Showing 27 results for Moghaddam
J. Jafarzadeh, A. Babai-Ahari, M. Moghaddam Vahed, M. Valizadeh, H. Kazemi, H. Ghazvini,
Volume 9, Issue 1 (spring 2005)
Abstract
The reaction of forty two barely landraces, mostly from Azarbijan Province and a susceptible cultivar, Zarjo, was studied under greenhouse conditions in the presence of four highly virulent isolates of Pyrenophora graminea, i.e. Marand 3, Ajabshir 2, Khasseban-Tireh, and Bostanabad. The experimental design was a split-plot based on randomized complete blocks with three replications. Landraces were considered as sub-plots and the isolates as whole plots. The seeds were inoculated by the sandwich method and responses of the landraces were evaluated by the method of Mathur and Bhatnagar. The resistance of landrace #1 to the isolates of Marand 3 and Ajabshir 2 and that of landrace # 27 to the isolate of Ajabshir 2 was observed. These landraces could be used as a source of vertical resistance in barley. Landraces 6, 8, 11, 12, 13, 15, 17, 25, 27, 28, 29, 31, 33, 34, 36, 37 and 41 were classified within the range of partial resistance to partial susceptibility, which may be utilized as the sources of horizontal resistance.
M. M. Nakhjavani Moghaddam, B. Ghahraman,
Volume 9, Issue 3 (fall 2005)
Abstract
In order to determine the water production functions for winter wheat (Variety, C73,5), an experiment was conducted in through of a complete randomized block design with 9 treatments and 3 replications in Mashhad region. While the first treatment (as a control treatment) was selected on the basis of irrigation in all growth stages of growing season, six treatments were selected on the basis of an irrigation cut in the six stages of growth season and two remaining treatments were also selected on the basis of a constant reduction of irrigation to the amount of 20 and 60 percent. In general the water stress was caused that the amounts of depth percolation were calculated negatively which was an indication of the water uptake from below the root zone. According to results, models of the yield in per unit of area had a higher correlation coefficient of determination in relation to the models of the yield in per unit of water. The derived sensitivity coefficients indicated that the winter grain formation and flowering stages were respectively the most sensitive stages of the growth season stages to the water deficit. There are some differences between these computed sensitivity coefficients and the amounts reported by the other researchers. Probably the variety, degree of stress, the climatic conditions and some unknown factors may explain these differences.
M. Rezaei, H. Nassiri Moghaddam, J. Pourreza, H. Kermanshahi,
Volume 9, Issue 4 (winter 2006)
Abstract
An experiment was conducted with the male Ross broiler chicks from 1 to 42 days of age to test the effects of different dietary protein and lysine levels on performance, carcass characteristics, and N excretion. Treatment diets consisted of three levels of supplemental lysine in starter and grower period (0, 0.15, and 0.30 %) and the two levels of protein (20.84, 17.84 in starter, and 18.12, 16.12% in grower period) with 2900 Kcal ME/kg diet. The results indicated that the Reducing dietary protein decreased significantly the weight gain in starter, grower, and total period up to 6, 4.6, and 5.6%respectively (P<0.05). It also decreased the feed consumption in starter period (P<0.05). Decreasing dietary protein had no significant effect on gain to feed ratio and breast meat yield, but increased abdominal fat percentage significantly (P<0.05). Increasing dietary lysine increased the feed consumption in starter and weight gain, gain to feed ratio in grower and total period of the experiment (P<0.05). Increasing lysine in diet caused a significant increase in breast meat and tight yield, and percentage. Adding supplemental lysine reduced the N excretion in starter period significantly (P<0.059). N excretion reduced significantly by decreasing dietary protein (P <0.05). Dietary treatments had not significant effect on mortality percentage. The results of the present experiment indicated that with providing limiting amino acids and adding supplemental lysine to diet, the crude protein could be reduced up to 3 and 2 percent in starter and grower periods respectively. Reducing the crude protein had not adverse effect on the feed efficiency.
