Showing 36 results for Evaluation
H. Farhangfar, H. Naeemipour , R. Lotfi,
Volume 12, Issue 43 (4-2008)
Abstract
This study was undertaken to estimate genetic trend and parameters of Holstein cattle in Khorasan province for milk yield using a spline random regression test day animal model. A total of 32854 monthly test day milk records (twice and thrice a day milking) obtained from 3842 Holstein heifers (progeny of 466 sires) distributed in 125 herds and calved from 2001 to 2005 was used to predict breeding value of individual animals. In the model, fixed effects of herd including year-month of recording, milking times, age at calving (linear and quadratic covariables), Holstein gene percentage (linear covariable) as well as random effects of additive genetic and permanent environment were studied. To take account of the shape of the lactation curve at genetic and environmental levels, cubic spline polynomials were also included in the test day model. Bayesian method by applying Gibbs sampling technique (100000 chains applying RRGIBBS software) was utilized to obtain posterior means of predicted breeding value of animals for milk yield at individual month of lactation. The results showed that mean of breeding value for 305-day milk yield was 52.90 kg (p<0.05). Spearman rank correlations between predicted breeding values at different months of lactation decreased as the interval between them increased. The highest and lowest rank correlations were found between months 8 and 9 (0.998) and between months 1 and 10 (0.312), respectively. Predicted breeding value of 305-day milk had the lowest and highest rank correlations with predicted breeding value at months 1 (0.553) and 6 (0.990), respectively. Regression analysis of average predicted breeding value of progenies in their birth year showed that the amount of genetic trend for 305 day milk yield was 17.75 kg per year, statistically no different from zero (p value=0.165).
M. R. Bakhtiari, M. Loghavi,
Volume 12, Issue 44 (7-2008)
Abstract
In the conventional methods of herbicide and fertilizer application, a substantial amount of toxic chemicals is sprayed or broadcast into the furrows, which is later washed away by irrigation water and may contaminate ground water, human and animal environment. If herbicide and fertilizer application could be limited to the most needed parts of the field rather than overall broadcasting, the mentioned problems could be alleviated and the application efficiency could also be increased by reducing the consumption rate. In an attempt to achieve this goal, a combination cultivator capable of simultaneously performing cultivation practices such as weed control (mechanical + chemical), fertilizer application and pest control was developed and evaluated. This machine was able to perform band spraying (fungicide, insecticide and herbicide) and mechanical cultivation (within-the-row weed killing, furrow reforming and hilling) simultaneously and properly. The combination cultivator was able to reduce herbicide consumption up to 66%.
E. Abdi, B. Majnounian, A. A. Darvishsefat,
Volume 12, Issue 44 (7-2008)
Abstract
One of the most important cost factors in forest management, which involves a great deal of investment costs, is road construction. So evaluating forest roads and determining the best one can decrease costs. The objective of this study was to evaluate forest roads using Multi Criteria Evaluation with respect to costs. In Multi Criteria Evaluation method such factors as slope, aspect and soil type were used for suitability map. Then factors were compared in pair-wise comparison in the context of a decision-making process known as the Analytical Hierarchy Process (AHP) to develop weights of map layers. To do this, the opinions of some experts were collected using questionnaires and the results were integrated and factor weights were calculated. Then weights and their factors were entered into Multi Criteria Evaluation (MCE) Module to create final suitability map (factors were standardized before combining). Total costs of each variant were extracted from suitability map. After variant costs were obtained by dividing each variant total cost by its length, unit cost of each variant was calculated. Finally, unit costs were compared and the variant with the lowest costs was determined. The results showed that the slope had the greatest weight followed by soil and aspect. Also, variant 7 had the lowest cost and variant 8 the greatest cost. AHP method has the capability of considering qualitative and quantitative criteria so it is a proper method for weighting. Also MCE method in GIS environment has the capability of combining different factors. As it requires less time and cost, also has a higher precision, it is better to use MCE method in such studies.
