Investigating the Effect of Gypsum Powder on Chemical Constituents of Soil and Selected Crops, Adigudem, Tigray, Ethiopia

This paper investigates the effects of gypsum powder from the gypsum plant in Adigudem on chemical properties of soil as well as the yield of two major crops, wheat (Triticum aestivum) and barley (Hordeum vulgare). Three mixes of 10kg of soil with 0%, 10%, 30%, and 50% proportion of gypsum powder were used for pot experiments under glasshouse conditions at Mekelle University. One bulk soil sample was collected from a spot at 4 km from the eastern side of the plant. The chemical concentration of major elements Ca, K, Na, Mg, and Mn, and trace elements, Cd, Zn, Cu, Pb, Cr, and Fe in soil and plant parts were determined using an Atomic absorption spectrometer as well as NO3, PO4 and SO4 using UV-spectrometer. The results suggest that the gypsum powder enhances metals and anion content in soil and in crop parts compared to the control sample. The chemical constituents in soil and crop parts showed negligible variation with increasing proportions of gypsum powder. Gypsum loaded Ca, SO4, Mn, and Pb onto the soil, which exhibited higher Mg, Cu, Mo, Cd, NO3, and PO4 but the comparable concentrations of Fe, K, Zn, and Cr in decreasing order. However, a direct relationship was noted in chemical constituent loadings along the pathway:  powder-soil-crop in a similar fashion in the three mixes. Factor analyses revealed that wheat parts have a higher accumulation of nutrients than the barley parts with higher content in its growth soil blends.  As an extension of this research, the in-situ investigation is recommended to assess the direct impact of the gypsum powder emitted over the soil and crops.