A. Hassanabadi, H. Nassiri Moghaddam, H. Kermanshahi, J. Pourreza, D. Korver,
Volume 9, Issue 4 (winter 2006)
Abstract
In the current experiment seven catheterized broiler breeder hens were used at 60 weeks of age. Retention of 14CO2 in the body of the hens following continuous infusion of NaH14CO3 during each of tow-30-hr continuous infusion studies was determined. Oxidation rate plateau was established within two hours in each experiment. Recovery of 14CO2 at the steady state in the first and second study were 91.09 and 87.55 percent respectively and were not significantly different. Mean breath 14CO2 recovery was 89.32 percent and hence retention was 10.68 percent. Recovery of 14CO2 in breath was not significantly affected by laying of egg or photoperiod. Recovery of 14CO2 during the fed state was significantly lower than the fasted state. The results of this experiment indicated that, using of uncorrected data for the retained isotope into body, lead to 10.68 percent AA requirements underestimation in broiler breeder hens by indicator amino acid oxidation technique.
E. Karami, K. Rezaei- Moghaddam, H. Ebrahimi,
Volume 10, Issue 1 (spring 2006)
Abstract
Increasing the water use efficiency through promotion of sprinkler irrigation system, in order to increase production, has been the aim of the Ministry of Agricultural-Jihad in the past decade. Considerable amount of investment and efforts have been devoted to this end. Therefore, investigation of these efforts and development of models to predict the adoption behavior of farmers are of considerable importance. A survey research was conducted in four provinces (Fars, Bushehr, Kohkiloye-va-Boyerahmad, and Chaharmahal-va-Bakhteyari). A stratified random sample of 422 farmers was interviewed including 124 and 298 adopters and non-adopters, respectively. The findings indicated that the discriminant model developed based on the multiplicity model is a better predictor of farmers’ adoption behavior than diffusion and farm structure model. Application of multiplicity model in extension of sprinkler irrigation can increase the adoption rate and as result the efficiency of extension efforts.
Gh. Mohammadi, K. Ghasemi Golezani, A. Javanshir, M. Moghaddam,
Volume 10, Issue 2 (summer 2006)
Abstract
In order to investigate the effect of different irrigation regimes on some agronomic and physiological characters of three chickpea cultivars (Jam, 301 and Pirooz), a field experiment was conducted in 1998 at the Agricultural Research Farm of Tabriz University, Tabriz, Iran. A split plot experiment based on a randomized complete block design with three replications was used, in which irrigation treatments (full irrigation, irrigation at only branching or flowering and or pod formation stage) were in the main plots and chickpea cultivars were in the sub plots. Under limited irrigation conditions there were no significant differences among irrigation regimes for green cover percentage and the number of pods per plant while rate and duration of grain filling, grain weight and grain yield were significantly higher for irrigation at pod formation than for irrigation at branching or flowering stage. The mean of all the traits, except for the number of seeds per pod were significantly higher for full irrigation than for limited irrigation treatments. Rate of grain filling, maximum grain weight and grain yield were significantly higher for irrigation at flowering than for irrigation at branching stage. While, other characters were not significantly different between these two treatments. Although, green cover percentage and seeds per pod in 301 were higher than those in Jam, but in other cases their response to water limitation was almost similar. All traits, except the number pods per plant, were noticeably lower for Pirooz compared to Jam and 301 cultivars. Green cover percentage showed the highest correlation with the grain yield. This study revealed that among phenological stages of chickpea, pod formation is the most sensitive to water deficit, and that under water limitation conditions chickpea yield could be improved by irrigation at this stage.
