Krystyna Ciarkowska

Enzyme activity as an indicator of soil-rehabilitation processes at a zinc and lead ore mining and processing area

The activities of soil enzymes in relation to the changes occurring in the soil on a degraded area in southern Poland after zinc and lead mining were analyzed. An evaluation of the usefulness of urease and invertase activities for estimating the progress of the rehabilitation processes in degraded soil was performed. The data show that the soil samples differed significantly in organic carbon (0.68-104.0 g kg(-1)) and total nitrogen (0.03-8.64 g kg(-1)) content in their surface horizons. All of the soil samples (apart from one covered with forest) had very high total concentrations of zinc (4050-10,884 mg kg(-1)), lead (959-6661 mg kg(-1)) and cadmium (24.4-174.3 mg kg(-1)) in their surface horizons, and similar concentrations in their deeper horizons. Nevertheless, the amounts of the soluble forms of the above-mentioned heavy metals were quite low and they accounted for only a small percentage of the total concentrations: 1.4% for Zn, 0.01% for Pb and 2.6% for Cd. Urease activities were ranked as follows: soil from flotation settler (0.88-1.78 μg N-NH4(+) 2h(-1) g(-1))<soil from old slag heaps (1.77-2.51 μg N-NH4(+) 2h(-1) g(-1))<soil undisturbed by mining activity (2.14-5.73 μg N-NH4(+) 2h(-1) g(-1)). Invertase activities were similar in soil that was undisturbed by mining and in soil from old slag heaps, ranging from 20.5 to 77.1mg of the inverted sugar, but they were much lower in soil from the flotation settler (0.12-6.95 mg of the inverted sugar). The results demonstrated that heavy pollution with Zn, Pb and Cd slightly decreased the activities of urease and invertase. It is thought that it resulted from the enzyme reactions occurring in slightly acidic or alkaline soil conditions. Under such conditions, heavy metals occur mainly in insoluble forms. The activities of these enzymes are strongly dependent on the content and decomposition of organic matter in the soil.

Natural Organic Amendments for Improved Phytoremediation of Polluted Soils: A Review of Recent Progress

Abstract Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air. Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes (such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However, the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.

Phytostabilization of Zn-Pb ore flotation tailings with Dianthus carthusianorum and Biscutella laevigata after amending with mineral fertilizers or sewage sludge

Zinc-lead mining wastes remain largely unvegetated and prone to erosion for many years because of phytotoxic levels of residual heavy metals, low nutrient status and poor physical structure. The optimal solution for these areas is to restore plant cover using species which spontaneously appear on the spoils. These species are adapted to the conditions of tailings, and their establishment will promote further vegetation by increasing soil organic matter and development of a soil system capable of supporting the nutrient and water requirements of plants and microoorganisms. The potential of Dianthus carthusianorum and Biscutella laevigata to stabilize mine spoils was analysed in a three-year pot experiment. Post-flotation wastes accumulated after Zn and Pb recovery from ores, were collected from tailings and used as a substrate for plant growth. Seeds for seedling production were collected from plants growing spontaneously on mine tailings. Prior to the establishment of the three-year pot experiment, the substrate was amended with fertilizer NPK or municipal sewage sludge, supplemented with K2O (SS). Substrate samples were collected for chemical analyses, dehydrogenase and urease activities measurements each year at the end of the growing season. The plants were harvested three years after the amendments. Both tested plant species were equally suitable for revegetation of the tailings. The amendment including both SS and NPK resulted in an increase of Corg, Nt, available P, K, Mg contents, an increase of dehydrogenase (DHA) and urease activities and a decrease in the concentrations of the soluble forms of Zn, Pb and Cd. However, nutrient content, DHA activity and plant biomass were higher with SS than NPK addition. NPK application enhanced the substrate properties after the first growing season, while positive effects of SS use were still observed after three years. A longer-lasting positive effect of SS than NPK application was probably due to the high organic matter content in SS, which was gradually decomposing and releasing nutrients.

