scholarly journals Microplastic Contamination in Soils: A Review from Geotechnical Engineering View

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4129
Author(s):  
Mehmet Murat Monkul ◽  
Hakkı O. Özhan
Keyword(s):  
Geotechnical Engineering ◽  
Animal Health ◽  
Soil Improvement ◽  
Freshwater Ecosystems ◽  
Local Source ◽  
Solid Waste Disposal ◽  
Environmental Chemical ◽  
Geotechnical Structures ◽  
Geotechnical Design

Microplastic contamination is a growing threat to marine and freshwater ecosystems, agricultural production, groundwater, plant growth and even human and animal health. Disintegration of plastic products due to mainly biochemical or physical activities leads to the formation and existence of microplastics in significant amounts, not only in marine and freshwater environments but also in soils. There are several valuable studies on microplastics in soils, which have typically focused on environmental, chemical, agricultural and health aspects. However, there is also a need for the geotechnical engineering perspective on microplastic contamination in soils. In this review paper, first, degradation, existence and persistence of microplastics in soils are assessed by considering various studies. Then, the potential role of solid waste disposal facilities as a source for microplastics is discussed by considering their geotechnical design and addressing the risk for the migration of microplastics from landfills to soils and other environments. Even though landfills are considered as one of the main geotechnical structures that contribute to the formation of considerably high amounts of microplastics and their contamination in soils, some other geotechnical engineering applications (i.e., soil improvement with tirechips, forming engineering fills with dredged sediments, soil improvement with synthetic polymer-based fibers, polystyrene based lightweight fill applications), as potential local source for microplastics, are also mentioned. Finally, the importance of geotechnical engineering as a mitigation tool for microplastics is emphasized and several important research topics involving geotechnical engineering are suggested.

scholarly journals Molecular Methods as Potential Tools in Ecohydrological Studies on Emerging Contaminants in Freshwater Ecosystems

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2962
Author(s):  
Elzbieta Mierzejewska ◽  
Magdalena Urbaniak
Keyword(s):  
Emerging Contaminants ◽  
Animal Health ◽  
Freshwater Ecosystems ◽  
Molecular Methods ◽  
Stress Factors ◽  
Ecotoxicological Assessment ◽  
Relationship Analysis ◽  
Multiple Indicator ◽  
Number Of Publications

Contaminants of emerging concern (CECs) present a threat to the functioning of freshwater ecosystems. Their spread in the environment can affect both plant and animal health. Ecohydrology serves as a solution for assessment approaches (i.e., threat identification, ecotoxicological assessment, and cause–effect relationship analysis) and solution approaches (i.e., the elaboration of nature-based solutions: NBSs), mitigating the toxic effect of CECs. However, the wide array of potential molecular analyses are not fully exploited in ecohydrological research. Although the number of publications considering the application of molecular tools in freshwater studies has been steadily growing, no paper has reviewed the most prominent studies on the potential use of molecular technologies in ecohydrology. Therefore, the present article examines the role of molecular methods and novel omics technologies as essential tools in the ecohydrological approach to CECs management in freshwater ecosystems. It considers DNA, RNA and protein-level analyses intended to provide an overall view on the response of organisms to stress factors. This is compliant with the principles of ecohydrology, which emphasize the importance of multiple indicator measurements and correlation analysis in order to determine the effects of contaminants, their interaction with other environmental factors and their removal using NBS in freshwater ecosystems.

scholarly journals Wood Pastures: A Transitional Habitat between Forests and Pastures for Dung Beetle Assemblages

Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 25
Author(s):  
László Somay ◽  
Viktor Szigeti ◽  
Gergely Boros ◽  
Réka Ádám ◽  
András Báldi
Keyword(s):  
Functional Group ◽  
Animal Health ◽  
Habitat Type ◽  
Dung Beetle ◽  
Dung Beetles ◽  
Livestock Grazing ◽  
Pitfall Traps ◽  
Assemblage Composition ◽  
Beetle Assemblages

Wood pastures are home to a variety of species, including the dung beetle. Dung beetles are an important functional group in decomposition. Specifically, in terms of livestock manure, they not only contribute to nutrient cycling but are key players in supporting human and animal health. Dung beetles, however, are declining in population, and urgent recommendations are needed to reverse this trend. Recommendations need to be based on solid evidence and specific habitats. Herein, we aimed to investigate the role of an intermediate habitat type between forests and pastures. Wood pastures are key areas for dung beetle conservation. For this reason, we compared dung beetle assemblages among forests, wood pastures, and grasslands. We complemented this with studies on the effects of dung type and season at three Hungarian locations. Pitfall traps baited with cattle, sheep, or horse dung were used in forests, wood pastures, and pasture habitats in spring, summer, and autumn. Dung beetle assemblages of wood pastures showed transient characteristics between forests and pastures regarding their abundance, species richness, Shannon diversity, assemblage composition, and indicator species. We identified a strong effect of season and a weak of dung type. Assemblage composition proved to be the most sensitive measure of differences among habitats. The conservation of dung beetles, and the decomposition services they provide, need continuous livestock grazing to provide fresh dung, as well as the maintenance of wood pastures where dung beetle assemblages typical of forests and pastures can both survive.

scholarly journals The role of the geological uncertainty in a geotechnical design – A retrospective view of Freeway No. 3 Landslide in Northern Taiwan

