Chemical Equilibrium Dynamics and Distribution of Trace and Heavy Elements in Agricultural Systems of Misurata: A Comparative Geochemical Study

Abstract

This study evaluated the geochemical status of agricultural soils in Misrata, Libya, across four primary sites (Ad-Dafniyah, Karzaz, Abu Ruwayah, and Tommina) to determine the impact of soil pH on the spatial distribution and bioavailability of trace elements (Fe, Mn, Zn) and heavy metals (Pb, Ni) at two sampling depths (10 cm}and (20 cm). The results revealed a predominant strong alkalinity (Ph>8.5), which acts as the main factor constraining micronutrient bioavailability. Despite high total iron (Fe) concentrations reaching (2620 μg g^-1), the element exhibits a functional deficiency due to chemical precipitation and fixation in the alkaline medium. Additionally, a distinct geochemical anomaly for lead (Pb) was identified in Ad-Dafniyah at the sub-surface depth (1222 μg g^-1), indicating localized anthropogenic input. The study demonstrates that agricultural soil quality in Misrata is governed by chemical equilibrium rather than total mineral abundance, and recommends localized soil acidification techniques to solubilize precipitated minerals and enhance plant nutrient uptake.