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M. Javahery-Tehrani, S. F. Mousavi, Kh. Hosseini,
Volume 20, Issue 77 (11-2016)
Abstract

Morphologic study of rivers is very important in stabilization and determination of river boundaries. Dams are structures which have the highest effects on river morphology. Studies of river changes are usually time-consuming and possible only in the long-term timescales. To detect these changes, using satellite images over specific time periods and cartographic methods are useful. In the present study, morphological changes of Zayandehrud River, at downstream of Zayandehrud dam, between hydrometric stations of Sad-e-Tanzimi and Pol-e-Zamankhan, were investigated through 7 series of Landsat satellite photos from 1980 to 2015 by applying ENVI 4.8 and Arc GIS10.2 software. Based on the results, the method of enhancing the contrast as saturated linear expansion, along with the edge enhancement filter, was found an appropriate method for determining the boundary between land and water. In the next step, the river path was entered into Arc GIS 10.2, and geometric parameters of the river such as wavelength, sinuosity ratio, central angle and radius of circle tangent to the curve were determined. Also, statistical analysis of geometric parameters was performed by applying SPSS software. Results showed that from 1986 up to now the sinuosity ratio has risen from 2.14 to 2.38, while the radius of river curvatures and wavelength of meanders have decreased by 5% and 11.4%, respectively. Overall, the river has decreased its arcs’ curvature and bends have been moved to downstream. The main cause of this phenomenon is constructions in the river borders (e.g. in Markadeh and Cham-Kaka), which have disturbed the natural situation of the river. In Cham-Jangal, Cham-Khalifeh and Cham-Ali regions, due to the increase in slope and improper vegetation cover, bank erosion has reached to its highest degree. In general, although flood events have been contained by Zayandehrud dam, yet the river has great potential for erosion in the meandering sections.


S. Youneszadeh Jalili, M. Kamali, P. Daneshkar Arasteh,
Volume 20, Issue 78 (1-2017)
Abstract

Integrated management of watershed basins depends on deep knowledge of basic concepts such as the arrangement of lands and their uses. Location and distribution of agricultural land use help to balance water resources in the watershed basins. In this research with the help of satellite images of Landsat 5 and 8, and the method of maximum likelihood classification algorithm, land use types of water, barren areas and salt lands, and irrigated agriculture were studied in the Urmia watershed in the years 2010 and 2013.Then applications of modis images and product Urmia watershed land cover for years 2010 and 2012 were compared and finally modis and Landsat land covers in 2010 were compared. Results showed that the area of irrigated farmlands of Urmia basin has increased in the years between 2010 and 2013; while, the water zone has declined. Comparison between modis and landsat in 2010 showed that modis can estimate irrigated lands and water zone better than barren areas. The kappa coefficient for years 2010 and 2013 in Landsat images are 0/77 and 0/87, respectively.


A Heidari, H. Haji Agha Alizadeh, A. R. Yazdanpanah, J. Amiri Parian,
Volume 20, Issue 78 (1-2017)
Abstract

Traditionally, most corn field in Hamedan Province is prepared for planting by moldboard plowing followed by a number of secondary tillage operations. In recent years conservation tillage systems have become more popular. This research was conducted in the form of a split plot experimental design with six tillage treatments and three replications. Main tillage methods including: (T1) conventional tillage (moldboard plow + cyclotiller equipped with roller), (T2) combination tiller (chisel plow equipped with roller) (T3) bandary tillage with chisel blades were considered as main plots and two P fertilizer application including: (F1) fertilize broadcasting and (F2) fertilizer bandary placement were considered as sub plots. During growing seasons, soil mechanical resistance (cone index), soil bulk density and water infiltration in soil were measured. At the end of the growing season (harvesting time), corn yield and its components were measured. Results indicated that tillage methods and soil depth had a significant effect on the soil bulk density and cone index. The effect of tillage on water infiltration in soil was significant. The effect of P fertilizer application on corn yield was significant (P≤0/01) and P fertilizer bandary placement with mean corn yield of 10862 kg/ha had higher yield value than the fertilizer broadcasting with mean corn yield of 9965 kg/ha. Although the difference between tillage methods for corn yield was not statistically different, T2 treatment with mean corn yield of 10913 kg/ha had higher yield value than the other two tillage treatments (T1 with mean corn yield of 10106 kg/ha and T3 with mean corn yield of 10222 kg/ha).