M. Mardian, A. Najafinejad, J. Varvani, V. B. Sheikh1,
Volume 16, Issue 59 (4-2012)
Abstract
Investigation in to the sediment delivery of watersheds and its variation is an important element of ecosystem management. Since sediment load depends on runoff quantity, and runoff is considered as a unique indicator of sediment load, in this research the two modified versions of the MUSLE model were evaluated for 9 torrential events in two subwatersheds of the Kamal Saleh watershed in the Markazi Province of Iran. To this end, first all factors of the model including runoff, erodibility, topographic, cover management, and support practice were estimated using routine equations of the model. Then, the power coefficient in the runoff factor was corrected, applying two methods: “m correction coefficient” and “average correction coefficient. The evaluation criteria showed that the “m correction coefficient method” (compared to the “average correction coefficient method”) reduces the difference of the observed and estimated sediment load of small and large torrential events remarkably. In fact, the application of this modified method increased the accuracy of the MUSLE by decreasing the standard deviation of prediction. Also, the validation analysis of the modified method showed that the coefficient of efficiency indexes for the Hasan-Abad station (Rudkhane Bozorg subwatershed) and Ghal'e-No station (Ashur-abad subwateshed) were 0.997 and 0.811, respectively. This result confirms the efficiency of application of “m correction coefficient method”. However, it is suggested that the performance of this method be evaluated using a sufficient number of individual hydrographs and their sedimentgraphs in other watersheds.
Sh. Zamani, A. Parvaresh Rizi, S. Isapour,
Volume 17, Issue 66 (2-2014)
Abstract
Modernization of irrigation canals as an operation improvement tool is essential to promote the performance of canal networks and indeed requires control systems. Proportional integral derivative (PID) algorithms have more applications than the other controllers in different places of the world, but tuning these controllers for different hydraulic conditions of canals is considered as a major problem for designing control algorithms. Since the bottom slope is one of the effective factors in the water flow dynamic behavior, in this research, the distant downstream Proportional Integral Derivative feedback control with decouplers was designed with a change in longitudinal slope in a reference canal and its performance was investigated. The canal characteristics were used to tune this controller and the system identification as a new method was applied for determining canal characteristics. SOBEK hydrodynamic model modulated with MATLAB software was used to design and run the control algorithms, and slope influence on water flow behavior, tuning controller, and coefficients of controller were investigated with different values of slope. Then, controller performance for hypothetical period of operation in various scenarios was evaluated with computation performance indices. The results showed less resonance behavior of water flow and less potential of controller in steep slope
R. Mohammadi Motlagh, N. Jalalkamali, A. Jalalkamali,
Volume 18, Issue 67 (6-2014)
Abstract
The main scope of this research is evaluation of Soil Conservation Service Procedure in derivation of initial abstraction of precipitation in watershed scale. For this purpose Dalaki watershed which is located in south east of Iran was selected then by using hec-hms and GIS models and a number of observed rainfall runoff events some parameters like CN of watershed ,K and X of Muskingam method and initial abstraction of precipitation were calibrated through two different search algorithm of univariate and Nelder & Mead methods. The early results of this research indicated the superiority of Univariate search algorithm over the Nelder&Mead method both in calibration and also validation processes. Then using calibrated CN and Initial abstraction parameters which were derived through Univariate search algorithm, the factor between initial abstraction and potential retention of surface runoff (S) in each of sub basins were estimated. 0.13, 0.43 and 0.19 were derived as the above mentioned factor respectively for Minimum, Maximum and mean of the above mentioned factor in this step of the research which showed an acceptable compatibility to the offered factor of 0.2 by SCS. Then in rainfall runoff modeling process of this watershed SCS offers a reliable method of initial abstraction estimation.