M. Bahar, S. Ghobadi, V. Erfani Moghaddam, A. Yamchi, M. Talebi Bedaf, M. M. Kaboli, A. A. Mokhtarzadeh,
Volume 10, Issue 2 (summer 2006)
Abstract
To determine genetic diversity among some Iranian local varieties of alfalfa, six geographically diverse populations including: Bami, Rahnani, Nikshahri, Yazdi, Hamadani (from Isfahan), Hamadani (from Shiraz) along with Ranger, an American commercial variety, were evaluated using a set of 24 EST-SSR primers developed from cDNA library of Medicago truncatula and three microsatellite loci, identified from genomic library of M. sativa. Of the pairs of primers tested, four loci from EST-SSRs (AW9, BEE, TC6 and TC7) and genomic microsatellite (Afctt32), were found appropriate for assessing genetic diversity between these alfalfa genotypes. In total, 46 alleles were detected from the five loci in the samples of alfalfa examined. The number of alleles per locus in populations ranged from six to eleven and genetic diversity indices of loci were variable from 0.62 to 0.87 for the populations. Genetic relationship analysis of EST-SSR data revealed separation of Iranian populations from Ranger. It is likely that the parental origin of primary population from which Ranger has been derived is different from that of Iranian populations. Iranian local populations of alfalfa in this study were grouped in two main clusters. Alfalfa populations Hamadani and Rahnani, which are adapted to cold claimates, were grouped in one cluster and populations Bami, Yazdi and Nikshahri, belonging to the trpoical areas, were placed in the next cluster. The positioning of EST-SSR loci in coding regions of genome, possibly increases the usefulness of these markers to clarify inter specific genetic relationships among alfalfa populations.
M. Jamshid Moghaddam, S. S. Pourdad,
Volume 10, Issue 2 (summer 2006)
Abstract
To evaluate seed germination and seedling growth of safflower in moisture stress, germination of 15 genotypes at four water potential levels (ψ: 0, -0.4, -0.8 and –1.2 Mpa) was tested by Polyethylene glycol (PEG6000). Maximum germination (Gmax), germination rate index (GRI), time length to reach 50% germination (T50), rootlet length (RL) and shootlet length (SL) were investigated. Effects of water potential levels and genotypes were significant for all the characteristics studied. Minimum water potential for germination was estimated between –1.17 and –1.59 Mpa in Goshkhani and LRV-51-51 genotypes, respectively. Different responses to moisture stress were found for rootlet length. In lower potential levels, seedlings had longer, weaker and thiner rootlets in comparison to the zero water potential (control). An increase in stress to –1.2 Mpa led to a severe reduction in rootlet elongation. All stress levels decreased GRI and SL, while potentials lower than –0.4 Mpa decreased Gmax. With a decrease in water potential from 0 to –0.8 Mpa, the T50stage was delayed three-fold compared to the control. Exotic genotypes had longer T50 stage than Iranian genotypes. The highest GRI was related to three Iranian genotypes LRV-51-51, Varamin 295, and Isfahan local, and the lowest was related to CW-74 exotic genotype. Some of genotypes were evaluated for seed yield, oil yield and seed oil percentage under rainfed condition in 2004-05. The highest oil yield average belonged to two exotic genotypes PI- 537598 and Lesaf (326.4 and 313.9 Kg/ha, respectively) and the least was related to Zarqhan 279 Iranian genotype (133.2 Kg/ha). Negative and significant correlation was observed between seed oil percentage and GRI in the 0, -0.8 Mpa potential levels. According to the results, the existing genetic variation for germination parameters can be used for genetic improvement of seed early vigor in safflower.