K. , and M. R. Nosrati, M. Amini, A. Haddadchi, Zare3,
Volume 20, Issue 78 (1-2017)
Abstract

Accelerated soil erosion in Iran causes on-site and off-site effects and identifying of sediment sources and determination of their contribution in sediment yield is necessary for effective sediment control strategies in river basin. In spite of increasing sediment fingerprinting studies uncertainty associated with magnetic susceptibility properties has not been fully incorporated in models yet. The objective of this study is determination of the relative contribution of sediment sources using magnetic susceptibility properties (High frequency, Low frequency and Frequency dependence) incorporated in uncertainty mixing model. For this purpose, 25 bed sediment samples were collected from the outlet of drainage basin and outlet of sub-basins and their magnetic susceptibility was measured and calculated. The results of Kruskal–Wallis test and discriminant function analysis showed that magnetic susceptibility properties can be used as optimum set of tracers in the uncertainty mixing model. The results of Bayesian mixing model indicated that mean (uncertainty range) relative contribution of Sparan, Joyband and Boyoukchay are 92 (83.9-94.8), 2.8 (0.2-10.7), 5.7 (0.2- 10.5) percent, respectively. According to these results, the highest amount of sediment yield is related to Sparan sub-basin and these results could be used in soil conservation and management planning.


M. Nadi, A. Golchin, E. Sedaghati, S. Shafie, S. J. Hosseini Fard, G. Füleky,
Volume 21, Issue 1 (6-2017)
Abstract

Soil organic matter is the largest source of organic carbon in the soil surface which played an enormous role in restoring balance, environmental sustainability, soil elements and climatic conditions. Organic materials influence physical, chemical and biological properties of soil and thus soil fertility directly and indirectly. The amount, type and composition of organic matter are different in different soil and climatic conditions. Different soil components can hold different combination of soil organic matter. In this study soil samples were collected from virgin, Populus and Alnus forests from Guilan Province, Iran. The amount of organic matter in the original samples and sand, silt and clay fractions were measured and the quality of organic carbon (13C) and hydrogen (1H) were determined in fractions by Nuclear Magnetic Resonance. Based on the results the amount of organic carbon in the original samples of Alnus forest was highest. among fractions, clay had the highest amount of organic carbon. The result of Nuclear Magnetic Resonance showed presence of different aliphatic and aromatic carbons and hydrogen in different samples. Virgin forest had the highest proportion of alkyl to oxygenated alkyl carbon ratio and Alnus forest showed the highest ratio of aliphatic to aromatic carbon,. Both mentioned ratios was higher in clay fraction than other two fractions.