Y. Nabipoor, M. Vafakhah, H. R. Moradi,
Volume 18, Issue 67 (6-2014)
Abstract
The occurrence trend of floods in recent years shows that the most of Iran regions located in attacks of destructive floods and loss of life and property of flood damages is increasing. Watershed management practices (WMPs) are one of the superior and appropriate solutions for flood hazards mitigation. The impact of WMPs can be investigated using different approaches. In this study, the direct impact of WMPs was investigated using quantitative evaluation of flood characteristics for two periods, pre and post periods of measures implementation. Therefore, daily hydrograph of investigated periods and the results of flood analyses including number of floods occurrence, flood frequency percent in the different months and seasons were determined in Hajighoshan and Tamar hydrometery stations. Also, the mean continuing, rise and subsidence time of floods and maximum peak discharge of observed floods were investigated. The research results showed that the occurrence trend of floods had relatively increased. The number of floods has increased in post periods of measures implementation in two hydrometery stations, while WMPs effect on all flood characteristics were positive, as the continuing time of floods has increased with 0.5%, rise and subsidence time of floods and maximum peak discharge of floods have decreased with 7.9%, 21.98% and 70%, respectively. Totally, if WMPs volume pre watershed area isn't low, WMPs effect on flood characteristics will be positive.
I. Esfandiarpour Boroujeni, Y. Safari,
Volume 18, Issue 67 (6-2014)
Abstract
Comparison of the land suitability variations among the soil map units in viewpoint of pedodiversity indices may provide a good assessment of the soil mapping precision. The main objective of this study was to assess the significance of functional pedodiversity thorough two detailed map units for irrigated wheat and potato for class and subclass levels of suitability in the Faradonbeh plain, using Shannon and Simpson indices. First, soil samples at 35 and 47 sampling sites in the D and E map units, respectively, were collected from the depths of 0-25, 25-50, 50-75 and 75-100 cm. Then, the qualitative land suitability class and subclass of all sampling points for each studied land use, was evaluated based on simple limitation method. Although both indices showed higher values in the subclass level of suitability, but the average functional pedodiversity of the studied map units, indicate a significant difference (95% confidence level), just in this suitability level. It was observed that the significance of the pedodiversity indices is not influenced by the land use type or the analyzed diversity index. Hence, as a supplementary procedure to study the intra-unit variation of the soil maps, use of diversity indices may provide some worthwhile information
B. Moumeni, M. Masoudian, M. A. Gholami Sefidkohi, A. Emadi,
Volume 22, Issue 3 (11-2018)
Abstract
Over the years, since the beginning of the national and infrastructural project of Development and Renovation of Paddy Fields of Iranian Northern provinces, it has been essential to evaluate water distribution and delivery Performance of the project to get its feedback in the pursuit of the desired goals. However, the results of the evaluation of a system can reliable when they are based on quantitative indicators, not on personal opinions and empirical judgment. So, in this study, Total Error (TE) of performance of water delivery system, a statistical indicator, and its component including adequacy, water management capability and equity errors were calculated and compared for two concrete and earthen irrigation canals. This analysis was done based on calculating water demand and measuring the volume of delivered water between outlets during the irrigation season in the paddy fields of Esmaelkola of Joybar city, in 2015. According to the results, although the concrete channel (0.28) had less error than the earthen channel (0.43) and in the concrete channel, as compared to the earthen channel, the share of the components of adequacy and water management capability from the total error was dropped from 47% to less than 10%, but the error in the water delivery of the concrete channel was still high due to the error in the equity of distribution, whose value was 0.25 (90% of the total error). Therefore, in order to reduce the performance error, after channel lining, it would be necessary to make fundamental changes in the intake and flow control structure in addition to the training of irrigators regarding water delivery based on water demand.
F. Soroush, B. Mostafazadeh-Fard, S. F. Mousavi, F. Abbasi,
Volume 23, Issue 1 (6-2019)
Abstract
Infiltration is the most important characteristic in the design and management of any surface irrigation system. Since the hydraulic of flow in meandering furrows is different from the standard furrows, the accuracy of infiltration function parameter estimation methods should be examined for the optimal design and management of meandering furrow irrigation. The main objective of this study was to compare Elliot and Walker’s two-point and two-time methods for estimating the empirical infiltration function parameters of meandering furrow irrigation using four sets of field data. The estimated infiltration functions, as obtained by the two methods, were validated by performing the unsteady flow simulations and using the Slow-change/slow-flow (SC/SF) model. The results showed that Elliot and Walker prediction of the advance trajectories (with a mean RMSE of 0.68 minutes) was comparable to the two-time method (with an average RMSE of 0.66 min). The Nash–Sutcliffe efficiency coefficient for the simulated outflow hydrograph by the two-time and two-point methods was 0.89 and 0.50, respectively, indicating the excellent predictive power of the two-times method. In addition, the two-time method predicted the total volume of infiltration with the less relative error (-1.5%), in comparison to the two-point method (-47.2%). Therefore, the use of post-advance data (such as a two-time method) for infiltration function parameters estimation improves the flow simulation in the meandering furrows.
