TITLE:
A Systematic Review of Heavy Metals in Irrigation Water and Their Effects on Agricultural Soil Quality and Crop Production in Ghana
AUTHORS:
Adutwumwaa Victoria, Daniel Nyamekye Nnebini
KEYWORDS:
Agricultural Impacts, Crop Yield, Food Safety, Heavy Metals, Irrigation Water, Soil Quality
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.13 No.1,
January
13,
2025
ABSTRACT: This study examines the impacts of heavy metals in irrigation water on soil quality and crop productivity in Ghana. Data was synthesized from 41 studies across 10 study areas spanning seven regions in Ghana. 10 heavy metals were identified from the synthetized data, namely, cadmium (Cd), lead (Pb), arsenic (As), mercury (Hg), manganese (Mn), zinc (Zn), copper (Cu), cobalt (Co), nickel (Ni), iron (Fe) and chromium (Cr). The synthesized data revealed that certain regions such as Upper East, Ashanti and Ahafo exhibits elevated cadmium level in soil and the western region showed high concentrations of Hg, As, Pb, and Cu exceeding WHO limits in irrigation water. Due to their economic importance and susceptibility to metal contamination, the analysis of the effects of these metals on crop productivity focused on maize and leafy vegetables. The findings show that metals such as As, Ni, and Cu, in irrigation water significantly affect soil metal concentration but do not affect crop productivity, but Hg, Zn, Pb, and Co rather influence crop yield. Interestingly, while Hg and Pb reduce yield in leafy vegetables, they positively affect maize productivity, highlighting the potential for tailored crop selection based on soil metal concentration to improve Agricultural outcomes.