M. Shamsalddin Saied, A. Ghanbari, M. Ramroudi, A. Khezri,
Volume 21, Issue 1 (6-2017)
Abstract

Cover crops, conservation tillage systems and organic fertilizers have played an important role in maintaining or enhancing soil quality. In order to assess the combined effects of these techniques on soil quality an experiment was conducted as split Plot experiment based on randomized complete block design with three replications at Shahid Bahonar University of Kerman in 2011-2012.
     The method of return of cover crops to soil included reduced tillage (disc) and no-till (herbicide glyphosate + cutting) as the main factor and manure application management included cover crops (wheat, canola and peas) without the use of urea, cover crops with a consumption of 25 t/ha of manure, Cover crop with 75 kg of urea and fallow treatments (without cover crop) as subplots. The results showed that the highest concentration of nutrients (except N and P concentrations in the plant), the nutrient yield and biomass of cover crops belonged to wheat treated with urea fertilizer. Soil properties such as bulk density, pH, organic matter and soil nutrient concentrations (nitrogen, phosphorus and potassium) were significantly affected by fertilizer management and the method of return of cover crops to soil (except pH) and soil organic matter content and nutrient concentration were affected by their interactions. In wheat cover crop treatments with urea with %27.53 reduction in bulk density, %20.88 increase in the porosity, organic matter 2.4 times and nitrogen 1.5 times compared to the fallow treatment was the best treatment that wasn’t significantly different from the wheat treated with manure in low- tillage system. Wheat treated by manure had the highest phosphorus that was 3.5 times of the phosphorus concentration in the fallow treatment. So, in order to develop sustainable agriculture, reducing the use of synthetic fertilizers and environmental protection, the wheat cover crop treatments with manure and low- tillage cropping systems would be appropriate in Kerman.

Z. Sepehri, Z. Jafarian, A. Kavian, Gh. Heydari,
Volume 21, Issue 1 (6-2017)
Abstract

Ash and coal produced from fire influence the soil and few studies about these effects are available. For this purpose, this study was performed to investigate the effect of ash and coal on hydrological, physical and chemical properties of soil in Charat rangeland that has a history of fire. Systematic-random sampling was implemented in two plant types Astragalus gossypinus and Artemisia aucheri using 6 transects and 60 4m2 quadrates and plant and soil samples were obtained. Experimental treatments including control soil, composition soil and ash were prepared manually and also with artificial rain, composition soil and coal manually and also with artificial rain in the laboratory and characteristics of the texture, saturation moisture, pH, organic matter, field capacity, wilting point, available water and retention capacity were measured. ANOVA results for mean comparison soil, ash and coal properties showed that ash had more percent of silt and pH than soil and organic matter and lower bulk density than soil. In addition, multivariate analysis to show the effect of two types of treatments showed that manual composition of ash and coal with soil had increased field capacity and available water while composition of soil and coal with artificial rain had no significant effect on them. According to the results of this study, the presence of ash and coal resulted from burning vegetation caused great changes in soil properties, especially water retention.
 

Seyyed S. M. A. Maddahzadeh., K, Esmaili, B. Ghahraman,
Volume 21, Issue 1 (6-2017)
Abstract

Bi-level drainage system is a type of underground drainage systems, in which adjacent drainage lines are installed at different depths. In the Hydraulics Laboratory, Ferdowsi University of Mashhad, a model was built, that include a cube tank 2 meters in length, width and height of 1 meters was made ​​of galvanized. In this model, two rows 20 cm apart from each other drains were installed. As drainage, a pipe of three layers to the outer diameter of 16 mm was made of PVC. Within this model of stratified soil was used as a soil layer of low permeability with a hydraulic conductivity of 1.15 cm per hour, thickness of 20 cm soil layer between two light soil layer with 30-cm thickness for bottom layer and 20 cm for the top layer with a hydraulic conductivity of 1.55 cm per hour. For accurate measurement of the water table Behavior in the soil at each point of the model, some piezometer distance of 10 cm from each other on the floor model was installed. After Outfit of model with blow-off valve, Experiments with a heavy irrigation for different intervals between depths of 30 and 50 cm were used in drainage and water table elevation values ​​as observed values ​​were extracted from the model. The results show that the values ​​obtained from Upadhyaya and Chauhan Equation only in small area of water table profiles, which include an area of between the two drainage, are consistent with observed and with a wider distance between deep and shallow drainage, time of drop in water table increased.