A. R. Zahirnia, H. R. Matinfar,
Volume 23, Issue 2 (9-2019)
Abstract
Determination of land suitability is one of the land evaluation methods that can determine the best use of land in each area. The purpose of this research was to determine the land suitability of Mirza Kuchak Khan's cultivation and industry fields based on the soil quality indicators and a geographic information system (GIS), and compare the results with those obtained by methods of land evaluation and root strategies. For this purpose, information on soil profiles and the amount of organic matter, phosphorus, nitrogen, potassium, zinc, drainage, texture, depth, topography, surface rocks and gravel, impervious layer depth, hydraulic conductivity, water holding capacity, electrical conductivity, reaction PH), calcium carbonate, and exchangeable sodium percent of the study area were collected. Land suitability classes based on the quality indices of fertility, chemical quality, and physical quality of soil were defined. The results showed that 27.4% of the land belonged to the very good class (S1), 62.83% of the land could be assigned to the suitable class (S2), 11.7% of the land was put in the low proportion class (S3), and 2.66% the land was in the inappropriate class (N). Also, based on the comparison of the results of the method based on the soil quality with the square root method, Kappa coefficient was 0.82, while it was equal to 0.38 for the Storie method.
A. Kaghazchi, S. M. Hashemy Shahdany, A. Roozbahany, M. E. Banihabib,
Volume 24, Issue 3 (11-2020)
Abstract
The main purpose of the study is the operational simulation of main irrigation canal and evaluation of water delivery and distribution locally, regionally and overall using adequacy, efficiency, and equity indicators and “Desirability of water delivery and distribution” indicator. To achieve this goal, the hydrodynamic model of Roodasht irrigation network’s main canal was developed. The results of the calibration and validation of the hydrodynamic model showed that the two processes were satisfactory. All available scenarios including normal, water shortages and fluctuations were considered for water delivery and distribution in different conditions. In the local assessment, the adequacy varied from 7 to 85%, and the efficiency in all scenarios was 100%. The adequacy, efficiency, and equity indicators in the regional evaluation varied from 6 to 89, 91 to 100, and 13 to 46%, respectively. The overall evaluation of the canal showed that the most desirable situation is related to a harsh fluctuation increasing with the adequacy, equity and efficiency indicators equal to 82, 23 and 91%, respectively. Calculation of the “Desirability of water delivery and distribution” indicator showed poor performance in all operational scenarios except harsh fluctuation scenario with 82% of which, the canal performance was estimated in fair level.
H. Fazlolahi, R. Fatahi, K. Ebrahimi,
Volume 25, Issue 1 (5-2021)
Abstract
Water is the most crucial factor for agricultural development. Therefore, the economic evaluation of water resources is critical. The purpose of this paper was to determine the economic value of water resources, to evaluate the financial efficiency and to decide on the price of agricultural water in Arak plain. For this purpose, the economic value of water resources for wheat, barley, alfalfa and corn was identified in 2015- 2016, using the mathematical model developed in this research. The results showed that the financial efficiency was calculated for three alternatives: free-cost water, water cost equal to the 10% of the calculated price and water cost equal to the exact calculated price. The irrigation efficiency of 40% financial efficiency was 2.38%, 1.68% and 0.47% , respectively, for the aformentioned methods, and the irrigation efficiency of 70% financial efficiency was 2.07, 1.92 and 0.71, respectively. Also, the sensitivity analysis of the financial efficiency was performed, with 10% change in the farmers income and costs. The results also revealed that irrigation efficiency and financial efficiency were not aligned when farmers had free water; however, they were aligned when the farmer paid 10% of the calculated price. Financial efficiency was more sensitive to changes in the farmers income when compared to the changes in costs.
