Sewage sludge is an effective fertilizer in many soil types. When applied as an amendment, sludge introduces, in addition to organic matter, plant nutrients into the soil. When applied for cropland as a fertilizer, the mass loading of sewage sludge is customarily determined by inputs of N and/or P required to support optimal plant growth and a successful harvest. This study aims to examine the changes in organic matter contents and nitrogen forms in sludge-amended soils, as well as the growth of corn and faba bean plants. The main results indicated that there were higher responses to the corn and faba bean yields when sludge was added. Levels of organic carbon in soil were higher after maize harvest and decreased significantly after harvesting of beans, and were higher in sludge amended soils than unmodified soils, indicating the residual effect of sludge in soil. NO3−-N concentrations were generally higher in the soil after maize harvest than during the plant growth period, but this trend was not apparent in bean soil. The amounts of NH4+-N were close in the soil during the growth period or after the maize harvest, while they were higher in the soil after the bean harvest than they were during the growth period. Total nitrogen amounts were statistically higher in the soil during the growth period than those collected after the corn harvest, while they were approximately close in the bean soil. The total nitrogen amount in corn and bean leaves increased significantly in plants grown on modified sludge soil. There were no significant differences in the total nitrogen levels of the maize and beans planted on the treated soil.

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Barley is a globally important strategic cereal crop, which grows well under various climatic and drought-stress conditions. In Egypt, barley is a major winter crop cultivated in old and newly reclaimed lands that suffer from a lack of irrigation, low soil fertility, and salinity of both soil and water. However, there is a lack of awareness of the nutritional role of barley for both humans and animals. Therefore, this paper aims to evaluate the actual status of cultivated areas of barley, especially in newly reclaimed lands in Egypt during the period (2004/2005–2018/2019). The study is based on descriptive and quantitative analysis using means, growth rates, relative importance, and robust regression. Results show that barley cultivated areas in newly reclaimed lands represented about 76.9% of total cultivated areas during (2004/2005–2018/2019). It means that barley is more adaptable in dry and marginal areas, meaning it is a sustainable plant that can face drought, land degradation, and climate change. Also, production costs, farm prices, and net return of barley are the most important factors that affect the producer’s decision to cultivate barley during the study period. In addition, there is excessive use of some variables during the study period; after estimating the production function of barley using robust regression, it is shown that it is necessary to reduce these variables in the production process to achieve economic efficiency.

Opuntia ficus-indica is gaining scientists' and policy makers' interest worldwide as drought tolerant crop adopted to marginal low fertile soils. Few studies were conducted to estimate its water management parameters under different soil-climate conditions. O.ficus-indica was planted in the experimental farm of City of Scientific Research and Technological Applications (SRTA-City, Alexandria, Egypt) under different irrigation scheduling applications. The study aimed to understand the effect of severe water deficit on crop development and water management related parameters. First irrigation scheduling (T1) applied irrigation with fixed amount of water (7.2 m 3 ha -1 week -1 ). The second (T2), was applied when soil water content (SWC) became below 35% of field capacity (Ɵfc) in effective root zone. The third (T3), was conducted when SWC was below 30% of Ɵfc. The results revealed higher yield under T1 than T2 and T3. Water productivity was the lowest in T1 (0.62 kg m -3 ) and the highest in T3 (18.13 kg m -3 ). Actual crop evapotranspiration (ETa) was significantly higher in T3 (4.80 mm day -1 ), than T2 (4.56 mm day -1 ) and T1 (3.84 mm day -1 ). No significant difference was found in soil water content, canopy cover, crop coefficient among the applied irrigation scheduling. Average canopy cover was 13.63%, 11.08%, and 10.22% for T1, T2, and T3, respectively indicating early crop development stage. The corresponding crop coefficient (kc) was between 0.19 in T1 to 0.23 in T2 and 0.24 in T3. Further study is recommended to confirm obtained results and estimate ETa and kc under middle and end crop development stages.