H. Khaledian, D. Nikkami,
Volume 21, Issue 1 (6-2017)
Abstract

Appropriate utilization of agricultural land and natural resources, decreased erosion and increased production occurs in watersheds. On the other hand, land use pattern due to increasing human activities on the ground to meet different needs, is changing. Optimization of land use is one of the management methods to achieve stability and reduce soil erosion. In this study, by using linear programming (simplex) and Geographic Information System(GIS), was investigated the land use optimization in three scenario option to: current condition, management condition, and standard condition.Erosion potential by using MPSIAC Model in irrigated land 1.65, dry lands 3.31, pasture 3.64, gardens 1.49 and 3.85 tons per hectare per year was estimated for Chehel-Gazi basin. The results of the sensitivity analysis for tree scenario showed that in the event optimize land use, erosion potential in the current Condition 0.85 percent increased, But in the land management Condition 16.92 percent and in a standard Condition 32 percent decreased. The results of sensitivity analysis showed that changes in the area of pasture all three options have the greatest impact in changing erosion potential of basin.


Sh. Ghorbani Dashtaki, N. Karimian, F. Raeisi,
Volume 21, Issue 1 (6-2017)
Abstract

The use of organic matter such as urban sewage sludge may help sustainable soil fertility via improving the physical, chemical and biological soil characteristics. The main purpose of this study was to determine the effect of urban sewage sludge on chemical properties, soil basal respiration and microbial biomass carbon in a calcareous soil with silty clay loam texture. Therefore, three levels of water repellency (zero, weak and strong) were artificially created in a silty clay loam soil by adding urban sewage sludge (S0=0:100; S50=50:50 and S80=80:20 sludge weight: soil ratio). Water repellency was determined by water drop penetration time (WDPT) method. Also some chemical properties such as soil acidity (pH) and Electrical Conductivity (EC), Soil Organic Carbon (OC), soluble sodium (Na+) and soluble potassium (K+) were measured. The samples were incubated at 23-25 ºC for 30 days and their moisture was maintained at 70-80 % under field capacity and soil basal respiration and microbial biomass carbon of incubation period were evaluated. The results showed that the effect of urban sewage sludge on chemical properties was significant (P ≤0.0001). The application of urban sewage sludge led to significant increase in basal respiration (16 and 27 times) and microbial biomass carbon (15.2 and 26.5 times) in the water repellency soils (S50 and S80) compared to control soil. The observed positive effect of sewage sludge might be due to a high content of organic carbon and nutrients in urban sewage sludge and decrease in the labile organic matter and nutrients during incubation period.
 
 


H. Saghi,
Volume 21, Issue 1 (6-2017)
Abstract

The water supply networks have always been of significance to researchers as a hydraulic system of transferring and distributing water. The pressure gradient is the main reason of water transfer in networks, and in case of non-standard pressure increase, the undesirable phenomenon of leakage occurs in the network. Leakage in urban water distribution networks causes water waste and enormous financial losses. Therefore, there exists the need to manage and minimize the amount of leakage. In this study, a water distribution network is modeled using the potentialities of hydraulic analysis model, the EPANET 2.0, and, by presenting a new model, the leakage location is recognized. In order to do this, we, firstly, entered all the network parameters into the software. Then, the network was analyzed supposing the non-occurrence of leakage and the amounts of nodal pressures were measured. Moreover, the nodal pressures were estimated by creating a hypothetical leakage in one of the network nodes and analyzing the network. Finally, the position of leakage was determined by defining the leakage index and comparing it in various nodes. The results show that the suggested method is efficiently capable of predicting the leakage position in the network so it can safely replace other methods, especially destructive methods used in recognizing the leakage position in the network.

A. Morshedi, M. Naderi, S. H. Tabatabaei, J. Mohammadi,
Volume 21, Issue 2 (8-2017)
Abstract

Conventional methods for estimating evapotranspiration are based on point measurement and suitable for local areas, therefore, cannot be generalized for larger areas or watershed basins. The remote sensing technology is capable of using satellite images and meteorological data to estimate evapotranspiration in a wider area. In this study, estimates of evapotranspiration (ET) by SEBAL and METRIC models based on Landsat 7 ETM+ sensor were compared against ET measured by lysimeter on seven satellites passing time over Shahrekord plain located in Karun basin. The results showed that the lowest indices of NRMSE, MAE and MBE (respectively, 0.317, 1.503 and -0.973 mm per day) and the maximum of d index (0.768) belonged to SEBAL. These indices were 0.420, 2.120, 2.023 and 0.646 for METRIC, respectively. The results showed that the SEBAL was more accurate than METRIC model for estimating ET under Shahrekord plain conditions. As long as the possibility of getting complete hourly meteorological data be provided, or some modifications on METRIC model were done, SEBAL show closer results to reality, and therefore is recommended.
 


