Geoaccumulation and Ecological Risk Indexes in Papaya Cultivation Due to the Presence of Trace Metals

Abstract

The aim of this research was to evaluate the impact of heavy metals on Maradol papaya cultivation soil, through the geoaccumulation index (Igeo) and the ecological potential risk index (RI). Soil samples from 15 locations in the Cotaxtla municipality of Veracruz, Mexico were tested for pH, soil texture, and concentrations of lead (Pb), chromium (Cr), cadmium (Cd), zinc (Zn), copper (Cu), and organic matter (MO). The pH varied between values of 5.5 ± 0.10 and 7.7 ± 0.22, while the MO varied from 1.57% ± 0.97% to 13.1% ± 1.342%. The type of soil texture represented 48% sandy loam, 40% loam, 8% clay loam, and 4% silt-loam. For heavy metals, average levels were found in the following order Cr (0.695 ± 0.018) > Zn (0.615 ± 0.016) > Pb (0.323 ± 0.012) > Cu (0.983 ± 0.011) > Cd (0.196 ± 0.011) mg kg−1. The Igeo values from 96% of the analyzed sampling points were below zero and were considered uncontaminated. The other 4% of samples, from the Potrerillo1 (PT) site, had Igeo values of 1.13, where the highest concentration of Cd was found, which indicates moderate contamination levels. The RI index at the PT site was in the category of moderate contamination, and the rest of the points correspond to the category of low pollution.

Variation of soil properties with sampling depth in two different light-textured soils after repeated applications of urban sewage sludge

“…To determine the extent of trace metal contamination in both layers, a geo-accumulation index was calculated for copper (Cu), zinc (Zn), lead (Pb), and nickel (Ni). This index compares actual concentrations to original contents in soils prior to any anthropogenic activity (Tendaupenyu and Magadza, 2019;Amaro-Espejo et al, 2020). Because of the sensitivity of microorganisms to soil contamination and/or physical degradation, we also investigated heterotrophs and enzyme activities in both soils.…”

The impact of the mountain barrier on the spread of heavy metal pollution on the example of Gorce Mountains, Southern Poland

“…The geoaccumulation index (I geo ) is a quantitative index used to study the degree of heavy metal pollution in soils and sediments (Amaro-Espejo et al, 2020;Fazekašová et al, 2021;Gąsiorek et al, 2017). It is calculated as follows:…”