Ash Dump Research Articles

Communities of soil microarthropods (Acari, Collembola) at ash dumps of combined heat and power plant in conditions of varying degrees of conservation

Communities of soil microarthropods (Acari, Collembola) at ash dumps of combined heat and power plant in conditions of varying degrees of conservation

Coal-fired power plant and aquatic ecosystems

Coal industry remains one of the top electric energy sources in the world. Due to the substantial water demand, thermal power plants are built on the coasts of water bodies and rivers, which causes anthropogenic pressure on surface water. Aquatic ecosystems belong to the most vulnerable environmental compartments that reflect changes within the system itself and its watershed. The impact of coal-fired power industry on aquatic ecosystems is investigated on the example of the natural and anthropogenic complex of “Lake Kenon – TPP-1”. Lake Kenon is a natural freshwater lake of the Amur River basin. The results of research on the technoecosystem showed that a coal-fired power plant with incomplete coal combustion pollutes the reservoir. Chemicals enter Lake Kenon with emissions and effluents from TPP-1, ash dump leakages, and the flow of the Kadalinka River. Those affect both macro-and micro-component composition of the water and sediments of Lake Kenon with its hydrobionts accumulating toxic elements. To maintain the aquatic ecosystem of Lake Kenon, it is necessary to isolate surface watercourse of the ash dump leakage and control the flow of substances and energy in the lake and its watershed.

Soil microbiome after nine years of fly ash dump spontaneous revegetation

Fly ash dumps of thermal power stations have been increasing in area worldwide due to the growing demand for power. One of the cost-effective approaches for restoring such sites is spontaneous revegetation in those areas where adjacent indigenous ecosystems can supply seeds and living organisms. We assessed microbiome taxonomic diversity in a Technosol developed during nine years of spontaneous revegetation of the terminated fly ash pond of a thermal power station in Novosibirsk, Russia, in comparison with microbiome diversity in undisturbed Phaeozem under adjacent birch forest by using 16S (V3–V4) and ITS2 (ITS3–ITS4) amplicon sequencing with Illumina MiSeq. We identified 577 fungal and 5542 bacterial operational taxonomic units (OTUs); 95–99% of them were minor or rare species. The dominant OTUs were completely different in the studied soils. At the phylum level, the ultimate dominants were Ascomycota (84%) in the Technosol and Basidiomycota (89%) in the Phaeozem. Three phyla (Proteobacteria, Acidobacteria and Actinobacteria), together comprising more than a half of the bacteriobiome, prevailed in both soils; however, at the OTU level, soil-related differences were found for 31% of the OTUs. The Technosol bacteriobiome was less structured and more diverse compared to the mycobiome, displaying the same phylum-level structure and OTU-based α-biodiversity as in the adjacent mature soil. Our finding that few fungal and bacterial OTUs dominated in the soil microbiome, the majority being minor or rare members, implies that key ecosystem processes performed by soil microorganisms rely on a very limited taxonomic diversity, both in young and mature soils.

Natural forest colonisation and soil formation on ash dump in southern taiga

Abstract Ash dumps occupy significant areas around the world and make a negative influence on the environment. This effect is decreased by their natural colonisation determined by the bioclimatic conditions of the area. The purpose of the current study was to identify the structure of the forest communities and the initial stages of soil formation on the ash dump in southern taiga. This study was carried out on three sites in the forest phytocoenosis formed in the process of revegetation of the Verkhniy Tagil Power Station ash dump over 50 years, as well as on two background forest sites in the Middle Urals. Complex geobotanical and soil studies were carried out. The results of the study show that forest phytocoenoses with a predominance of hardwood species (Betula pendula Roth and Populus tremula L.) and a small admixture of coniferous species can form on the non-recultivated ash dump within 50 years in a boreal zone. In total, the studied mixed forest phytocoenoses are similar in composition to zonal secondary forests, but differ by having lower height and diameter of the stand, as well as herb–shrub layer coverage. Their species density and floristic richness are also lesser. The study proved that the process of soil formation is also proceeding according to the zonal type in the ash substrate under forest communities. The results of the study can be applied to justifying the forecasts of ecosystem restoration on the technogenic substrate, as well as for the species selecting for their recultivation in the studied area and similar to it.