S. Moradnia, R. Naderi, M. Najafi,
Volume 21, Issue 2 (8-2017)
Abstract

In order to investigate the persistence of organic amendments, nitrogen and zinc effects on soil characteristics in rapeseed-wheat rotation, a factor analysis was conducted in a complete random design with three replications in two consecutive years in a greenhouse. Treatments in the first year consisted of N fertilizer, municipal waste compost, vermicompost, sheep manure. The control consisted of zinc and two rapeseed cultivars. In the second year of the experiment, two cultivars of durum wheat were sown in the same pots as the first year of the experiment. Results showed that two years after application of cattle manure, a significant increase in soil electrical conductivity (41.81 %), available K (59.45 %) and available Mn (79.82 %) compared to the control were found.  Saturated soil moisture (48.57%), total N (94.66 %), available Fe (46.49 %) and available Cu (47.51 %) significantly increased by municipal waste compost compared to the control. Also, Zinc had a significant effect on soil total N (0.28 %), available K (218.4 mg/kg) and available Mn (12.89 mg/kg). Generally, the results showed that application of organic amendments can change many soil characteristics which some of their impacts might last for next upcoming years. Therefore, it is necessary to monitor the soil characteristics and nutrients availability of the fields that were treated with organic amendments in the years after application.
 


A.r. Keshtkar, Sh. Mohammadkhan, R. Houshmandi, S. Dalfardi,
Volume 21, Issue 3 (11-2017)
Abstract

Recently, catchments were considered as planning and management units for sustainable development in many issues. Catchment sources management is considered as a new principle for development planning and management of water and soil resources emphasizing on socio-economic characteristics of the region to sustainable livelihoods and without vulnerability of plant and the residents of an area. These objectives will be achieved when the proper management of resources and the management should be applied to decrease destructive processes and strengthen the improvement processes. Aiming at biological management of watershed resources with scenario building approach, this study has assessed and prioritized biological management options in the Delichay Catchment. With a choice of four biological management activities, 16 scenarios were developed in the study area. Then, criteria weighting was carried out using analytic hierarchy process and ultimately, the best management option was chosen using TOPSIS model. The results indicated that social, ecological, economic and physical criteria were respectively prioritized from one to four and scenario number 10 was determined as the best scenario and the first priority. Also, the results showed that the multi-criteria decision making techniques included capability of expressing different aspects of the problem and are perfect tools for integrated watershed resources management.
 


A. Ghasemi, A. Ghanbari, B. A. Fakheri, H. Fanaie,
Volume 21, Issue 3 (11-2017)
Abstract

In line with sustainable agriculture development, an experiment was conducted including tillage as the main factor in two conventional systems (plowing and mixing fertilizer with soil) and no tillage (leaving residuals of green manure and direct corn sowing). The fertilizer resources were T0: control, T1: barley green manure without chemical and manure fertilizers, T2: barley green manure with full use of the recommended chemical fertilizer (NPK) to barley containing urea, super triple phosphate and potassium sulphate respectively as 165, 90, and 75 kg/ ha, T3: green manure with two -third residual of chemical fertilizer for barley and a third of the residual to corn, T4: green manure with one- third chemical fertilizer for barley and two-third for corn, T5: barley green manure mixed with 50% manure and 50% chemical fertilizer, and T6: green manure with 40 tons of manure used as a sub-plot in the split plot and in completely random blocks with three replications for two crop years ( 2013-2014) at the Agricultural Research Station, Sistan. The results showed that in comparison with no-tillage, the conventional tillage resulted in a significant increase in grain yield, the contents of nitrogen, phosphorus, potassium and soil organic carbon, bulk density and moisture content of the soil decreased in the conventional tillage. Sources of fertilizer (organic and chemical fertilizers) significantly increased soil organic carbon, nitrogen, phosphorus, potassium, and soil moisture content. The pH and soil bulk density factors decreased after using manure sources. Interaction tillage in the fertilizer sources showed that in the conventional tillage and Treatment T5 (mixture of manure, green and chemical fertilizers) the highest yield of corn was obtained with an average of 8471 kg/ha. The results of this experiment reported that using conventional tillage system with mixture of 50% manure, green and chemical fertilizers can increase corn grain yield, provide the dynamics of nitrogen, phosphorus, potassium, organic carbon, and improve soil bulk density and soil pH.
 