A. Sarkhosh, Z. Zamani, M. R. Fatahi Moghaddam, A. Ebadi, A. Saie, S. Z. Tabatabaie, M. R. Akrami,
Volume 10, Issue 4 (winter 2007)
Abstract
In order to determine the most important quantitative and qualitative characteristics of pomegranate fruit and its components for categorizing the genotypes, a study was carried out using 24 genotypes. In this study 28 quantitative and qualitative characteristics of pomegranate fruit and seed were evaluated. Analysis of variance showed that all of the characteristics in examined genotypes were significant, showing high variability in characteristics. Results of simple correlation analysis showed the existence of significant, positive and negative correlations among some important characteristics. Also, factor analysis showed that most of fruit juice, aril and seed characteristics constituted the main factors. Effective characteristics categorized in seven factors accounted for 89% of total variance. For each factor, eigen value more than 0.7 was considered significant. Cluster analysis was performed using these seven factors and genotypes, in the distance of 9, were divided into 5 main clusters. These groups were mainly distinct in fruit flavor and soft seededness. Furthermore, by using three main factors, genotypes positions determined in 3-plot analysis, which distinguished sweeter genotypes from sweet-sour and sour genotypes.
M.. Toorchi, S. Aharizad, M. Moghaddam, F. Etedali, S. H. Tabatabavakil,
Volume 11, Issue 40 (summer 2007)
Abstract
Sainfoin in believed as an important forage crop regarding its suitable agronomical characteristics and feeding livestock. Evaluation of general combining ability is a critical preliminary stage before selection of suitable parent and production of synthetic varieties. Thirty six sainfoin landraces which have been collected from different parts of Iran were grown in 2000 in a randomized complete block design (RCBD) with 24 replications as a polycross nursery. The resulting polycrosses were sown in 2001 in a triple lattice design. Characters such as fresh forage yield per plot based on unit length, fresh forage yield per plant, and dry forage yield for each cutting stage and for the whole season were measured. Also a yield index for the two first cuttings and forage palatability for the second cutting were determined. Results showed that there was no significant difference between partial blocks within each replication and therefore data was analyzed based on RCBD. High heritability was observed for forage palatability, yield index, and fresh forage yield per plant. So selection can be made to improve forage yield and palatibility in sainfoin. In terms of general combining ability, six landraces for fresh forage yield, six landraces for dry forage yield, nine landraces for yield index, and ten landraces for palatibility showed high estimates. The lanraces having highest amounts of general combining ability for each variable can be used as suitable parents to produce synthetic varieties of sainfoin.
O. Khademi, Y. Moustofi, Z. Zamani , M.r. Fatahi Moghaddam,
Volume 12, Issue 43 (spring 2008)
Abstract
In this experiment the response of persimmon fruit, cv. Karaj, to astringency removal by ethanol and the effects of this treatment on some important fruit characteristics were investigated. Fruits were harvested at three different dates and at each date based on the previous results, and then modified treatments were applied. The best ethanol astringency removal treatment in this study was 10 ml of 38% ethanol per kg fruit for 48 hours. The period after ethanol treatments had no effect on the reduction of soluble tannin concentration, although it resulted in the reduction of flesh firmness and increased soluble pectin. Ethanol treatments and also temperature conditions reduced flesh firmness and increased ground color of fruits however, the effect of ethanol treatments was more than temperature conditions. Temperature conditions increased ethylene production, thus reducing the flesh firmness and increasing the ground color index of fruits. Ethanol treatments did not increase the ethylene production, and it seems that its effects on some characteristics are due to ethanol itself or factors other than ethylene.
J. Erfani Moghaddam, A. Ebadi, M. Fatahi Moghaddam,
Volume 12, Issue 45 (fall 2008)
Abstract
Seedlessness is the most important characteristic of fruit quality for raisin and table grapes. Grape breeding at University of Tehran, Karaj branch, Iran started in 1999 with crossing some selected seedless and seeded cultivars at the end of evaluation of 90 cultivars in grapevine collection of College of Agriculture in Karaj. Out of 1400 progeny obtained from 26 different crosses, 381 of them which produced fruits were evaluated during growing seasons of 2006 & 2007. Progenies were divided into four groups of completely seedless, semi-seedless, semi-seeded and completely seeded, according to seed trace or seed weight. Results classified progeny to 11% completely seedless, 13.6% semi-seedless, 24% semi seeded and 51.2% completely seeded. Percentages of seedless progeny for four male parents of Askary, Yaghooti, Bidane Sefid and Bidane Ghermez were 15.4%, 10.8%, 9.3% and 10.6%, respectively. Meanwhile, percentages of seedless progeny for female parents of Muscut of Hamburg, Ghezel Uzum, Dizmary, Rajabi Sefied, Ali Baba, Alhaghi Ghermez and Tabariz were 5.4%, 5%, 17.5%, 13.2 %, 1.4%, zero and 36%, respectively. Results also showed that among male parents, Yaghooti and Bidane Ghermez cultivars and among female parents, Tabarze cultivar had better backgrounds to transmit stenospermocarpic seedlessness characteristics.
