Heavy Metal Contamination in Arenillas Ecological Reserve Soils: Correlation and Conservation Impact

ABSTRACT This study addresses the critical knowledge gap regarding heavy metal contamination in the soils of the Arenillas Ecological Reserve (AERv), located on the southwest coast of Ecuador. Despite being a fragile and highly biodiverse ecosystem, little is known about the magnitude, spatial distribution, and drivers of heavy metal contamination in this reserve. Soil samples were collected at a depth of 0 to 10 cm from mangrove areas (MANg), salt marshes (SMe), and dry forests (Df) to assess concentrations of copper (Cu), manganese (Mn), iron (Fe), zinc (Zn), lead (Pb), and chromium (Cr) and their correlation with physicochemical properties. Analytical methods included one‐way ANOVA, Pearson correlation, cluster analysis (CA), and the application of the geo‐accumulation index ( Igeo ) and pollution load index ( PLI ) to quantify contamination levels. The results reveal elevated concentrations of heavy metals in MANg, SMe, and the southern dry forest (Df‐S5), exceeding thresholds reported in previous studies. Notably, Zn and Pb contamination levels range from high to very high across the reserve, with MANg soils being the most impacted by all metals studied. The accumulation patterns are closely linked to soil properties such as silt and clay content, porosity, pH, and organic matter, which influence metal retention and mobility. This contamination is primarily attributed to anthropogenic activities, including shrimp farming, conventional agriculture, and pollutants originating from mining, domestic, and industrial discharges from nearby urban areas. These findings underscore the urgent need for targeted restoration and conservation measures to safeguard the reserve's biodiversity and ecosystem services. They also highlight the necessity for updated regulations and mitigation strategies to manage contamination effectively, offering a foundation for sustainable management practices in the AERv and other protected areas in Ecuador.