The large variation of rainfall from one year to another, it's variable distribution and delayed fall's effective rain, are the weather characteristics of rainfed farming area in Maragheh.In such condition a proper scheduling for one or two single supplementary irrigation could have produced a significant difference in crop production.In order to study the effects of single irrigation (during planting & flowering stages 50 mm in each) on yield of 4 varieties of wheat (sabalan cross, Anza cross, Azar2 and sabalan), an experiment was conducted during 1996-1998 in Maragheh station.The amount of rainfall was 351 and 202 mm respectively. Irrigation system was adjustable sprinkler. All wheat varieties showed positive reaction to single irrigation in planting time, but Azar-2 and sabalan cross wheat varieties showed the most in both years with about 1000kg.ha-1 yield increase to a total of2.5 ton. Ha-1. Since Azar -2 had high yield increase in both single irrigation management in planting and flowering stages, it was recommended as the favorable variety.

This study investigated the effect of sowing date and limited water allocation management for single irrigation on the grain yield of rainfed barley. The experiment was a split-split plot arranged in a randomized complete block design with three replications from 2004 to 2006 at the main station of the Dryland Agricultural Research Institute at Maragheh. The treatments comprised three sowing dates (early, normal, late) and Yesevi-93 (Abidar), and Dayton (URB79-7) barley varieties. The single irrigation allocations tested were rainfed, planting time irrigation (50 mm and 100 mm), and spring irrigation (50% and 100% depletion of available water). Grain, straw and biomass yields were measured. Barley production function was estimated for total water used (sum of precipitation and irrigation water). Generally, there was a linear function between water use and yield and the effectiveness of the amount and time water allocation was evident. Results showed that single irrigation at planting time and limited single irrigation (50% depletion of available water at root zone) at spring time (during heading to flowering stage) had significant effects on yield and water use efficiency. The average grain yield for single irrigation at planting time (3794 kg.ha-1) was about 300% more than the average for rainfed (1170 kg.ha-1). Single irrigation at planting time caused early crop establishment for autumn and relatively early maturity, which reduced the growing period. The grain yield for spring single irrigation was about 1000 kg.ha-1 more than the average rainfed condition. Spring single irrigation improved soil water content and increased yield and yield components (especially thousand kernel wt.). Thus, wheat production can be substantially and consistently increased under cooperative management of limited single irrigation and agronomic management.

To investigate the relationship between grain yield and its components in spring rapeseed crop farming, this study was conducted as split plot arranged in a randomized complete block design (RCBD) with two factors and three replications and two years on spring canola varieties in Maragheh Rainfed Agricultural Research Station. The treatments were four levels of single irrigation amounts (Zero, 30, 60 and 90mm irrigation water use) at growth stages (stem elongation, flowering and seed filling stage). There were positive significant correlations due to grain yield with all agronomic characters. Under single irrigation, path analysis and determination of direct and indirect effects showed that, number of pods per square meter, straw yield and seed number per pod has a direct positive effect and thousand seed weight has a negative direct effect on grain yield. Optimum level of single irrigation for rapeseed was 60mm irrigation at flowering stage that lead to producing 1071kg grain per hectare due to control of soil moisture stress at flowering stage. This treatment affected on grain yield (83% compared to rainfed condition) by increasing growth and produce new pods.

In order to investigate the effects of single irrigation treatments on bread rainfed wheat (Triticum aestivum L.) a field experiment was conducted as split block arranged in a randomized complete block design (RCBD) with three replications in 1997-99 at Dryland Agricultural Research Institute (Maragheh Station). Total seasonal rainfalls were 351 and 210 mm, respectively. The treatments included three levels of irrigation (rainfed, one time irrigation at planting time (50mm), one time irrigation at flowering stage (50mm» and four rainfed wheat varieties (Cross Sabalan (V1), Cross Anza (V2), Azar2 (V3) and Sabalan (V4). The 1997-98 season was normal, while in 1998-99 the rainfall amount and its distribution was not suitable. Results showed that the single irrigation was effective in increasing yield. Irrigation at planting time caused early germination and increased 500-900kg.ha-1 grain yield. Grain, straw yields, height and TKW were determined from the middle of each plot and biological yield and harvest index were calculated There were positive significant correlations between grain yield with other yield components except TKW. Results of path analysis showed that increase in grain yield was due to increase seed number per spike, spike number per square meter and TKW respectively. Optimum level of single irrigation was at planting time combined with Azar2 wheat variety obtained maximum water use efficiency (19 which kg.mm-1) and maximum yield. Thus, when limited water use is combined with appropriate management, grain wheat production can be substantially and consistently increased in this semi arid zone. Single irrigation at planting time is useful when total costs of water and irrigation are 2095 Rial.m-3 water.

Abstract LST (land surface temperature) derived from thermal infrared remote sensing images is directly related to land use and land cover changes. Remote sensing, as an irreplaceable method to obtain LST at global and regional scales, enables effective monitoring of LST with Spatio-temporal continuity. LST helps in separating urban areas from bare areas and improves land use/cover generation through classification of remotely sensed imagery. In this study, a Python-based user interface was developed to make land surface temperature retrieval easier and faster. LST can be retrieved by inputting required parameters in different methods such as Single Channel Algorithm (SCA), Radiative Transfer Equation (RTE) method, Split Window Algorithm (SWA), and two Mono Window Algorithms (MWA), from Landsat missions (Landsat 5, 7, and 8). Comparing the results in this study showed that RTE and SCA with root mean square error (RMSE) equal to 3.76 and 8.97 degrees Celsius had the highest and lowest accuracy. LST is affected by atmospheric particulate matter, land cover and urban morphology. Various methods of LST retrieval consider surface temperature, water vapor and other atmospheric factors. The developed user interface helps researchers and managers in monitoring land surface temperature change through time as affected by land use/cover, especially urban land use

