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Available online xxxKeywords: Evapotranspiration Growing degree days Spring wheat WUE HUE Neutron probe a b s t r a c t Estimation of actual evapotranspiration (ET a ) is an important part of agricultural water management in local and regional water balance studies. At the field scale, ET a is important in irrigation planning and scheduling and is an integral part of field management decision support tools. The conventional approach of estimating actual evapotranspiration is difficult and needs more calculations and extensive data on soil-plant-atmosphere. A field experiment was conducted to simplify the measurement and calculation of actual evapotranspiration by using thermal units (heat units) for spring wheat crop under trickle irrigation system in sandy soil. Two irrigation methods were applied; the first one (A) using the crop evapotranspiration (ET c ) that depends on whether parameters, and the second (B) is the depletion from field capacity which dependent on soil parameters. Three varieties of wheat namely Sids12, Misr2 and Gemmeza10 were cultivated on sand soil and treatments arranged in complete randomized block design with three replicates. Application of treatment (B) resulted in highly significant increase in yield production of Gemmeza10 and Misr2 as compared to treatment (A). Grain yield of different wheat varieties grown under treatment (B) could be ranked in the following descending order: Misr2 > Gemmeza10 > Sids12. While under treatment (A) it could be arranged in the following descending order: Misr2 > Sids12 > Gemmeza10. On the other hand, the overall means indicated non-significant difference between all wheat verities. The highest values of water and irrigation use efficiency as well as heat use efficiency were obtained with treatment (B). The equation used in the present study is available to estimate ET a under arid climate with drip irrigation system. journal h omepage: http :/ / www .e lsev ie r. co m/ lo cate/ j rras 1

Background: Fenton (Fe 2+ and H 2 O 2) and modified Fenton (Fe 3+ and H 2 O 2) are two popular methods used in advanced oxidation processes (AOP) and degradation of persistent organic pollutants (POPs), such as dye compounds. In these processes, Fe 2+ and Fe 3+ as catalysts and H 2 O 2 as the oxidizing agent are added to the reactor. Objectives: The aim of the current study is to assess the abovementioned methods for removal of Reactive Red 198 and Blue Reactive 19 from aqueous solutions. Materials and Methods: This research was carried out using lab-scale. After preparation of RB-19 and RR-198 stock solutions (1000 ppm), optimum pH and temperature were determined within the range of (3-11) and (15°C-40°C) respectively, and specific amounts of Fe 2+ and Fe 3+ (0.8, 1, 3, 7, 14 and 32 mM) were prepared by adding FeSo 4. 7H 2 O and FeCl 3 , and H 2 O 2 30% W/W (2, 5, 11, 23, 47 and 94 mM) were added to the solutions to establish the H 2 O 2 /Fe 2+ , Fe 3+ molar ratios. Standard jar tests were conducted using jar test apparatus. After sedimentation time, samples were filtered through a 0.45 µm fiber membrane, and then final dye concentrations were measured using a UV/VIS spectrophotometer. Results: The highest dye removal efficiency in both Fenton and modified Fenton methods were obtained at the optimum pH = 3, optimum reaction time of 10 minutes, optimum temperature at 25°C and H 2 O 2 /Fe 2+ and H 2 O 2 /Fe 3+ concentrations of 11.3 and 5.1 mM, respectively. In the Fenton reaction the maximum efficiency was obtained at 94.70% and 99.31% for reactive red 198 and reactive blue 19, respectively. Moreover, by the modified Fenton method the maximum removal efficiency for reactive red 198 and reactive blue 19 was 94.8% and 99.43%. Conclusions: Fenton and modified Fenton processes could be used as very effective methods for removal of reactive red 198 and blue reactive 19 from aqueous solutions.

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