Reclamation of Post-Technological Landscapes: International Experience

Introduction. Anthropogenic activities cause large-scale environmental problems. The growing volumes of toxic emissions contribute to soil, water, and air pollution, thus posing a serious threat to all living systems and the global ecosystem. New reclamation methods are a relevant research topic as they help to restore and preserve ecosystems. Study objects and methods. The research covered sixteen years of scientific publications from PubMed of the National Center for Biotechnology Information (USA), Elsevier (Scopus, ScienceDirect), Web of Science, and the national electronic library service eLibrary.ru. Results and discussion. The authors reviewed various scientific publications to define the main technogenic objects that have a toxic effect on biota. Soil is more vulnerable to destructive effects, and mining wastes are responsible for the largest share of technogenically disturbed objects. Pollutants include many compounds, such as heavy metals, hydrocarbons, sulfur compounds, acids, etc. Reclamation technologies reduce the man-induced impact on the environment, e.g. pollutants can be completely or partially destroyed, processed into non-toxic products, completely removed, stabilized into less toxic forms, etc. This review provides information on the main methods of reclamation of disturbed soils and substantiates the prospect of developing integrated reclamation technologies. Conclusion. The present review featured the main pollutants of anthropogenic origin and the traditional soil reclamation methods. The most prospective new technologies of soil reclamation appeared to be a combination of such biological methods as phytoremediation, bioaugmentation, and biostimulation.

Soil Fabric and Transitional Behavior in Completely Decomposed Granite: An Example of Well-Graded Soil

Unlike sedimentary soils, limited studies have dealt with completely decomposed granite (CDG) soils, even though they are plentiful and used extensively in several engineering applications. In this paper, a set of triaxial compression tests have been conducted on well-graded intact and disturbed CDG soils to study the impact of the fabric on soil behavior. The soil behavior was robustly affected by the soil fabric and its mineral composition. The intact soil showed multiple parallel compression lines, while a unique isotropic compression line was present in the case of disturbed soil. Both the intact and disturbed soils showed unique critical state lines (CSL) in both the e-log p′ and q-p′ spaces. The intact soil showed behavior unlike other transitional soils that have both distinct isotropic compression lines ICLs and CSLs. The gradient of the unique ICL of the disturbed soil was much more than that of the parallel compression lines of the intact soil. In the intact soil, the slope of the unique CSL (M) in the q-p′ space was higher than that of the disturbed soil. The isotropic response was present for both the intact and disturbed soils after erasing the inherited anisotropy as the stress increased with irrecoverable volumetric change. Soil fabric is considered the dominant factor in the transitional behavior and such a mode of soil behavior is no longer restricted to gap-graded soil as previously thought.

Ecological and agrochemical assessment of the state of technogenically disturbed soil cover of the steppe zone of the Volga region

The anthropogenic impact on the biosphere every year leads to the depletion of all natural resources, including soil, which leads humanity to an ecological catastrophe. We have carried out work on the assessment of recultivation of the soil disturbed during the technical re-equipment works. It was revealed that in the soil areas located in the corridor of the passage of communications, due to the constant work on the repair, dismantling and construction of the routes of the corridor of their passage, the natural soil cover is not preserved, and in some places completely disappears, as well as there is mixing of soil layers and destruction of the natural soil cover. Keywords: URBANIZATION, TECHNOGENICALLY DISTURBED SOILS, MEADOW-CHERNOZEM SOILS, SOIL FERTILITY

Setaria parviflora (knotroot foxtail).

S. parviflora is a variable, self-compatible, rhizomatous, C4 plant with a short lived seed bank, commonly regarded as an agricultural weed both in its native and introduced range (Rabinowitz and Rapp, 1981; Pensiero, 1999; Mollard et al., 2007; Mollard and Insausti, 2011; Randall, 2012). It often colonizes cultivated and disturbed soils or waste places including seasonally wet sites and salt marshes (Hubbard, 1954; Leithead et al., 1971; Pott and Pott, 2004; Edgar and Connor, 2010). It can contaminate wool (Ryves et al., 1996), seed crops, especially those of grasses such as dryland rice, lawn seed and Bahia grass (Paspalum notatum) (Silveira Filho and Aquino, 1983; Wehtje et al., 2008; Seed Regulatory and Testing Branch, 2011) and degrade and dominate sod and pastures (including alfalfa), lowering hay quality, a problem because it can cause lesions in livestock (Murphy et al., 1992; Arregui et al., 2001; Muller and Via, 2012). Land infested with it might be considered to have lower value because of poor pasture. It is regarded as a member of the alien flora of Chile (Ugarte et al., 2011).

