Mid Sweden University

Nicaragua is considered a mining country, and Santo Domingo, Chontales represents one of the centers with the greatest mining activity. The local economy of Santo Domingo depends mainly on mining, however, mining produces environmental contamination and damage, mainly associated with artisanal and small-scale mining that affects not only the quality of environmental resources but also human health and the country's food security. Environmental problems caused by mining activities are a complex situation since the diversity of drivers involved, the environmental and social implications, as well as the mixture of factors that has to be considered to reach a sustainable solution, for this reason, the selection of a viable approach to restore contaminated sites and decrease the environmental impact must be carefully analyzed. The aim of this research was to evaluate the phytoremediation potential of in vitro cassava plants to extract Ag, As, Au, Ba, Cd, Cr, Cu, Hg, and Pb, in mine tailings in Santo Domingo, Chontales, as well as identify the opportunities and limitations of this practice considering the current context. For this, a pilot scale hydroponic experiment was carried out using in vitro plants of cassava Algodon variety in a substrate that contained low-, medium-, and high-concentrations of these elements, as well as controls, in order to determine its phytoremediation potential using its BCF as the main parameter. Plants were established in the contaminated medium for 15 days and then, they were collected, dried, and analyzed by ICP-OES. During the experiment, the morphological parameters and the environmental conditions were recorded. Statistical analysis was performed using R software and the significance of differences among means was determined by one-way ANOVA on ranks. Also, a Driver-Pressure-State-Impact-Response framework was used to analyze and assess the Social-Ecological Systems of mining areas in Santo Domingo, Chontales. The main components of DPSIR were identified using the NERI methodology to analyze the opportunities and limitations of using cassava cultivation as a phytoremediation alternative. In this experiment, the higher BCFs for Pb, Ba, Cu, and Cr were found at lower concentration levels in the order: Pb (464,19) > Ba (207,47) > Cu (22,71) > Cr (10,22). The plants that presented the highest BCF for Ag and Au were found at the medium concentration level (561,52 and 1997,09, respectively). Hg was not detected in the plant tissue (<LOD = 3,15) in any of the three concentration levels. The evaluated plants showed significant differences in the concentration levels only for Ba, Cu, Pb, and the controls (blanks). Therefore, it was determined that the plants accumulate the other elements regardless of their concentration in the medium or substrate. In vitro cassava plants showed adaptation potential to the polluted medium at low- and medium- concentrations. DPSIR analysis results indicate that cassava could represent a viable alternative to phytoremediate contaminated soils in Santo Domingo if the participation of the social leaders and decision-makers could be reached, merged with the environmental education of the local population and using the cassava phytoremediation wastes as an economic alternative for the local population through the production of starch, biofuels and particle board.