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While abundant scientific literature focuses on diagnosing contaminated areas, solutions with a scientific base are far from balanced. This is the case of the Quintero‐Puchuncaví Bay, a widely known contaminated area in the central coast of Chile. Here, arsenic in soils surrounding the industrial complex has been reported as a threat to human health. However, land planning based on As contamination becomes a challenge since the whole area is identified as contaminated. Such a lack of land‐planning constrains the occupation and remediation of contaminated soil leading to a brownfield‐like landscape. To face this challenge, we proposed using a geospatial decision support system (S‐DSS) to integrate the contamination assessment, health and ecosystem risks, and potential land uses. When characterizing soil arsenic concentration thresholds for different land uses in a S‐DSS, we could categorize the land in suitable, caution, and unsuitable areas (based on human health risks). This way, we unravel areas with potential use in the current condition while also discerning caution and unsuitable categories, that can undergo extensive and intensive remediation techniques. Similarly, we took a conservational approach to estimate emerging risk from the industrial complex associated to explosions. Altogether, it highlights the potential of S‐DSS to integrate different geographic information. We finally feature two APPs regarding current land‐use suitability and a modeled one considering future arsenic emissions. [ABSTRACT FROM AUTHOR]

The process of passive revegetation of chemically degraded soils through assisted remediation was assessed under field conditions 6 years after amendment application. In 2009, three treatments were applied: unamended soil (untreated), soil amended with lime, and soil amended with lime + compost. For each field plot, main soil physico-chemical characteristics were determined (pH, organic matter, moisture content at field capacity and exchangeable Cu), while plant colonist development was assessed (plant cover and aboveground biomass). The same evaluation was carried out in 2015. A single application of amendments maintains a neutral pH after 6 years. Thus, neutralization of the soil acidity was stable over time. In 2009, lime + compost was the best treatment for increasing the plant cover. Although the soil organic matter content decreases in year 6, plant cover remained stable over time in this treatment. Incorporation of both organic matter and lime was pivotal at the beginning of the revegetation process, allowing the creation of a potentially self-sustaining ecosystem. No maintenance and/or additional application of amendments was required. Aboveground biomass showed differences between years, possibly explained by changes in climate conditions between 2009 and 2015, and/or changes in nutritional conditions (soil fertility) and plant competition. Plant biodiversity in year 6 was similar for all treatments. The long-term results of plant cover show lime and specially lime + compost as promising amendments to revegetate polluted soils of the Puchuncaví Valley. [ABSTRACT FROM AUTHOR]

Soil amendments may decrease trace element accumulation in vegetables, improving food security and allowing the recovery of contaminated farmlands. Despite some promising results in the laboratory, validation of soil amendments in field conditions are scarce, especially in aerobic soils. Here, we assessed the effect of different potential soil amendments on arsenic (As) accumulation in lettuces. Then, we compared them in terms of food security and the associated investment (efficacy and efficiency, respectively). We also hypothesized that the soil amendments do not lead to side effects, such as yield decrease, phytotoxicity of Cu, or undesired changes in soil properties. Thereby, we assessed lettuces grown on untreated contaminated soils (C+), treated contaminated soils, and untreated uncontaminated soils (C−) in two contrasting soil types (sandy and loamy soils). The treated contaminated soils consisted of multiple soil amendments. Soil amendments were: diammonium phosphate (DP), iron sulfate (IS), ferrous phosphate (FP), calcium peroxide (CP), and organic matter (OM). We found that phosphate amendments (DP and FP) reduced the As in edible tissues of lettuce in both areas, while CP only reduced As accumulation in the sandy soils area. The As intake through lettuces grown on these amended soils was about 30% lower than on the unamended ones. Cu concentrations in lettuces above 25 mg kg−1 grown in contaminated soils without reducing growth were found, a result that differed from non-field studies. [ABSTRACT FROM AUTHOR]