M. Karami Moghaddam, M. Shafai Bajestan, H. Sedghi,
Volume 15, Issue 57 (fall 2011)
Abstract
In diversion flows, a portion of stream flow which enters the intake is diverted from upstream of the intake denoted by a surface and is called dividing stream surface (DSS). The amount of flow and sediment discharge entering the intake as well as design of submerged vanes to control sediment depends on determination of dividing stream width. In this study, the experimental tests were carried out at a 30 degree water intake from a trapezoidal section. Three components of velocity data were obtained for different flow conditions. Then numerical SSIIM2 model was calibrated and verified using tests data. More flow conditions such as the main channel with rectangular section were run using SSIIM2 model to get enough hydraulic data. From analysis of these datas it was found that the dividing stream width in different distances from the bed depends directly upon the diversion flow ratio. It was found that in comparison to the rectangular section, in trapezoidal cross section, the DSS dimensions are modified in such a way that its width is increases at the surface and reduced at the bed for the same flow conditions. Relations for predicting the dividing stream width and diversion flow ratio have been presented in this paper for intake from both rectangular and trapezoidal cross sections.
M. Esfahani Moghaddam, A. Fotovat, Gh. Haghnia,
Volume 16, Issue 59 (spring 2012)
Abstract
Silver toxicity and its fate in the environment are currently being debated and are important as challenging research topics. Even though there are several studies on its total content in soils, fractionation of Ag especially in calcareous soils has not been investigated. Therefore, to provide fundamental information on the chemical behavior of Ag in calcareous and noncalcareous soils, we studied 8-step chemical fractions of Ag (i.e., EXCH, CARB, Me-Org, re-MeOx, H2O2-Org, am-MeOx, cr-FeOx, and RES) after 30 and 60 days of incubation in soils amended with Ag (0 and 15 mg kg-1), sewage sludge (0 and 20 t ha-1) and EDTA (0 and 0.5%). Experimental results showed that redistribution of Ag in spiked noncalcareous soils was EXCH (34%), H2O2-Org (33%) and RES (17%). In calcareous soils, after 30 days, EXCH- and RES-Ag increased but at the end of 60 days H2O2-Org-Ag increased. Based on our data, we could conclude that addition of Ag results in an increase of Ag mobility in soils but incubation and sewage sludge may have adverse effect on its mobility. In contrast to noncalcareous soil, EDTA in calcareous soil resulted in higher Ag mobility. This may have environmental implications in Ag polluted calcareous soils.