M. Golabi, M. Albaji, A. Naseri,
Volume 21, Issue 3 (11-2017)
Abstract

In the present study Hydrus-1D software was used to simulate electrical conductivity, pH and sodium, potassium, calcium, magnesium, chloride and sulfate ions. Field experiments were performed at the Sugarcane Research Center located in south of Ahvaz on sugarcane varieties CP48-103 with four water treatments (one treatment was Karun river water and three treatments were diluted drainage water) and three replications. The samples were collected from 0-30, 30-60 and 60-90 cm soil depth before irrigation and electrical conductivity and anions and cations of soil were measured in the laboratory. Sensitivity analysis and calibration were first performed with the aim of verifying the Hydrus-1D software. The sensitivity analysis indicated that the software had maximum sensitivity to the saturated volumetric water content. Minimum sensitivity was for the inverse of the air-entry suction, tortuosity parameter, residual volumetric water contents and moderate sensitivity was for hydraulic conductivity at natural saturation. Also, the software did not show any sensitivity to empirical parameter related to the pore size distribution that is reflected in the slope of water retention curve. In calibration stage the amount of hydraulic conductivity at natural saturation, residual volumetric water contents, saturation volumetric water contents, the inverse of the air-entry suction, empirical parameter related to the pore size distribution and tortuosity were obtained as 18 (cm/day), 0.04 (cm3/cm3), 0.63(cm3/cm3), 0.012 (cm-1), 1.2 and 0.6 respectively. The results showed that the coefficient of determination of all parameters was more than 0.85 which confirms the appropriate capabilities of the model in simulation of electrical conductivity, pH, anions and cations. In the modeling carried out the amount of NRMSE was between 11 and 18 percent which indicates good performance of the model. The Nash-Sutcliffe efficiency criterion was obtained 0.72 to 0.8 that indicates a good match of the model with reality. The coefficient of residual mass in this paper was positive for electrical conductivity, pH and sodium, potassium, calcium, magnesium and negative for chloride and sulfate. The positive and negative coefficient of the residual mass shows less and over estimation of the model.
 


A. R. Keshtkar, H. Shariatmadari, H. R. Naseri, M. Tazeh,
Volume 21, Issue 4 (2-2018)
Abstract

Nowadays, inappropriate land use and degradation of natural resources have led to increase of flood, soil erosion etc. In such critical conditions, an integrated planning in natural resource management with the goal of control, reclamation and conservation seems to be necessary and these kinds of purposes can be reached by an integrated watershed management. Comprehensive management of watersheds is a coordinated and harmonic management of physical, biological, social and economic systems, which provides conditions that minimize the negative impact on resources while safeguarding the interests of the community. In this research, in line with the goals of resource management, the impacts and consequences of physical, economic and ecological criteria on vegetation condition changes were evaluated with focus on elimination of flood and soil erosion issues in Nahrein watershed (with the area of 18800 ha located in Tabas). The evaluation was done by considering four management activities: management of grazing, planting, seeding, and sowing. The prioritization of the scenarios was carried out using analytical hierarchy process (AHP) technique. Then, based on the suggestions and comments from relevant experts, the evaluation of available options was done by pairwise comparison matrix method. After calculations, economic criteria was selected as the most important criteria and management activity of sowing and scenario No. 16 were introduced as the most appropriate reform plan and scenario for the study area which is selected based on available criteria