Water is an important factor in crop production, and is of a high value in agricultural Engineering. Water shortage is the most restricting factor in irrigated areas. Because of quality and quality limitation, deficit irrigation research has a special value in water use optimization and determination of water depths indexes in irrigation strategy. Thus, a determination of the water-yield relationship is essential. This study was carried out in Gorgan region to evaluate the effects of water stress on yield and water use efficieny of soybean in six levels of irrigation (is1-is6) for Sepideh variety in six replications using line source sprinkler irrigation method. Yield function for was derived as (Y=-0.0528x2+54.907x-3073.5, R2=0.93). Under full iriigation, the sepide cultivar need 354.9 mm of water to produce maximum yield of 10190 kg/ha. Maximum and minimum of water use efficiency were obtaibed 16.0 and 35.3 kg/ha.mm at IS1 and IS4, respectively. Average grain yield and number of pods per plant were increased by increasind water depth. Minimum of grain yield, number of pods per plant and thousand grain weight were obtained in Is1. FAO water stress index (Ky) was obtained 0.94. Ky was derived 0.92. The comparison between the ky of cultivated soybean cultivars at Golestan province showed that katool cultvar has the more suitable response to water deficit than sahar and G3 cultivars to increase yield and optimal use of limited water resources.

Introduction: Two of the main challenges in developing countries are food production and trying to get ahigh income for good nutrition and reduction of poverty. Cereals and legumes are the most important crops inthe rainfed areas of the country occupying the majority of dry land areas. Irrigated production systems had amain role in food production in the past years; but unfortunately, in recent years, with high population andcompetition of industry and environment with agricultural sectors, getting adequate irrigation water is difficult. The main purpose of this study is to determine the best option of crop agronomic management. Rainfedagriculture is important in the world; because this production system establishes %80 of the agriculture area and prepares %70 of the food in the world. In the Lorestan province, production area for rainfed barley is 120, 000 haand the amount produced is 120000 ton (approximately 1009 kg per ha). The purposes of this study were toevaluate cost, benefit and profit of rainfed barley production, economical and non-economical substitution oftreatments in different agronomic management, study of sale return, cost ratio, determining break-even of priceand comparing it with the guaranteed price of barley and estimating the value of water irrigation.Materials and Methods: This research was carried out by sample farmers (12 farmers) on rainfed barley atthe Honam selected site in the Lorestan province during 2005-07. At on-farm areas of the upper Karkheh RiverBasin (KRB) three irrigation levels were analyzed (rainfed, single irrigation at planting time and singleirrigation at spring time) under two agronomic managements (advanced management (AM) and traditionalmanagement (TM). Data was analyzed by Partial Budgeting (PB) technique, Marginal Benefit-Cost Ratio (MBCR), and economical and non-economical test. For estimation of net benefit the following formula was used: N.B=B (w)- c (w) =(YG×PG +YS ×PS)-(C1+Pw×w) Where: N.B: Net income (Rials / ha), B (w): Gross income, C (w): Cost of production, YG: Crop yield (kg/ ha), PG: Price of crop (Rials/kg), YS: straw yield (kg/ ha PS: Price of straw (Rials/kg), C1: Total fixed cost without cost of water and irrigation (Rials/ ha), Pw: Price of water and irrigation (Rials/ m3) and W: Amount of water and irrigation (m3/ ha). Changes of incomes and changes of costs for every treatment in different crop managements were used asfollows: ∆B = B (w) j+1 - B (w) j∆C =C (w) j+1 -C (w) jWhere j and j+1 show existence and substitution crop managements.In order to determine the price of irrigation water, total cost including pump and electromotor, semi deepwell, power instrument, maps, pipe transport and implementation network, other primary cost and operation costwere used. The analysis period for the instruments (pump and electromotor, maps, implementation network) was20 years and for the semi deep well was 30 years. In this study, total cost was referred to the present value with %15 discount rate by uniform series formulas. Then, the water was used in the farm. The price of water wasdetermined. Capital recovery formula is as follows: A = P (i (1+ i) n / (1 + i) n)  1= P (A / P, i, n) Where: A: Annual value of primary investment costs, P: Primary investment costs for irrigation system, i: Discountrate and n: analysis period.Results and Discussion: According to the results, the price of water and irrigation at the research regionbased on its components and under 15% and 25% interest rates were obtained to be 213 and 338.1 Rials percubic meters, respectively. The barley grain yield and its net benefit under advanced management were morethan that obtained under traditional management. In traditional management, the mean barley grain yield for treatments including rainfed, Single irrigation (SI)- planting and SI spring were estimated to be 1572, 2487 and 2670 kgha-1, respectively. The mean profit forrainfed barley production for treatments including rainfed, SI-planting and SI spring were estimated to be 1270.2, 2314.2 and 2607 (Thousand Rial.ha-1), respectively. In advanced management, the mean barley grainyield for treatments including rainfed, Single irrigation (SI) -planting and SI spring were estimated to be 2270, 3444 and 2853 kgha-1, respectively. The mean profit for rainfed barley production for treatments includingrainfed, SI-planting and SI spring were estimated to be 1987, 3465.4 and 2519.8 (Thousand Rial.ha-1), respectively. In the research site, the mean net benefit of rainfed barley under sowing and spring single irrigationand AM, increased by about 173% and 98.4%, respectively.Conclusion: The results showed that the substitution of AM-SI planting treatment instead of other treatmentswas non-economical. On the other hand, in this substitution, decreasing of profit is more than decreasing of cost.Finally, at Honam site, recommended management include: AM+planting SI, AM+spring SI, and rainfed AM, respectively.