Sh. Ghorbani Dashtaki, S. Dehghani Baniani, H. Khodaverdiloo, J. Mohammadi, B. Khalilmoghaddam,
Volume 16, Issue 60 (Summer 2012)
Abstract
Saturated hydraulic conductivity (Kfs) and macroscopic capillary length of soil pores are important hydraulic properties for water flow and solute transport modeling. Measuring these parameters is tedious, time consuming and expensive. One way is using indirect methods such as Pedotransfer functions (PTFs). The objective of this research was to develop some PTFs for estimating saturated hydraulic conductivity and inverse of macroscopic capillary length parameters (*). Therefore, the coefficients, Kfs and * from 60 points of Azadegan plain in Shahrekord were measured using single ring and multiple constant head method. Also, some of the readily available soil parameters from the two first pedogenic layers of the soils were obtained. Then, the desired PTFs were developed using stepwise multiple linear regression. The accuracy and reliability of the derived PTFs were evaluated using root mean square error (RMSE), mean error (ME), relative error (RE) and Pearson correlation coefficient (r). The highest correlation coefficients of 0.92 and 0.72 were found between Kfs-bulk density and *-bulk density, respectively. There was no significant correlation between soil particle size distribution and Kfs and *. This can be related to the fact that most of the soil samples were similar in texture and macro pores. The most efficient PTFs in predicting Kfs and * could explain 85 and 66 percent of the variability of these parameters, respectively. All the derived PTFs underestimated the Kfs and * parameters.
M. Ebrahimi, M. Jafari, E. Rouhimoghaddam,
Volume 19, Issue 72 (summer 2015)
Abstract
The present study was conducted to increase phytoextraction efficiency of Festuca ovina L. in lead contaminated soil in the EDTA-assisted (0, 1.5, 3, 1.5+1.5, 3+3, 6 mmol kg−1), assess the best time of plant harvesting to increase Pb uptake and method of EDTA application to reduce Pb leaching risk. The results revealed that the greatest Pb uptake was observed in 3EDTA treatment. Therefore, 3mmolkg-1 was used in the second step for assessing harvest time for 15, 30 and 45 days. Results showed that the concentration of Pb in plant tissues was increased with the passage of time and the best harvest time to achieve maximum removal of Pb was 60 days of the first harvest. In the third step to reduce leaching of Pb-chelate, 3mmolkg-1 EDTA in five ways of single, double, triple, quadruplet, quintuplet were added to the soil. The results indicated that under quintuplet application, Pb content reached its minimum concentration in the soil and in the plant organs, the Pb concentration was maximum and metal concentration in the plant organs did not vary significantly when triple, quadruplet and quintuplet dosages were added (p<5%). Overall, optimum phytoextraction of F. ovina L. and Pb leaching reduction were achieved when 3mmol kg−1 EDTA was added in quintuplet dosage and the plant was harvested at the end of growth stage.
Z. Sorkheh, B. Khalili Moghaddam,
Volume 22, Issue 1 (Spring 2018)
Abstract
The purpose of this research was to study the effects kerosene by a factorial experiment in the nested design in three replications. The factors included region (Shush, Dezful and Bavi), plant (parsley, dill, coriander and carrot), and management practice (control, contaminated field with kerosene 1, contaminated field with kerosene 2). Heavy metals concentration (Pb, Zn, Cu and Cd) was measured in soil (DTPA extraction method) and plants samples. The results indicated that the average values of the heavy metals concentration in both soil and plants samples subjected to kerosene contaminated treatments were greater than those of the control treatment in all of the regions. The Bavi region had the highest Cd (14.29 in soil; 11.9 in Dill) and Pb (40.46 in soil; 35.53 in Coriander) and the lowest Zn (34.75 in soil ; 28.44 in Carrot) and Cu(22.30 in soil; 16.96 in Carrot) concentration values in both soil and plants subjected to kerosene contaminated treatments. Also, the lowest concentration values of Cd (9.33 in soil; 8.01 in Carrot) and Pb (30.36 in soil; 23.54 in Carrot) and the highest values of Zn (109.08 in soil; 86.33 in Dill) and Cu (47.71 in soil; 38.57 in Dill) were recorded in Shush and Dezful regions, respectively. Based on these findings, kerosene usage could lead to a significant increase in the heavy metals (Cd, Cu and Pb) uptake, exceeding the critical level for the vegetables. This might increase the transformation risk of the mentioned heavy metals in the food chain
F. Farsadnia, B. Ghahreman, R. Modarres, A. Moghaddam Nia,
Volume 22, Issue 3 (Fall 2018)
Abstract
In recent years, the joint distribution properties of drought including severity and duration have been widely evaluated using copula. Few studies, however, have worked on drought modeling based on stream flow, especially in semi-arid regions such as the southern regions of Iran. This study followed two purposes. The first purpose was to find the appropriate marginal distribution function for hydrologic drought duration and severity, and the other one was to find appropriate copulas. First, the severity and duration of hydrological droughts in the hydrometery stations in the Karkhe basin were extracted by the run’s theorem, and the absence of trends was tested using the modified Mann-Kendall trend test. Appropriate marginal distribution functions for duration and severity drought were derived by using the linear moment's method. In addition, copula’s parameters for Frank, Clyton and Gumbel families were calculated by both direct and indirect methods. The best copulas were selected by the goodness of fit tests. Finally, the joint and conditional return periods for duration and severity drought were derived for each station. The results showed that drought severity and duration for all hydrometery stations in Karkhe basin followed both the generalized extreme value marginal distribution function and Gumbel copulas family, which could be used for regional copulas modeling.
