The improvement of saline and sodic soils aims to reduce the dissolved salts in the soil solution. In this context, an integrated management approach is required, which not only improves its effectiveness in improving soil properties but also increases water productivity and yields. To mitigate the negative effects of soil salinity, improvement of soil properties and yield –water productivity of rice plant, a field trial was carried out at El-Hamoul region, Kafer El-Sheikh, Egypt, during the summer seasons of 2019 and 2020. The experiments were conducted in split plot design, with three replicates. The main plots were assigned to soil amendments (control, compost (C) 10.0 Mg ha-1, gypsum (G) 100% from gypsum requirement 13.512 Mg ha-1 and G+C).Sub main plots were assigned to foliar application (control (tap water), compost tea (50 L ha-1), proline (3.6 g ha-1), and combination of compost tea + proilne). Generally, results showed that the impacts of main plots were in the following order: compost + gypsum ˃ gypsum ˃ compost ˃ control in both growing seasons. Also, soil amendments had a significant effect on decreasing some soil chemical properties i.e. pH, EC, ESP and increasing of CEC compared control treatment. The treatment compost +gypsum more pronounced the other treatment on soil bulk density and total porosity. Soil basic infiltration rate (IR) and hydraulic conductivity (K) high significantly increased by application of compost, gypsum and gypsum + compost and recorded the highest value by application of compost + gypsum. Chlorophyll, proline content, 1000-grain weight, straw and grain yield of rice were significant increased and recorded the highest values due to the interaction between compost + gypsum and foliar of compost tea and proline during two growing seasons. Water productivity (WP) and productivity of irrigation water (PIW) for grain yield of rice were high significantly increased and recorded the highest values due to the interaction between soil amendments, compost tea and proline. Total return, net return, benefit cost ratio and total return from water unit for rice yield were significant increased with treatment and recorded highest values due the interaction compost + gypsum and foliar  application of compost tea and proline.

This study provides a theoretical framework for the role of renewable energy in mitigating the climate change in the Gulf Cooperation Council (GCC) countries. The abundancy of renewable resources and widely accessible technology are the key drivers for the renewable energy business in the GCC. However, lack of effective policies and regulations, along with subsidized fuel prices, are slowing down the implementation of renewable resource options. This study will illustrate the potential, the challenges, and the barriers of implementing renewable energy technologies in the GCC region. In addition, this research empirically examines the impact of renewable energy sources and other factors in the GCC countries in reducing the carbon dioxide emissions, using pooled ordinary least square regression analysis with fixed effect specification. The results indicate that renewable energy consumption, GDP per capita, and electrical power consumption have a statistically significant impact on CO 2 emissions.

Two field experiments were conducted at the Sakha Agric. Res. Station Farm, Kafr El-Sheikh Gov., North Nile Delta to assess the influence of the alternate furrow irrigation on water conservation and maize productivity during two consecutive summer seasons (2019 and 2020). The location is located at 31 0 -07' N Latitude, 30 0 -57'E Longitude, with an elevation of around 6 m above mean sea level. A randomized complete block design (RCBD) with four repetitions was used to cultivate maize (Giza 310). Irrigation was applied to furrows in three ways: a) watering every furrows (traditional irrigation) with 15-day interval (EFI15), b) alternate irrigation (watering every other furrows) 10-day interval (A1/1E10), and c) alternative irrigation one by one fixed (A1/1C10). During the growing season, one furrow is irrigated while the other is left unwater next door. The following is a summary of the findings: 1-The highest maize yield (3945.55 kg fed -1 ) was obtained with A1/1E10 treatment, while the lowest yield (3703.5 kg fed -1 ) was recorded with the EFI15 system. 2-A1/1E10 was the best irrigation treatment since it achieved the highest grain yield and saved irrigation water by about 19.8% (663.5 m 3 ) compared to the traditional irrigation treatment (EFI15). 3-Alternate irrigation (A1/1E10) recorded the highest values of oil and protein % in grain and increased the benefit-cost ratio (BCR), and net return (NR) as compared with other irrigation regimes. 4-In addition, A1/1C10 treatment achieved the highest water productivity (1.92 kg/m 3 ).

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A greenhouse experiment was conducted at Fac. of Agric., Mansoura University during the two summer successive seasons of 2010 and 2011 aimed to investigate the effect of Ca concentration ( 0.0, 5.0, 10.0 and 20.0 meq / l) in nutrient solution and its application time (pre flowering and post flowering) on tomato fruit composition. Combination between the studied factors levels comprise eight treatments which were arranged in a split block design with 3 replicates . All treatments were studied in the presence of Nconcentration at rate of 150 ppm . The obtained results can be summarized in the following :-Total calcium content of tomato fruit was increased by 19.64 % in the first season and 6.06 % in the second season as a result of post-flowering application of calcium .Relatively higher increases were found in Etha-Ca ( 8.01 % ) and H2O-Ca ( 7.99 % ) in the first season compared with that of the second season ( 1.87 for Etha-Ca , 1.93 for H2O-Ca) due to pre flowering Ca application .Preflowering calcium application reduced Na Cl-Ca (6.82 and 5.94%) ,HAC-Ca (6.38 and 11.54 %) and HCl-Ca (3.19 and 9.34 %) in tomato fruits in both seasons.Increasing calcium levels up to 10.0 meq /l significantly increased total calcium of tomato fruits, while rising calcium level from 10.0 to 20.0 meq /l significantly decreased total calcium content of tomato fruitsin the first season . In the second season, increasing calcium levels up to 10.0 meq /l increased total calcium of tomato fruits but the difference in that trait between treatments of 5.0 and 10.0 meq /l is not detectable . So calcium level of 20.0 meq /l reduced total calcium content by 9.21 % compared with treatment of 10.0 meq /l in the second season .Post-flowering application of Ca at a rate of 5.0 meq/l have the highest value of total Ca in tomato fruits( 4446.9 and 3895.5 ppm in the first and second seasons).Appling 5.0 meq / l treatment achieved the highest values of Eth-Ca in both seasons ( 155.2 and 169.4 ppm for the firs and second season , respectively ). Increasing Ca level above 5.0 meq /l significantly decreasd Eth -Ca in bothseason in tomato fruits .In spite of increasing H2O -Ca form significantly by adding 5.0 meq / l than that of control (60.0 and 65.455 increase in the first and second season ) . Significantly decrease ( comparing to 5.0 meq / l treatment ) with increasing Ca level behind that was found .NaCl -Ca in tomato fruits refer to Ca in pectate form which caused fruit hardness have a strongly increasing trend by increasing Ca level in nutrient solution from 0.0 Ca addition to 5.0 meq /l in nutrient solution) .Na Cl -Ca represent the large portion of Ca in tomato fruit . Post-flowering application of 5.0 meq Ca/l maximize of NaCl-Ca , where 3440 and 2884 ppm Ca were found in this form in the first and second season, respectively . HAC-Ca {Calcium phosphate and Calcium carbonate} in tomato fruits have a strongly increasing trend by increasing Ca level in nutrient solution from 0.0 Ca