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In this paper, we made elaborate investigation of the Hall current and radiation effects on MHD heat absorbing unsteady natural convection flow of a viscous incompressible electrically conducting fluid past an impulsively moving infinite vertical plate with ramped temperature and concentration in the presence of first order chemical reaction. The constructing coupled PDEs of the model along with initial and boundary conditions are solved numerically by utilizing the robust FEM. The effects of significant parameters on the primary and secondary velocities, temperature and concentration within the boundary layer are examined. The computational assessment of the primary and secondary shear stresses, rate of heat and mass transfer at the plate surface are put in tabular form. The thermal and mass buoyancy effects elevate both primary and secondary velocity components whilst reverse trend takes place when radiation and chemical reaction parameters are increased. Both primary and secondary velocity components decrease with increasing magnetic parameter whilst opposite trend are noticed with increasing Hall parameter. An increase in Prandtl number and radiation parameter results to reduce temperature distribution. The concentration distribution decreases with increase in Schmidt number and chemical reaction parameter. The significant difference between the fluid velocities is noticed due to the ramped and isothermal boundary conditions. [ABSTRACT FROM AUTHOR]

Determining and predicting both the spatial and temporal variability of soil moisture content is a critical factor in crop production in semi-arid agricultural systems. The objective of this research was to predict the spatial distribution of soil moisture content using ordinary kriging (OK), regression kriging (RK) and cokriging (CK) models. For that purpose, the soil moisture was monitored in the wet period (March, April and May) and dry period (August, September and October) in Kadınhanı district of Konya Province, Turkey. In each monthly sampling period of the study, a total of 278 samples were collected from locations within an area of 29,608.6 ha. The coefficients of variation (CV) of the soil moisture in dry and wet soil conditions were 0.39 and 0.20, respectively. Soil texture, bulk density (BD) and land use were the most important factors influencing soil moisture. In addition, dry soil generally had a smaller nugget effect than wet soil. Overall, CK was able to better estimate the soil moisture content than OK and RK, as evidenced by the smaller mean absolute error (MAE) and mean square error (MSE). RK estimation is more vulnerable to error than CK and OK estimations because the low coefficients of determination in the regression equation lead to increased error and lower confidence in the estimates. The insights generated by the modeling utilized in this study can assist land use planners, land managers and farmers to more efficiently predict, manage and utilize soil moisture content and hence produce larger crops more sustainably. [ABSTRACT FROM AUTHOR]

A pot soil experiment was conducted to investigate the effects of varying soil copper (Cu) concentration on growth, and on its accumulation pattern in different parts of rice plant (Oryza sativa L.) in 2018, Thailand. The treatments imposed were 0, 50, 100, 200, 400 Cu mg/kg (T1 to T5, respectively). Exposure to 100 mg Cu/kg and above at tillering stage; or to 200 Cu mg/kg and above at panicle initiation stage, significantly decreased the plant height. Exposure to 200 Cu mg/kg (T4) produced significantly lower number tillers per pot than T1 or T2. Negative significant correlation between grain yield of rice and soil Cu concentrations was observed. Increasing accumulation of Cu in grain in a dose-dependent manner occurred, with the peak concentration for T3 (11.39 mg/kg). Copper accumulation by tissue had the rank order grain < shoot < root. About 54 to 91% of total absorbed Cu was retained in the root and 2 to 12% of total Cu uptake was translocated to grain. This is beneficial from the point of view of food safety. In other words, the accumulation of Cu in brown rice in current experiment was below the permissible contaminant limit in food, in Thailand. [ABSTRACT FROM AUTHOR]

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