Spiders and harvestmen (Arachnida: Aranei, Opiliones) of the revegetating ash dumps of a combined heat and power plant in Novosibirsk (Russia, West Siberia)

Spiders and harvestmen (Arachnida: Aranei, Opiliones) of the revegetating ash dumps of a combined heat and power plant in Novosibirsk (Russia, West Siberia)

Functional response of Betula species to edaphic and nutrient stress during restoration of fly ash deposits in the Middle Urals (Russia).

We studied the impact of fly ash produced by the thermal power station in the Middle Urals (Russia) on functional traits of two Betula species naturally colonizing ash dump lagoons. The main limiting factors for tree growth on fly ash deposits were nitrogen deficiency, high alkalinity, and unfavorable mechanical composition of substrate. Leaf area ratio (LAR) and leaf mass ratio (LMR) per tree, leaf area (LA), leaf shape coefficient (LSh), leaf thickness (LT), leaf mass per area (LMA), photosynthesis (Amax) and transpiration rates, chlorophyll (Chl), carotenoid (Car), and nitrogen (N) content were measured in Betula pendula Roth and Betula pubescens Ehrh. growing on the ash dump and in the forest near the dump. Both Betula species showed similar functional response to adverse conditions of the fly ash. We found a 1.5-2-fold increase in LAR and LMR in trees growing on fly ash deposits compared with trees in the forest. In both species, the most significant differences across leaf morphological traits were shown for LT. Higher LT provided an increase in Chl and N content per leaf area that caused the rise in Amax and photosynthetic water use efficiency in the trees on the ash deposit. At the same time, Betula species preserved interspecific differences in values of LA and LT which were larger in B. pubescens whiles B. pendula differed by higher LSh. We concluded that the increase in assimilation activity at both whole-plant and leaf levels provides plant adjustment to edaphic and nutrient stress that allow Betula species to colonize technogenic substrates as fly ash deposits.

Sustainable sludge management - its use for remediation of degraded lands

The sludge resulted from the urban wastewater treatment plants, can be used, from a circular economy, as a fertilizer for agricultural and degraded lands, for horticulture and forestry. This paper aims to propose an alternative for the use of this type of sludge in a sustainable way, with a low impact on the environment. The study consisted of experiments done to recover the stabilized sludge from the urban wastewater treatment plants in the process of degraded land rehabilitation, using the energetic willow, Salix sp. The experimental results showed that the use of stabilized sludge as fertilizer for naturally and anthropogenic degraded lands determined the improvement of nutritional characteristics of the lands cultivated with Salix sp., and allowed the growth, development, and maintenance of this plant. Taking into consideration the characteristics of the cultures and the quantities of metals accumulated by Salix sp., it can be concluded that these plants were adapted to the environmental conditions and the substrate toxically composition. The results obtained on two degraded lands indicate that Salix sp. can be used for its introduction in the economic circuit, both for salty soils and ash dumps.

Platanthera bifolia (L.) Rich. on industrial dumps in the Middle Urals

We studied cenopopulations of Platanthera bifolia on industrial dumps in the Middle Urals (the southerndump of the Veselovsky brown coal deposit, the ash dump of the Verkhnetagil State District Power Plant). The spatial,age, morphological structure and features of mycorrhiza formation of this species on disturbed lands were studied. Thecenopopulations of P. bifolia growing on industrial dumps of the Veselovsky brown coal deposit, VSDPP ash dump andin the natural forest phytocenosis of the forest park are normal, incomplete, with a predominant generative state in theage spectrum. It was revealed, that P. bifolia individuals from industrial dumps correspond to the sizes of individualsfrom natural habitats according to most biometric indicators. The size of the root system is significantly affected by thecharacteristics of the substrate (low fertility, rockiness).