S. Ghobadi Alamdari, A. Asghari Moghaddam, A. Shahsavari,
Volume 23, Issue 4 (Special Issue of Flood and Soil Erosion, Winter 2019)
Abstract
Lack of the proper conjunctive use of surface and groundwater resources causes large water stresses in one of these resources. Conjunctive use of surface and groundwater, especially in arid and semi-arid regions, is a scientific and practical solution for sustainable water resources management. The aim of this research was to prepare some mathematical modeling to apply the conjunctive use of surface and groundwater in the Dehloran plain aquifer. In this study, the mathematical model of the Dehloran plain aquifer was developed using GMS 9.1 and the river data were entered. For the steady state condition, the time series data in the average year 2010-2011 were utilized. In the next step, the time series data from October, 2010, to September, 2011, were used for the unsteady state analysis. In the unsteady state, four stress periods were taken; then the model calibration was carried out in three steps for each stress period; after the optimization of the hydrogeological parameters of the model, its verification was done for the period of 2011-2012 period. After the calibration of the model in the unsteady state, the values of the mean error (ME), the mean absolute error (MAE) and the root mean squared (RMS) errors measured in piezometers were obtained to be -0.24, 0.46 and 0.65, respectively. The results of verification confirmed the ability of the model in simulating the natural conditions of the aquifer. Finally, applying different scenarios to the model showed that the proper conjunctive use of surface and groundwater could increase the volume of water at a rate of 2.23 million cubic meters per year.
V. Habibi Arbatani, M. Akbari, Z. Moghaddam, A.m. Bayat,
Volume 26, Issue 4 (Winiter 2022)
Abstract
In recent years, indirect methods such as remote sensing and data mining have been used to estimate soil salinity. In this research, the electrical conductivity of 94 soil samples from 0 to 100 cm was measured using the Hypercube technique in the Saveh plain. 23 types of input data were used in the form of topographic and spectral categories. Land area parameters such as the Topographic Wetness Index (TWI), Terrain Classification Index (TCI), Stream Power Index (STP), Digital Elevation Model (DEM), and Length of Slope (LS) were considered as topographic inputs using Arc-GIS and SAGA software. Also, salinity spatial and vegetation indices were extracted from Landsat 8 images and were considered spectral inputs. The GMDH neural network was used to model salinity with a ratio of 70% for training and 30% for validation. The results showed that the soil salinity values were between 0.1 and 18 with mean and standard deviation of 5 and 4.7 dS/m, respectively. Also, the results of modeling indicated that the statistical parameters R2, MBE, and NRMSE in the training step were 0.80, 0.06, and 42.1%, respectively. The same values in the validation step were 0.79, 0.13, and 48.7%, respectively. Therefore, the application of spectral, topographic, and GMDH neural network indices for modeling soil salinity is effective.