information was obtained by questionnaire and interviewing 44 experts involved with performing the project in Jahad Agricultural offices. Fragmentation of properties were measured by Januszewski fragmentation coefficient. Correlation coefficient and comparison of mean were used to analyzed the information. The results showed that disagreement of farmers is the most important obstacle for progress on land consolidatin projects, which accounted for farmers. In Lanjanat, these farmers have a better land structures in respect to size and fragmentation of parcels. In both rejoin reasons for farmer’s disagreement are divided in three groups: logical-justified reasons, logical-unjustified and illogical. Mediation, preference and legislative force are the three interactive methods to satisfy these farmers. To decrease disagreements and promote land consolidation in the two regions, following suggestions are offered: education and extension, correcting the technical and adminestrative methods of land consolidation and legal and judicial supports to implement the projects.
M.r. Tadayon, Y. Emam,
Volume 11, Issue 42 (1-2008)
Abstract
Photosynthesis and wheat grain yield responses to supplemental irrigation with different amount of applied water under dryland conditions were investigated. Therefore, a two-year field experiment was conducted research farm of College of Agriculture, Shiraz University during 2004-2005. Five levels of irrigation including dryland conditions, irrigation at stem elongation, booting, flowering and grain filling were main plots and two wheat cultivars: Agosta and Fin-15 were subplots, and three rates of nitrogen including zero, 40 and 80 kgha-1 were sub sub-plots. The results showed that in both years, photosynthetic rate, stomatal conductance, substomatal CO2 concentration and transpiration rate, were significantly higher under irrigation at stem elongation stage compared to other supplemental irrigation treatments. In all of the four supplemental irrigation treatments, photosynthetic rate, stomatal conductance, substomatal CO2 concentration and transpiration rate decreased with decreasing the amount of applied water to each plot. In both years, the highest grain yield was obtained from supplemental irrigation at stem elongation stage, and the lowest yield was harvested at dryland conditions. The highest photosynthetic parameters, yield and yield components were obtained from interaction of supplemental irrigation at stem elongation stage × Fin-15 and 80 kg N ha-1 in both years. The supplemental irrigation in 2004 and 2005 increased the grain yield 200 and 221 percent, respectively, compared to dryland conditions. Thus, supplemental irrigation at sensitive stem elongation stage could affect significantly wheat grain yield of rainfed wheat cultivars and provision of adequate water for a supplemental irrigation at the appropriate growth stage could double the grain yield of rainfed wheat.
A.a. Shahroudi , M. Chizari,
Volume 11, Issue 42 (1-2008)
Abstract
The purpose of this study was to investigate and analyze the factors affecting farmers’ attitudinal dimensions toward participation in Water Users’ Association (WUA) by comparing two groups of farmers in irrigation networks with WUA and without it. The methodological approach was a descriptive-correlational and causal-comparative study of the survey type. The target population in the study consisted of 2551 farmers of irrigation networks in Khorasan-e-Razavi Province, Iran. Using stratified random sampling technique, 335 participants were chosen. Data were collected through a questionnaire, and analyzed using SPSS, V.13. Content and face validity of the instrument were obtained by the faculty members of Agricultural Extension and Education, Agronomy and Irrigation Departments at Tarbiat Modarres University and also specialists board of Agricultural Jihad Organization and Regional Water Joint-stock Company in Khorasan-e-Razavi Province. The reliability analysis was conducted and cronbach’s alpha values for the various sections of instrument were estimated between 0.73 and 0.86. The descriptive findings of the study showed that the majority of farmers’ overall attitude with respect to participation in WUA was at a good level. The results obtained from Pearson correlation analysis indicated that there are significant and positive relationships between such variables as education level, size of irrigated cultivated landholding, annual income, extension contacts, social capital components, water users’ perceptions regarding irrigation networks status and farmers’ participation status concerning irrigation networks management with the farmers’ overall attitude toward participation in WUA. The result of stepwise multivariate regression analysis indicated that 61.1% (R2 = 0.611) of the variance in farmers’ attitudes with respect to participation in WUA could be explained by farmers’ behaviour regarding optimum farm water management, social participation, social confidence, water users’ perceptions regarding irrigation networks status, farmers’ participation status concerning irrigation networks management. Also, significant differences were found between the two respondent groups in irrigation networks with WUA and without it in relation to farmers’ attitudinal dimensions.
