Soil pollution

Soil contamination affects above-ground and below-ground biodiversity in two main ways. Toxicities induced by pollutants may reduce the number of organisms, but changes may also be observed at the community level, as organisms that are tolerant or tolerant will benefit compared to those that are sensitive to the pollutant. There is a nature. It has also been observed that exposure to some trace elements can induce soil microbial resistance and promote antimicrobial resistance (Heydari, 2020). Additionally, soil contamination can enter the food chain and cause disease and death in soil, terrestrial (including humans) and aquatic organisms. Loss of biodiversity and biomass therefore leads to a reduction in organic matter, changes in nutrient input and cycling. This undermines key productivity in natural and agroecosystems, leading to an overall loss of soil ecosystem services. In addition, pollutants can be carried out of the soil by wind and water erosion, making contaminated soil a source of pollution not only for freshwater and marine environments, but also for groundwater through leaching of pollutants. These changes can be gradual or inactive until a tipping point where severe degradation occurs (Baudrot et al., 2018).
Soil degradation and loss of soil ecosystem services

According to Daily (1997), the conditions and processes provided by ecosystem components (both biotic and abiotic) to sustain and maintain human well-being are defined as ecosystem services. With increasing pressure on natural ecosystems, these services need to be evaluated and considered in the decision-making process to ensure continuity for future generations. Soil ecosystem services are provided through interactions between abiotic soil components (soil organic carbon, mineral fractions, soil solutions, pore air) and soil organisms (ranging from genes to macroorganisms). However, constant pressure from a growing population for more services and benefits is depleting and degrading soils worldwide (FAO and ITPS, 2015). Soils are also threatened by global challenges such as biodiversity loss, biogeochemical cycle imbalances, chemical pollution, climate change and hydrogeological cycles, and land use change (Rockström et al. 2009).

Many studies have been conducted on the role of soil in regulating and supplying carbon, nutrients, water and climate (Daily, Matson and Vitousek, 1997; Eswaran, Van Den Berg and Reich, 1993; FAO and ITPS, 2015; Lal Smith et al., 2015; Stevenson and Cole, 1999; Várallyay, 2010). Although the filtering and buffering functions of soils are widely understood, few studies have specifically quantified them (Aslam et al., 2009; Blum, 2005; Burauel and Baßmann, 2005; Keesstra et al. , 2012; Tedoldi et al., 2016) ; Yang et al., 2019). Soils have the ability to retain, buffer, filter and degrade certain contaminants, depending on the nature of the soil and the physicochemical properties of the contaminants. The total concentration of soil contaminants is not directly related to the contaminant's effect on organisms, but depends on the bioavailability of the contaminant. Bioavailability is the amount of a contaminant that can move from soil and cross cell membranes into living tissue (see Glossary). Freely dissolved forms and aqueous complexes are generally the most bioavailable. If contaminants are not physically or chemically retained in the soil matrix and are dissolved or suspended in the soil solution, the contaminants can be directly taken up by plant roots and interact with soil organisms. For example, plant pollutants can be actively or passively transported into root cells, but the molecular mechanisms involved are often not fully understood. For example, the arsenate form of arsenic is absorbed as a phosphate analogue via the P transporter (Danh et al., 2014). The transport of trace elements from roots to shoots is also mediated by transporters