Morphology and biology of Bromopsis inermis (Leyss.) Holub in culture conditions at the ash dump of the Sredneuralskaya State District Power Station

The article presents the results of Bromopsis inermis (Leyss.) Holub study under cultivation conditionsat the ash dump of the Sredneuralskaya state regional power station (SUGRES) located in the taiga zone. Studies haveshown that rehabilitation activities at the ash dump of SUGRES created favorable conditions for the growth of plants.Bromopsis inermis is the most promising for growing on ashes with the application of peat. The biological feature of thisspecies is the development of a powerful root system with a sufficient content of mineral nutrition elements in the peatand intensive shoot formation, which contributed to its active vegetative renewal and the creation of long-lasting (morethan 20 years) productive culture phytocenoses.

Metal remediation potential of naturally occurring plants growing on barren fly ash dumps.

The present study aimed to elucidate the remediation potential of visibly dominant, naturally growing plants obtained from an early colonized fly ash dump near a coal-based thermal power station. The vegetation comprised of grasses like Saccharum spontaneum L., Cynodon dactylon (L.) Pers., herbs such as Tephrosia purpurea (L.) Pers., Sida rhombifolia L., Dysphania ambrosioides (L.) Mosyakin & Clemants, Chromolaena odorata (L.) King & H.E. Robins along with tree saplings Butea monosperma (Lam.) Taub. The growth of the vegetation improved the N and P content of the ash. Average metal concentrations (mgkg-1) in the ash samples and plants were in order Mn (345.1) > Zn (63.7) > Ni (29.3) > Cu (16.8) > Cr (9.9) > Pb (1.7) > Cd (0.41) and Cr (58.58) > Zn (52.74) > Mn (39.09) > Cu (10.71) > Ni (7.45) > Pb (5.52) > Cd (0.14), respectively. The plants showed fly ash dump phytostabilization potential and accumulated Cr (80.19-178.11mgkg-1) above maximum allowable concentrations for plant tissues. Positive correlations were also obtained for metal concentration in plant roots versus fly ash. Saccharum spontaneum showed highest biomass and is the most efficient plant which can be used for the restoration of ash dumps.

Experiences on establishment of Scots pine (Pinus sylvestris L.) plantation in ash dump sites of Reftinskaya HPES, Russia

Since the middle of the last century in the Urals of Russia there has been a problem of environmental pollution by man-made emissions. The purpose of this investigation has been to summarize the recultivation experience of Reftinskaya power plant ash dump. The station was put into operation in 1970 and it is the largest one in Russia. Specific feature of the used coal is high content of ash (47%). Daily consumption of coal in winter period constitutes 48 thousand tons. Yearly emissions of the station constitute 400 thousand tons. The main components of the emissions are sulphureous anhy-dride (up to 40%) solid stuff (up to 50%) and nitric oxides. The Scots pine (Pinus sylvestris L.) plantations on ash dumps have shown good adaptation and growth. The plantations have formed 143 m3/ha total volume at the age of 20 in 1st site index of the recultivation site of the ash dump with ash layer up to 7 m. Weakly alkaline reaction of the ash spread by wind promoted soil dioxidation that results in soil fertility increasing significantly on territory of adjacent stands. Recultivation process includes two main stages which are ash dump surface covering with 25-40 cm soil layer, planting with 2-year old Scots pine (Pinus sylvestris L.) seedling.

Black locust stand structure on the sterile dump in the middle basin of Jiu River (Romania)

Introduced in 1750 as an ornamental tree and then in 1852 as a forest tree species, black locust occupied nowadays 250,000 ha in Romania. The tree species is important for its wood (lumber, poles, firewood, etc.), its honey-related production as well as its environmental role (afforestation of sand dunes and sterile dumps). One of the most important activities in the middle basin of Jiu River is coal mining. After 1956 this activity has developed very quickly and two power plants were built in Rovinari and Turceni. As a result, sterile dumps and coal ash dumps have established so it was necessary to restore the area by afforestation. This activity started with the sterile dump Viaduct Rovinari, using Austrian pine and black locust, and continued with others such as Cocoreni and Moi. The most used tree species for ecological restoration was black locust. In order to express the stand structure, diameter at breast height (DBH), total height (H) and crown diameter were measured. The soil analysis were performed and showed differences in the content of heavy metals and radionuclides for both location. The study revealed positive correlations between DBH and H, a stronger one for Moi plantation. Our research highlights the capacity of black locust to establish and grow under very difficult site conditions.