M. Sabouri, A.r. Emadi, R. Fazloula,
Volume 26, Issue 2 (9-2022)
Abstract
A compound sharp-crested weir is often used to measure a wide range of flows with appropriate accuracy in open channels. In this study, experiments were performed to investigate the hydraulic flow through a compound weir of circular-rectangular with changes in hydraulic and geometric parameters in free and submerged flow conditions. The characteristics of the weirs include rectangular spans width of 39 cm, a circular radius of 5, 7.5, and 12.5 cm, and heights of 10 and 15 cm. The results showed that by increasing the radius and height of the Weir, upstream water depth increases around 28.4%. At a constant h/p, the discharge coefficient increases with the increasing radius of the circular arc. Also, in the submerged conditions, the discharge coefficient is less (around 40%) than in the free flow condition, which is due to the resistance of the depth of the created stream against the passage of the flow.
P. Papan, M. Albaji, R Kh. Peyghan,
Volume 27, Issue 1 (5-2023)
Abstract
Population growth and limited water and soil resources make it necessary to pay attention to the factors affecting food production, including the suitability of irrigation methods with agricultural lands. The objective of this study was to assess land suitability for surface, drip, and sprinkler irrigation methods based on a parametric evaluation system in an area of 250 hectares in the Shahid Rajaei plain of Khuzestan. Soil properties were analyzed, then suitability maps for different irrigation methods were prepared using a geographic information system (GIS). The results showed that for surface irrigation, 704 ha (31.3%) was marginally suitable (S3), 866 ha (38.5%) was currently not suitable (N1), and 680 ha (30.2%) was permanently not suitable (N2). For drip irrigation, 8 hectares (0.4%) are highly suitable (S1), 644 hectares (28.6%) are moderately suitable (S2), 52 hectares (2.3%) are marginally suitable (S3), 866 hectares (38.5%) were currently not suitable (N1), and 680 hectares (30.2%) were permanently not suitable (N2). For sprinkler irrigation, 652 hectares (29%) are moderately suitable (S2), 52 hectares (2.3%) are marginally suitable (S3), 866 hectares (38.5%) are currently not suitable (N1), and 680 hectares (30.2%) were permanently not suitable (N2). According to the results, sprinkler irrigation with an irrigation capability index of 29.9 to 60.7 in 2242 hectares (99.6%) is preferable to other irrigation methods. Drip irrigation in 8 hectares (0.4%) was found to be the most suitable method. The main limiting factors in using all three irrigation methods included salinity, alkalinity, and drainage. Also, soil calcium carbonate was added to the limiting factors in drip irrigation.
R. Dabiri, H. Abghari, A. Ghorbani,
Volume 27, Issue 4 (12-2023)
Abstract
Management of watersheds and sustainable development today requires the most suitable and fastest method of obtaining and integrating information for optimal management and planning. One of the challenges of watershed management in the stage of planning and implementation of remedial and rehabilitation operations is choosing the appropriate and correct location; to have the necessary maximum efficiency and effectiveness, due to the high cost of mechanical operations and the lack of financial resources, select the right place to construct mechanical corrective dams has particular importance. Therefore, the objective of this research was to locate mechanical watershed management operations with a multi-criteria approach using AHP and ANP decision methods and compare the two methods in the geographic information system environment at the Saqezchi-Chay watershed. The research criteria and sub-criteria of 14 variables included soil (depth and texture), climate (type and precipitation amount), land use and Normalized Difference Vegetation Index (NDVI), hydrological factors and soil protection (flow accumulation, sedimentation rate, and curve number), topography (elevation and slope) and economic and social (distance from the village, from loan sources and the road). Expert judgments for weighting were collected through a questionnaire and in a field method with a statistical population of 29 experts and university professors. The results of this research showed that the ANP method had a significant correlation with the AHP method at the level of 95% and with an intensity of 0.839 and by comparing the prioritization of the two methods with Masonry Check Dams structures implemented in the Saqezchi-Chay watershed, it was determined that the ANP method prioritizes with more accuracy and resolution due to its network nature and increasing the range of changes.
