INDUROT and Environmental Biogeochemistry and Raw Materials Group, Campus de Mieres, Universidad de Oviedo, Mieres, Asturias, Spain.
INDUROT and Environmental Biogeochemistry and Raw Materials Group, Campus de Mieres, Universidad de Oviedo, Mieres, Asturias, Spain.
J Environ Manage. 2021 Oct 15;296:113179. doi: 10.1016/j.jenvman.2021.113179. Epub 2021 Jul 12.
Mining and biomass waste were used to remediate a brownfield affected by As, Cd, Cu, Pb and Zn pollution in a pilot scale experiment, and a plant used for phytoremediation purposes was used as an indicator of possible toxicological effects. To carry out the experiments, plots in field conditions were treated with magnesite (mining waste), magnesite-sludge compost, and magnesite-biochar respectively, while untreated soil was used as a control. The plots were then irrigated and left for one week, after which seeds of the ryegrass Lolium perenne L. were sown. Soil properties such as metal(loid) availability, pH, phosphorus availability, total nitrogen, organic carbon, and nutrients were monitored for two months. Finally, the ryegrass was harvested and pollutant concentrations were analyzed in the aerial parts. Magnesite proved to be an excellent amendment for metal(loid) immobilization, although the notable increase in soil pH and Mg content inhibited plant growth. However, the application of magnesite in combination with the sludge compost (rich in N and P) favored plant growth and also immobilized metals, although As availability increased. In contrast, the analysis of plants in this treatment revealed lower As and metal concentrations than those grown in the untreated soil. In turn, the application of magnesite and biochar was also effective in reducing metal(loid) availability; however, the plants did not grow under these conditions, probably due to the low N and P content of biochar. In this regard, the combined application of mining waste and sludge compost emerges as a useful nature-based solution for soil remediation in the context of the circular economy.
在一个试点规模的实验中，利用矿业和生物质废物来修复受 As、Cd、Cu、Pb 和 Zn 污染的棕地，并使用一种用于植物修复目的的植物作为可能的毒理学效应的指示剂。为了进行实验，在田间条件下的地块分别用菱镁矿（矿业废物）、菱镁矿-污泥堆肥和菱镁矿-生物炭进行处理，而未处理的土壤则作为对照。然后对这些地块进行灌溉并放置一周，之后播种黑麦草 Lolium perenne L. 的种子。监测了两个月的土壤性质，如金属（类）的可用性、pH 值、磷的可用性、总氮、有机碳和养分。最后，收割黑麦草，并分析其地上部分的污染物浓度。菱镁矿被证明是一种很好的固定金属（类）的改良剂，尽管土壤 pH 值和 Mg 含量的显著增加抑制了植物的生长。然而，菱镁矿与污泥堆肥（富含 N 和 P）的联合应用有利于植物的生长，同时也固定了金属，尽管 As 的可用性增加了。相比之下，在这种处理下分析的植物中的 As 和金属浓度低于在未处理土壤中生长的植物。反过来，菱镁矿和生物炭的应用也有效地降低了金属（类）的可用性；然而，在这些条件下，植物无法生长，可能是由于生物炭的 N 和 P 含量低。在这方面，矿业废物和污泥堆肥的联合应用作为一种基于自然的解决方案，在循环经济背景下，对于土壤修复是有用的。