Microstructure of humus horizons of gypsic soils from the Niecka Nidzianska area (South Poland)

Abstract The microstructure of the humus horizons of gypsic soils belonging to lithic, mollic and cambic rendzic Leptosols [FAO/UNESCO, Soil Map of the World. ISRIC, Wageningen, 1997.] from the Niecka Nidzianska area (South Poland) was studied. Soil samples were collected from humus horizons of 24 profiles of soils which differed in many ways such as geomorphological position (on slopes with north or south exposure and on flat terrain); depth of profiles (shallow and deep soils) as well as land use (arable and covered by natural vegetation). The following properties were determined: pH, the level of organic carbon, the total nitrogen, clay content and CaCO3 content. Thin sections were made of undisturbed soil samples. The investigated soils were characterized by considerable biological activity and abundance in humus with varied microstructures. Regarding microstructures, the investigated soils were divided into four groups. The first group consists of shallow rendzinas from the southern slopes, overgrown with feather-grass steppe with a fine-pelleted humicol microstructure formed mainly of isotropic aggregates of animal origin, mainly pellets of Oribatei and Collembola and less numerous of Enchytraeidae. The second group is formed by soils of the northern slopes covered by grass with sesleria, sedge and anemone with a coarse-pelleted humicol microstructure made up of fecal pellets of Collembola, Coleoptera larvae, Enchytraeidae and Diplopoda. Deep grassland soils rich in perennial dicotyledonous plants from the flat areas with a fine-pelleted mullicol microstructure show abundant effects of the activity of Lumbricidae, Enchytraeidae, Diplopoda, and larvae of Coleoptera and Diptera forming a very porous material which belongs to the third group. Medium deep and deep arable soils with a spongy mullicol microstructure that is of mixed organo-mineral colloidal complexes with visible grains of skeleton belong to the last group.

Enzyme Activities in Soils Contaminated with Heavy Metals in Varying Degrees

This chapter addresses the issue connected with the way the activity of soil enzymes responds to the pollution of soils caused by heavy metals. Firstly, the role and a brief characterization of selected soil enzymes as well as natural environmental factors which influence enzyme activity of soils are presented. Then, the mechanisms connected with the impact of heavy metals on the enzyme activity are explained. In order to give an insight into the effects of short-term soil contamination by Zn, Pb, Cd, Cr, and Ni, individually or in combinations of metals, research findings based on pot and incubation experiments are analyzed. Furthermore, an overview of the research regarding the effects of long-term influence of heavy metals on the enzyme activity is given. The usefulness of enzyme activity analyses for determining the level of degradation and the progress of ecosystem restoration is also discussed. Finally, the reasons for using the soil enzyme activity as an indicator of changes in soil properties caused by environmental stress such as heavy metal pollution are provided.

Naturalistic gardens as a recommended solution for the conservation of local biodiversity in degraded areas.

Abstract The development of the art of garden design has brought about the emergence of naturalistic or ecological gardens. This paper presents a brief historical overview of this period in gardening, and provides examples of contemporary applications. Plants can function as absorbents of metals and therefore there is also the possibility of their practical application in techniques for purifying the environment from metallic contamination. An urgent need to create collections of this unique wild plant material has been stressed. Naturalistic gardens designed in appropriate areas have been proposed as an adequate form of setting up in vivo collections composed of numerous native taxa.

Assessment of heavy metal pollution risks and enzyme activity of meadow soils in urban area under tourism load: a case study from Zakopane (Poland)

Effect of tourism, especially skiing activities, and urbanization on chemical and biochemical properties of soils in touristy town—Zakopane—was investigated. The concentration of heavy metals, nutrients, soil organic matter (SOM), dehydrogenase (DHA), invertase (IA) and urease (Ure) activities in soils from the town centre and out of the town centre was compared with the respective values of adjacent soils in protected areas (TNP). In order to evaluate a degree of contamination and risks of degradation enrichment factor (EF), ecological risk index (RI), Nemerov Pollution Index (PINemerov) as well as enzyme activity index (EAI) were calculated. Soils in the centre of Zakopane were polluted with Zn, Pb, Cd and Cu in a moderate degree when those of skiing areas were polluted with Pb and Cd in a high degree. Strong positive correlation between these metals and negative correlation between them and a distance from the main roundabout in town indicated their anthropogenic origin. Soils of both locations were also enriched in P, but depleted in SOM when compared to TNP soils. Soils of touristy areas (out of the centre) were additionally enriched in N. Activity of studied enzymes was also lowered in soils of Zakopane when compared to soils of TNP. Pollution indices, RI, PINemerov as well as EAI, indicated that soils of Zakopane are at risk of degradation. Soils of touristy areas are under stronger negative impact than soils of the centre because of the cumulative effect of transport of heavy metals from the city centre, pollution by skiing machinery and melting water from the artificial snow.