Effect of Bypass-Flow on Leaching of Salts in a Cracking Soil in the Nile Delta

Salinity is a major threat to the sustainability of irrigated agriculture in arid and semi-arid regions. Leaching is the primary measure for removing excess salts from the root zone, but not all water applied to the soil surface contributes to the removal of salts. In clayey soils, bypass flow along cracks can occur without being mixed with saline pore water in the matrix. To present a field dataset to quantitatively evaluate the contribution of bypass flow to the leaching of salts, soil sampling and monitoring of groundwater and discharge from a tile drain were carried out in farmland having a cracking soil in the Nile Delta. The electrical conductivities of 1:2 extracts were measured to evaluate the salinity of the soil. The first evidence for the occurrence of significant bypass flow through cracks was the salinity of the pore water, which was nearly triple that of the shallow groundwater and outflow from drainage. Second, the difference in root zone salinity before and after paddy rice cultivation was not significant. Third, the gradient of the groundwater table was very small. in spite of the low saturated hydraulic conductivity. Fourth, the salinity of the outflow from the tile drain dropped just after irrigation or rain. These results indicated that bypass flow through cracks played a significant role in the drainage process in the soil, and that nearly half of the water bypasses through cracks in the field with a cracking soil

Determining Irrigation Depths for Soybean Using a Simulation Model of Water Flow and Plant Growth and Weather Forecasts

A new scheme to determine irrigation depths using a two-point of predicted cumulative transpiration over irrigation interval is presented. Rather than maximizing water use efficiency, this scheme aims to maximize net income. The volumetric water price is considered to give farmers an incentive to save irrigation water. A field experiment for soybeans was carried out in the Arid Land Research Center, Tottori University, Japan in 2019. The total irrigation amount yield and net income by the proposed scheme were compared to those by a tensiometer-operated automated irrigation. The scheme could save irrigation water by 16% with a yield increment of 20%; resulting in a 22% increase in net income compared to the automated irrigation. The model simulated the volumetric water content in the effective root zone of the plant in fair agreement. These results indicate the effectiveness of the proposed scheme that may replace an automated irrigation system even considering uncertainty in weather forecast to determine irrigation depth and secure investment costs

Impact of YouTube Influencers on Consumer Purchase Intention with the Mediating Influence of Brand Awareness: An Applied Study on University Students in Tabuk

This paper aims to study the impact of YouTube influencers on consumer purchase intention with the role of brand awareness as mediator evidence from Tabuk. The key objectives include (1) to examine the impact of YouTube influencers on consumer purchase intention; (2) to examine the impact of YouTube influencers on brand awareness; (3) to examine the impact of brand awareness   on purchase intention ;(4) to examine the impact of Influencers on YouTube who can affect consumer behavior through brand awareness. The research hypotheses, which were based on prior studies and the study's factors, were adopted for the study at the University of Tabuk in Saudi Arabia. The researcher used the descriptive analytical method; The Data was collected through Field research (questionnaire) among 150 respondents. The results showed that there was a positive correlation   between YouTube influencers credibility dimensions and consumer purchase intention of university students. The finding showed that there was a positive correlation between brand awareness and consumer purchase intention of university students.  This study recommends that influencers play a significant role in shaping consumer purchase intention, the study suggested to the marketing managers to select attractive influencers to represent their brands, thus brands should choose influencers who have strong personalities, good physical appearances and have the reputation of being trustworthy. The study recommends that Influencers marketing is useful for creating Brand awareness

Impact of YouTube Influencers on Consumer Purchase Intention with the Mediating Influence of Brand Awareness: An Applied Study on University Students in Tabuk

This paper aims to study the impact of YouTube influencers on consumer purchase intention with the role of brand awareness as mediator evidence from Tabuk. The key objectives include (1) to examine the impact of YouTube influencers on consumer purchase intention; (2) to examine the impact of YouTube influencers on brand awareness; (3) to examine the impact of brand awareness   on purchase intention ;(4) to examine the impact of Influencers on YouTube who can affect consumer behavior through brand awareness. The research hypotheses, which were based on prior studies and the study's factors, were adopted for the study at the University of Tabuk in Saudi Arabia. The researcher used the descriptive analytical method; The Data was collected through Field research (questionnaire) among 150 respondents. The results showed that there was a positive correlation   between YouTube influencers credibility dimensions and consumer purchase intention of university students. The finding showed that there was a positive correlation between brand awareness and consumer purchase intention of university students.  This study recommends that influencers play a significant role in shaping consumer purchase intention, the study suggested to the marketing managers to select attractive influencers to represent their brands, thus brands should choose influencers who have strong personalities, good physical appearances and have the reputation of being trustworthy. The study recommends that Influencers marketing is useful for creating Brand awareness

A new scheme to optimize irrigation depth using a numerical model of crop response to irrigation and quantitative weather forecasts

Irrigation management can be improved by utilizing advances in numerical models of water flow in soils that can consider future rainfall by utilizing data from weather forecasts. Toward this end, we developed a numerical scheme to determine optimal irrigation depth on scheduled irrigation days based on a concept of virtual net income as a function of cumulative transpiration over each irrigation interval; this scheme combines a numerical model of crop response to irrigation and quantitative weather forecasts. To evaluate benefits, we compared crop growth and net income of this proposed scheme to those of an automated irrigation method using soil water sensors. Sweet potato (Ipomoea batatas (L.), cv. Kintoki) was grown in 2016 in a sandy field of the Arid Land Research Center, Tottori University, Japan under either a non-optimized automated irrigation or the proposed scheme. Under the proposed scheme, 18% less water was applied, yield increased by 19%, and net income was increased by 25% compared with the results of the automated irrigation system. In addition, soil water content simulated by the proposed scheme was in fair agreement with observed values. Thus, it was shown that the proposed scheme may enhance net income and be a viable alternative for determining irrigation depths

Optimization of Irrigation and Leaching Depths Considering the Cost of Water Using WASH_1D/2D Models

Optimization of water use with consideration of salinity control is a crucial task for crop production. A new scheme, “optimized irrigation”, was recently presented to determine irrigation depth using WASH_1D/2D which are numerical simulation models of water flow and solute transport in soils and crop growth. In the scheme, irrigation depth is determined such that net income is maximized considering the price of water and weather forecasts. To evaluate whether the optimized irrigation is also able to restrict salinity stress and avoid salinization without any intentional leaching, we carried out a numerical experiment for winter wheat grown in northern Sudan under the following scenarios: (1) Available water in the root zone is refilled using freshwater (0.17 g/L of NaCl) at every five days; (2) available water in the root zone is refilled using saline water (1.7 g/L) at every five days; (3) optimized irrigation using fresh water at 7-days interval; (4) optimized irrigation on a weekly basis using saline water; and (5) same as scenario 2, except for leaching is carried out at the middle of the growing season and leaching depth is optimized such that net income is maximized. The results showed that the optimized irrigation scheme automatically instructs additional water required for leaching at each irrigation event and maximizes the net income even under saline conditions