Efficiency of dust control products in suppression of wind-induced dust emission from soils

<p>Surfaces of disturbed soils are subjected to dust PM10 (particulate matter < 10 µm) emission by wind process regardless of human activities such as vehicles (wheels) traveling. However, there is little quantitative information on the efficiency of dust control products in suppression of wind-induced dust emission. The study aimed to fill this clear gap using wind-tunnel experiments under laboratory and field conditions. Diverse dust control products of synthetic and organic polymers (Lignin, Resin, Bitumen, PVA, Brine) were tested. In the first stage, the products were tested under controlled-laboratory conditions. In the second stage, the products were tested in unpaved roads of an active quarry after the transportation of quarry-haul trucks in two time points after the product application. The results show that in most of the plots the dust emission increases with the wind velocity. PM10 fluxes from the road surface in each plot were calculated to determine the effectiveness of the dust control products. Some products significantly reduced the dust emission, especially the magnesium chloride brine. Additional experiments revealed that the brine can be applied with reduced amount than that of the recommended amount while keeping on low dust emission.</p>

Microbiological description of self-overgrowing spoil heaps and sand quarries in Nordwest Russia

<p>Self-overgrowing recovery of disturbed soils is one of important processes in reclamation of disturbed soils. Different types of anthropogenic disturbances followed by variety of soil types and their genesis leads to different bacterial communities, envolved in reclamation processes. Here we describe regional self-overgrowing soils in two location (Novgorod region, Northwest Russia). We analyse top level of industrial disturbed soils after coil mining (spoil tips with extremely low pH, and <span>overburden </span>soil) and sand quarry dumps followed by local undisturbed soils.</p><p>We perform 16s amplicone sequencind (v4-region) by Illumina MiSEQ and chemical routine analysis (pH, C, N and other). We provide alpha- and beta-diversity analysis, followed by CCA and analysis of differential abundance of taxa.</p><p>Sand quarry dumps and regional soils looks common on phyla level, and represent common soil phyla like <em>Proteobacteria</em>, <em>Actinobacteria</em> and <em>Verrucomicrobia</em>. Alpha-diversity metrics aslo are similar, despite difference in beta-diversity. O<span>verburden soil and soil from spot tips, by contrast, is very different even in phylum level. Main intermediants here are <em>Actinobacteria</em>, <em>Chloroflexi</em> и <em>Nitrospirae</em>. Also they show extremely low alpha-diversity metrics.</span></p><p><span>This work was supported by RSF 17-16-01030, «Dynamics of soil biota in chronoseries of post-technogenic landscapes: analysis of soil-ecological efficiency of ecosystem restoration processes»</span></p>

Assessment of the Effect of Organic Matter on the Retention of Lead in Perturbed Soils.

Four types of soils were prepared with humified matter, bentonite, kaolin and inert matter, in order to control the organic matter (OM) content in the evaluation of retention of lead (II) by adsorption in disturbed soils with the possibility of being contaminated. The results indicated that retention capacity of Pb+2 increases as organic matter increases, however, this retention is not proportional to the organic matter increment. An increase of 10 units in the concentration of the background solution results in a decrease in the retention capacity of 50%. The outcomes also indicated that lead (II) adsorption is successfully explained by the Langmuir model and the adsorption kinetics fitted well to the Ho pseudo second order model. The thermodynamic values of the Gibbs free energy indicated that it was a spontaneous process and the energy of the process suggests a retention mechanism by ion exchange. A soil with high content of organic matter does not guarantee high retention of lead, even more so when the adsorption mechanism is given by ion exchange.