Physiological profiling of invasive plant species for ecological restoration of fly ash deposits

Extensive gaps in invasive plant species research in terms of ecosystem distribution and impact are major barriers faced by global decision making bodies for scientific management of plant species invasions of native flora. Effective strategies need to be worked out which would enable simultaneous management and the use of invasive plant species for ecosystem restoration. For evaluating the photosynthetic potential of invasive plant species in restoration of degraded areas, exhaustive in situ leaf gas exchange and leaf chlorophyll fluorescence were undertaken on four plants found naturally colonizing on the fly ash deposits. The four invasive species screened for their physiological tolerances towards microclimatic and edaphic stresses in harsh fly ash deposits were: Typha latifolia, Saccharum spontaneum, Prosopis juliflora, and Ipomea carnea. Saccharum spontaneum was found to be most efficient in sequestering CO2 emissions which were reflected in its maximum net photosynthetic rate (A, 29.29 ± 0.46 μmolCO2 m−2s−1) and higher below ground biomass. Maximum water use efficiency (WUE) was observed in S. spontaneum (9.3 ± 0.5 mmolCO2 molH2O−1) among all the species owing to high carboxylation, the lowest transpiration rate (E, 3.15 ± 0.13 mmolH2Om−2s−1) and stomatal conductance (gs, 0.2 ± 0.004 molH2Om−2s−1) values supporting it’s dense growth throughout the fly ash dumps in contrast to other three species. The study provides insights into the successful use of invasive plant species for their effective management and phytorestoration of fly ash dumps by transforming them into net carbon sinks which otherwise lack any native flora.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ЗОЛЬНЫХ МИНЕРАЛЬНЫХ ДОБАВОК НА ПОКАЗАТЕЛИ КАЧЕСТВА ЦЕМЕНТА

The report presents the results of a study of the possibility of replacing the mineral additive ‒ fly ash, formed during the combustion of solid fuel, with ash from ash dumps. It is shown that such a replacement is quite possible and does not significantly affect the quality of cement.

The effect of the substrate on the anatomical and morphophysiological parameters of Pimpinella saxifraga L. on the ash dump

The structural and functional features of the species Pimpinella saxifraga L., which grows in the ash dumpof the Verkhnetagil State District Power Station, were investigated, compared with the natural habitat. We studied suchindicators as biomass distribution, parameters of the leaf mesostructure (the area and thickness of the leaf blade, thethickness of the mesophyll and epidermis, the size of cells and chloroplasts and their number per unit area of the leaf, thenumber of chloroplasts in cell, etc.). Pimpinella saxifraga, growing on the ash dump, showed a change in morphologicalparameters, compared with the control: a decrease in the weight of the roots, an increase in the weight of the aerialorgans, a decrease in the area of the leaf blade and the thickness of the leaf. The structural adaptation of mesophyll toenvironmental conditions consisted in changing the number and size of cells without changing the parameters of theplastid apparatus (number and size of chloroplasts). The properties of the substrate did not significantly influence on theinternal leaf area. Such adaptive changes allows this species to grow on technogenic substrates.

