Laboratory of Microbial Biotechnology, Agrosciences, and Environment (BioMAgE), Labeled Research Unit-CNRST N°4, Faculty of Sciences Semlalia, Cadi Ayyad University, Marrakech, Morocco.
Department of Soil Science and Soil Ressources, Institute of Geography, Ruhr University Bochum, Universität Strasse 150, 44801, Bochum, Germany.
J Environ Manage. 2024 Dec;371:123035. doi: 10.1016/j.jenvman.2024.123035. Epub 2024 Oct 30.
Rising global metal demand has led to extensive mining, leaving post-mining landscapes with degraded soil and metal contamination. The exacerbated heavy metals concentrations deteriorate soil microbial activity and consequent microbial biomass, enzymatic activities, and organic matter are impaired. This study explores nature-based solutions, focusing on assisted natural remediation and organo-mineral amendments: marble waste (Mw), clay (Cy), and compost (Cp). Lupinus angustifolius L., a key bioremediator, is highlighted for its role in mine rehabilitation, adaptation to extreme edaphic conditions, and contribution to enhanced nutritional status. The specific aim of this study is to evaluate the synergetic impact of the use of L. angustifolius with four soil combined treatments (Com): Com: Cy-Cp-Mw; Com: Cy-Cp-Mw; Com: Cy-Cp-Mw; and Com: Cy-Cp-Mw. As a practical approach to sustainable mining soil rehabilitation, it emphasizes soil microbial biomass and activity, soil fertility, plant growth, and heavy metal immobilization in a concise and impactful manner. These combinations were used as the soil substrate material for a four-month greenhouse experiment where plant growth parameters, heavy metal accumulation, soil properties, microbial activity, and bioavailable metal content were determined. The study underscored the positive effects of the treatments Com, Com, and Com on heavy metal mobility, microbial biomass, and carbon, nitrogen, and phosphorus-acquiring enzymes. Notably, bioavailable heavy metals were effectively reduced, with copper, zinc, and lead decreasing up to 2-fold, 2-fold, and 1.8-fold, respectively. Microbial biomass and soil enzyme activities responded positively to our amendments, indicating improved nutrient cycling. Microbial biomass carbon increased up to 4-fold, and similarly, β-glucosidase, N-acetyl-ß-glucosaminidases, L-Arginase, and acid phosphatase (Pho) increased up to 1.9-fold, 47-fold, 12.85-fold, and 2-fold, respectively. Furthermore, soil carbon and nitrogen contents increased up to 11.15-fold and 9.41-fold, respectively. This study suggested a positive and impactful influence on the intricate processes of soil carbon and nitrogen cycling, indicative of increased microbial activity, and offered a nature-based solution to mitigate the environmental impact of extensive mining.
全球金属需求的增长导致了广泛的采矿活动，使采后景观的土壤退化和受到金属污染。加剧的重金属浓度会降低土壤微生物的活性和随后的微生物生物量，从而损害酶活性和有机质。本研究探讨了基于自然的解决方案，重点是辅助自然修复和有机-矿物改良剂：大理石废料 (Mw)、粘土 (Cy) 和堆肥 (Cp)。窄叶羽扇豆 (Lupinus angustifolius L.) 作为一种关键的生物修复剂，因其在矿山修复、适应极端土壤条件以及促进营养状况改善方面的作用而受到关注。本研究的具体目的是评估使用窄叶羽扇豆与四种土壤组合处理 (Com) 的协同影响：Com: Cy-Cp-Mw; Com: Cy-Cp-Mw; Com: Cy-Cp-Mw; 和 Com: Cy-Cp-Mw。作为一种可持续采矿土壤修复的实用方法，它以简明而有影响力的方式强调了土壤微生物生物量和活性、土壤肥力、植物生长和重金属固定。这些组合被用作为期四个月的温室实验的土壤基质材料，在实验中测定了植物生长参数、重金属积累、土壤特性、微生物活性和生物可利用金属含量。研究强调了 Com、Com 和 Com 处理对重金属迁移性、微生物生物量和获取碳、氮和磷的酶的积极影响。值得注意的是，有效降低了生物可利用重金属，铜、锌和铅分别降低了 2 倍、2 倍和 1.8 倍。微生物生物量和土壤酶活性对我们的改良剂有积极响应，表明养分循环得到改善。微生物生物量碳增加了 4 倍，类似地，β-葡萄糖苷酶、N-乙酰-β-葡糖胺酶、L-精氨酸酶和酸性磷酸酶 (Pho) 分别增加了 1.9 倍、47 倍、12.85 倍和 2 倍。此外，土壤碳和氮含量分别增加了 11.15 倍和 9.41 倍。本研究表明，对土壤碳和氮循环的复杂过程产生了积极而有影响力的影响，表明微生物活性增加，并为减轻广泛采矿的环境影响提供了一种基于自然的解决方案。