R. Amirnia, J. Jalilian, E. Gholinezhad, S. Abaszadeh,
Volume 21, Issue 4 (2-2018)
Abstract

To evaluate the effect of supplemental irrigation and seed priming on yield and some quantity and quality characteristics of vetch (Vicia dasycarpa) rainfed maragheh cultivar, an experiment was carried out at the Research Farm of Faculty of Agriculture, University of Urmia, West Azarbaijan province, Iran, during 2011. The experiment was laid out using split-plot, based on Randomized Complete Block design in three replicates. The factors studied were: Supplemental irrigation at four levels: without supplemental irrigation (I1), 1 time of supplemental irrigation (I2), 2 times of supplemental irrigation (I3) and 3 times of supplemental irrigation (I3). The subplot included four levels of seed priming: Control (C), Water (W), Phosphate (P) and Nitroxin (N). Plant height, pod number in stems, 1000-grain weight, wet and dry forage yield in the second and third harvest and fiber percentage in the second and third harvest, protein yield in the second and third harvest, biological yield and harvest index were influenced by the supplemental irrigation. Wet and dry forage yield in the second harvest and wet forage yield in the third harvest were highest in I4 with respectively 14.5, 16.72 and 3.56 (tons/hectare) yield and lowest with respectively 7.73, 7.47 and 2.06 (tons/hectare) yield. As a result, applying 2 times of supplemental irrigation and seed treatment with phosphate and nitroxin had positive effects on quality and quantity yield of vetch and they could improve the quantity and quality of Vetch forage.
 


A. Honarbakhsh, M. Pajoohesh, M. Zangiabadi, M. Heydari,
Volume 21, Issue 4 (2-2018)
Abstract

Nowadays, human interferences in the natural resources cause the loss of these resources and lead to destructive floods, soil erosion and other various environmental, economic and social damages. Furthermore, increasing growth of population and climate change intensify the destructions. Thus management and planning through land use optimization is essential for the proper utilization, protection and revival of these resources. The purpose of this study is to couple the fuzzy goal programming and multi objective land allocation optimization approaches to develop a model for watershed management and planning in Chelgerd watershed. The proposed model is based on optimum area determination in various land uses and also their optimum local situation. In this research, a fuzzy model has been proposed. In this model, minimizing the amount of soil erosion and maximizing the amount of profit are priorities, respectively. Moreover, production resources including water and land as well as economic and social problems are limitations of the mentioned model. Results obtained show that the proposed model is an efficient model in land use optimization and sustainable area development and can increase profit to 37% and decrease sedimentation to 2.4%, respectively.

R. Mostafazadeh, Sh. Mirzaei, P. Nadiri,
Volume 21, Issue 4 (2-2018)
Abstract

The SCS-CN developed by the USDA Soil Conservation Service is a widely used technique for estimation of direct runoff from rainfall events. The watershed CN represents the hydrological response of watershed as an indicator of watershed potential runoff generation. The aim of this research is determining the CN from recorded rainfall-runoff events in different seasons and analyzing its relationship with rainfall components in the Jafarabad Watershed, Golestan Province. The CN values of 43 simultaneous storm events were determined using SCS-CN model and the available storm events of each season have been separated and the significant differences of CN values were analyzed using ANOVA method. The Triple Diagram Models provided by Surfer software were used to analyze the relationships of CNs and rainfall components. Results showed that the mean values of CN were 60 for summer and winter seasons and the CN values in the spring and autumn seasons were 50 and 65, respectively. The inter-relationships of CN amounts and rainfall characteristic showed that the high values of CNs were related to high rainfall intensities (>10 mm/hr) and rain-storms with total rainfall more than 40 mm. Also the CN values were about >70 for the storm events with 40-80% runoff coefficient values.


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