ЕКОЛОГІЧНА НЕБЕЗПЕКА ТЕХНОГЕННОГО ЗАБРУДНЕННЯ ГРУНТІВ ВАЖКИМИ МЕТАЛАМИ ДЛЯ ТЕРИТОРІЙ ВПЛИВУ БУРШТИНСЬКОЇ ТЕС

У статті проаналізовано проблеми забруднення довкілля та виявлено ризики для здоров´я населення й навколишнього середовища, що зумовлені роботою вугільних теплових електричних станцій. Автори виявили фактори, які чинять екотоксикологічний вплив на окремі компоненти довкілля в зонах впливу Бурштинської ТЕС. У результаті аналізу визначено, що основними джерелами забруднення навколишнього середовища територій є викиди та відходи, які утворюються під час спалювання кам'яного вугілля. Виявлено, що причиною збільшення показників смертності населення в зонах техногенного впливу ТЕС є викиди SOx; NOx; CO та дрібнодисперсні часточки золи. Наведено розрахункові значення середніх за рік шкідливих викидів ТЕС та можливі наслідки їх впливу на людей, які мешкають в зонах ризику. З’ясовано, що особливо небезпечний та токсичний вплив на довкілля чинять важкі метали, які є складовими компонентами часточок золи, що містяться у викидах та відходах. Для дослідження ґрунтів на вміст важких металів було обрано ділянки з різнотрав´ям, зораний шар ґрунту та ґрунт під деревами. Проби ґрунту відбиралися на відстані 1,5-2 км від ТЕС. Методами спектрального і атомно-абсорбційного аналізу досліджено вміст валових та рухомих сполук важких металів, закономірності їх розподілу і форми знаходження у ґрунтах й золовідвалах. Встановлено, що навколо джерела забруднення утворюються ділянки з ґрунтами, які містять Со, Cu, Cr, Ni, Cd, Pb, Zn, Mn. За результатами аналізу визначено, що забруднення територій навколо ТЕС відбувається нерівномірно. У дослідних зразках ґрунту, виявлено підвищений вміст важких металів. На ділянках зораних шарів грунту та під деревами визначено перевищення валових концентрацій кадмію (Cd) та (Pb), що дозволило зробити висновок про непридатність для вирощування агрокультур для зазначених територій. На ґрунті під деревами та на ділянках з різнотрав´ям вміст Cu, Cr, Ni, Cd не перевищує значень ГДК. Рекомендовано заходи підвищення рівня екологічної безпеки вугільних станцій.

Geochemical fractionation of hazardous elements in fresh and drilled weathered South African coal fly ashes.

The chemical reactions of dry-disposed ash dump, ingressed oxygen, carbon dioxide, and infiltrating rainwater affect mineralogical transformation, redistribution, and migration of chemical species. Composite samples of weathered coal fly ash taken at various depths and fresh coal fly ash were examined using organic petrographic, X-ray diffraction, X-ray fluorescence techniques, and successive extraction procedures. Results obtained show relative enrichment of glass, Al-Fe-oxides, calcite, and tridymite in the weathered CFA, but the fresh CFA is enriched in mullite, inertinite, maghemite, and ettringite. The enrichment of the weathered CFA in amorphous glass suggests higher reactivity when compared to fresh CFA. The evident depletion of soluble oxides in the weathered CFA is attributed to flushing of the soluble salts by percolating rainwater. Comparative enrichment of examined elements in water-soluble, exchangeable, reducible, and residual fractions of the weathered CFA is partly due to the slow release of adsorbed chemical species from the alumina-silicate matrix and diffusion from the deeper sections of the particles of coal fly ash. Sodium and potassium show enrichment in the oxidisable fraction of fresh CFA. The estimated mobility factor indicates mobility for Ca, Mg, Na, Se, Mo, and Sb and K, Sr, V, Cu, Cr, Se, and B in fresh and weathered CFAs, respectively.

Исследование эффективности методов снижения пылеобразования на золошлакоотвалах

This research was aimed at analysing ash and slag dumps as objects of negative impact on atmospheric air, as well as at studying available methods for dust suppression. The existing ash and slag dump of the Novo-Irkutskaya combined heat and power plant, located in the forest park area between the cities of Irkutsk and Shelekhov, was considered. The territory adjacent to the ash dump is represented by forests in its south-eastern, eastern, and south-western parts, while the north-eastern part – by farmland. The operation of the ash and slag dump of the Novo-Irkutskaya thermal power plant leads to an increased level of atmospheric air pollution in the nearby residential area, which is situated outside the sanitary protection zone. This indicates the need to develop and implement measures to reduce dust formation from the surface of the ash and slag dump. In order to identify the most effective dust reduction method, it is important to calculate changes in emissions depending on the method used. To this end, we approximated the effective area of the dusting surface and the current ash particle outflow, which allowed determination of the surface concentrations of pollutants outside the ash dump area. Using a calculation method, we proved that the minimum rate of ash particle removal is observed when the water level in the nearby clarification pond is increased. It should be noted that, in addition to environmental aspects, economic factors should also be taken into account when developing environmental measures

