Assessment of Indexes for Heavy Metal Contamination in Remote Areas: A Case Study in a Pyrenean Forest, Navarra, Spain

Abstract

The objective of the present work was to verify and compare the performance of different geochemical indices employed to identify the anthropogenic origin of selected heavy metals and other trace elements in soils. To that end, two background values, the upper continental crust and the metal content in the bed rock, were used and obtained from a forested basin of the western Pyrenees. The enrichment factor (EF), geo-accumulation index (I), and contamination factor (C) were finally evaluated for their ability to determine anthropogenic contamination: Results indicate that an in-depth knowledge of the bed rock geochemistry and the geological background content is essential to distinguish between the natural variability of soils and any anthropogenic contribution of heavy metals. Although both EF and C show a similar ability to detect soil contamination, the latter is proposed as a more appropriate and sensitive marker given its ability for finding episodically elevated contamination levels.

Transfer and transformation characteristics of Zn and Cd in soil-rotation plant (Brassica napus L and Oryza sativa L) system and its influencing factors

“…In China, excess rates of heavy metals were found in 19.4% of farmland soil, significantly higher than that in grasslands, forests, and other environmental types 3 . According to the Chinese Soil Environmental Quality Standard (CSEQS) GB 15618-2018, high geological background levels (unusually high levels of heavy metals in soils and their parent materials) are an important factor leading to excessive heavy metals in the soil 4 – 6 . Southwest China is an area with typically high geological background levels 1 , 7 .…”

Study on the effects of several amendments on the antioxidant defense system of Chinese cabbage in heavy metal contaminated soil

“…Due to the disposal of contaminated sewage sludge, the overuse of chemical fertilizers, and the rapid growth of industrialization and urbanization, anthropogenic processes have accelerated soil pollution (Li et al, 2017;Kamran et al, 2020). On the other hand, heavy metals come from endogenous pollution, mainly due to the high content of heavy metals in the parent material itself, which leads to the accumulation of heavy metals in the soil (Delia et al, 2016).…”