Acute and Chronic Phytotoxicity of Subarctic Urban Soils and Industrial Wastes

Soil degradation is a combination of natural and anthropogenic processes that lead to changes in soil functions, quantitative and/or qualitative deterioration of composition and properties, and a decrease in the natural and economic significance of lands. The state of the soil cover in Russia is far from satisfactory, and in some areas even critical. The Murmansk region is highly industrialized and urbanized region in the Arctic zone. We have tested the acute and chronic phytotoxicity of various industrial materials (expanded vermiculite, nepheline waste and quartz waste), urban and suburban soils of industrial, traffic and recreational zones, soil of urban farm, and conditionally background soil. The water-soluble, plant available, and acid-soluble metal fractions were analyzed. To assess the acute toxicity of industrial wastes, pre-grown hydroponic lawns from Lolium spp. were used, and the duration of the experiment was 7 days. The chronic toxicity was assessed using marigolds (Tagetes spp.), after 28 and 60 days. The highest level of metals was found in soils of the suburban zone near the plant of nonferrous metallurgy and in the traffic zones, but it was revealed that the presence of nutrient elements in high concentrations can partly neutralize the toxic effect of these soils. Phytotesting showed that the weak acceleration of roots to the substrate after 3–7 days of exposition is the express indicator of the presence of high concentrations of toxic metals in the substrates and an unfavorable pH level. Thus, we propose the following low-cost algorithm for the rapid field assessment of soil phytotoxicity in the Subarctic: testing of acute phytotoxicity using hydroponic lawns; testing of chronic phytotoxicity using marigolds in case when acute phytotoxicity is absent; the chemical analysis of mobile fractions of heavy metals and nutrients only for soils which revealed the toxic effect to develop the recommendations for improving soil quality or to make decision about their replacing. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.