Taxonomic diversity of bacterial assemblage in technosol of the revegetating fly ash dump

Background. The aim of the study was to assess the composition and structure of bacterial assemblages by estimating 16S rRNA gene sequences diversity in a young Technosol, developing on a revegetating fly ash dump. Location and place of the study. Two soils were chosen for the study in the environs of the thermoelectric power station No.5 in Novosibirsk region: 1) nine years old Technosol (54°59' NL, 83°03' EL), developing on the spontaneously revegetating fly ash dump, and 2) Phaeozem under undisturbed white birch forest (55°00' NL, 83°04' EL). Soils were sampled from the 0-5 cm layer as three individual replicates each. Materials and methods. The total DNA extracted from soil samples was used as a matrix for PCR amplification using V-3-V4 primers for 16S rRNA genes. The obtained amplicons were sequenced on Illumina MiSeq platform in the Genomics Core Facility of the Institute of Chemical Biology and Fundamental Medicine SB RAS (Novosibirsk, Russia). Descriptive statistics and principal components analysis were used to analyze and present the data. Results. Overall 4887 different operational taxonomic units (OTUs) were found at the 97% similarity level; the OTUs were ascribed to 306 genera, 212 families, 123 orders, 84 classes and 32 phyla of bacteria domain. At the phylum level bacterial assemblages in both soils were dominated by Proteobacteria, Acidobacteria and Actinobacteria, showing rather similar outline of the phyla relative abundance, confirming the direction of pedogenesis towards Phaeozem. Higher abundance of Chloroflexi a physiologically diverse phyla with aerobic and anaerobic thermophiles, anoxigenic phototrophs and anaerobes, able to respire organic halides, in the young Technosol complies with harsh edaphic conditions there. Although the relative abundance of Rhizobiales, Actinomycetales and unclassified Acidobacteria_Gp6 and Acidobacteria_Gp3 was found to be 1.5–2.4 times higher in the undisturbed Phaeozem, they also were predominating in the Technosol samples. The α-biodiversity indices, pertaining mostly to species/OTUs richness, i.e. Chao-1, OTUs number, Margalef, Fisher’s alpha, were higher in Phaeozem, whereas evenness and equitability were higher in Technosol. Both soils demonstrated similar Shanno indices, which were rather high (6.3). Conclusions. Nine years of spontaneous revegetation on the terminated fly ash dump of the thermoelectric power station resulted in the development of the Technosol, containing quite rich and diverse bacterial assemblage, which was rather close in structure at the phylum taxonomic level to the adjacent undisturbed Phaeozem. Overall the early stages of pedogenesis were dominated by specific bacterial assemblage (Chloroflexi, Xanthomonadales, Geobacter, Aciditerrimonas, Iamiaceae and some others), performing weathering of the pedogenic substrate, i.e. fly ash. The present of nitrificators (Nitrospira), denitrificators денитрификаторов (Reyranella) together with diazotrophs (Bradyrhizobium, Rhizobiales) dominance evidences the establishment of the entire network of nitrogen transformation process already at the early stages of revegetation of the fly ash dump. Large percentage (17%) of Bacteria, the information about which ribosomal gene sequences is most likely absent in the respective data bases necessitates more detailed research into the soil microbiome on fly ash dumps.

Carbohydrate resources used by ants at ash dumps of combined heat and power plant at the initial stages of self-revegetation: preliminary data

Carbohydrate resources used by ants at ash dumps of combined heat and power plant at the initial stages of self-revegetation: preliminary data