2021 ◽  
pp. 106233
Author(s):  
Chih-Hsiang Yeh ◽  
Jia-Jyun Dong ◽  
Sara Khonevisan ◽  
C. Hsein Juang ◽  
Wen-Chao Huang ◽  
...  
Keyword(s):  
Geological Uncertainty ◽  
Retrospective View ◽  
Geotechnical Design ◽  
Northern Taiwan

Impact of some environmental chemical carcinogens on the incidence of hormone-dependent tumors and possible mechanisms of its realization (literary review)

2021 ◽  
Vol 99 (2) ◽  
pp. 44-55
Author(s):  
I.O. Chernychenko ◽  
◽  
N.V. Balenko ◽  
O.M. Lytvychenko ◽  
V.F. Babii ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Functional Organization ◽  
Endocrine System ◽  
Epidemiological Data ◽  
Environmental Carcinogens ◽  
Chemical Carcinogens ◽  
Environmental Chemical ◽  
Polycyclic Aromatic ◽  
Pollution Emissions

Objective: We determined the possible effects of priority chemical environmental carcinogens on the incidence of hormone-dependent tumors and the mechanisms of their effect on the basis of the analysis of literature data and our own research. Results: The performed analysis demonstrates the scanity of the research devoted to the study of chemical carcinogens which are concerned only with the class of polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene (BP), atmospheric pollution, emissions from vehicles, the cadmium heavy metal and products of smoking containing these substances. The connection with PAH (BP) and the development of breast, ovarian cancer, cadmium with the development of breast, endometrial, ovarian cancer in women and prostate cancer in men was established. Epidemiological data, combined with experimental ones, suggest a possible contribution of carcinogens into the increase of the incidence of hormone-dependent tumors. At the same time, mechanisms of action of PAH and cadmium on the development of hormone-dependent tumors are unclear. The accumulated experimental and epidemiological data allow us to conclude that the oncological danger of these carcinogens lies in the combination of genotoxic and hormone-mimetic properties; the main mechanisms, involved in the realization of the effect of BP and cadmium, are associated with changes and disorders at different levels of the structural and functional organization of the organism, including the endocrine system, which can lead to the development of tumors. The urgency of the problem of the incidence of hormone-dependent tumors and the potential role of the studied chemical carcinogens as pollutants of the environment of human functions indicate the need to take these circumstances into account when developing and implementing preventive measures.

scholarly journals Temporal and Spatial Coexistence of Archaeal and BacterialamoAGenes and Gene Transcripts in Lake Lucerne

Archaea ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Elisabeth W. Vissers ◽  
Flavio S. Anselmetti ◽  
Paul L. E. Bodelier ◽  
Gerard Muyzer ◽  
Christa Schleper ◽  
...  
Keyword(s):  
Temporal Distribution ◽  
Water Layer ◽  
Distribution Patterns ◽  
Freshwater Ecosystems ◽  
Ammonia Oxidizers ◽  
Lake Lucerne ◽  
Ammonia Oxidizing Archaea ◽  
Gene Transcripts ◽  
Temporal And Spatial

Despite their crucial role in the nitrogen cycle, freshwater ecosystems are relatively rarely studied for active ammonia oxidizers (AO). This study of Lake Lucerne determined the abundance of bothamoAgenes and gene transcripts of ammonia-oxidizing archaea (AOA) and bacteria (AOB) over a period of 16 months, shedding more light on the role of both AO in a deep, alpine lake environment. At the surface, at 42 m water depth, and in the water layer immediately above the sediment, AOA generally outnumbered AOB. However, in the surface water during summer stratification, when both AO were low in abundance, AOB were more numerous than AOA. Temporal distribution patterns of AOA and AOB were comparable. Higher abundances ofamoAgene transcripts were observed at the onset and end of summer stratification. In summer, archaealamoAgenes and transcripts correlated negatively with temperature and conductivity. Concentrations of ammonium and oxygen did not vary enough to explain theamoAgene and transcript dynamics. The observed herbivorous zooplankton may have caused a hidden flux of mineralized ammonium and a change in abundance of genes and transcripts. At the surface, AO might have been repressed during summer stratification due to nutrient limitation caused by active phytoplankton.

scholarly journals Geotechnical engineering behaviors of gellan gum biopolymer treated sand

2016 ◽  
Vol 53 (10) ◽  
pp. 1658-1670 ◽  
Author(s):  
Ilhan Chang ◽  
Jooyoung Im ◽  
Gye-Chun Cho
Keyword(s):  
Geotechnical Engineering ◽  
Friction Angle ◽  
Soil Improvement ◽  
Gellan Gum ◽  
Strengthening Effect ◽  
Calcite Precipitation ◽  
Unconfined Compression Test ◽  
Sand Particles ◽  
Engineering Practices ◽  
Moisture Conditions

Biological approaches have recently been explored as environmentally friendly alternatives to engineered soil methods in geotechnical engineering practices. The use of microbial induced calcite precipitation, reactive enzymes, and microbial polymers, such as biopolymers, in soil improvement has been studied by researchers around the world. In the present study, gellan gum, a microbial polysaccharide generally used in the food industry due to its hydrogel rheology, was used to strengthen sand. The effects of gellan gum on the geotechnical behaviors of cohesionless sand were evaluated through a series of experimental programs including an unconfined compression test, direct shear test, falling head permeability test, and scanning electron microscopy. The geotechnical properties (friction angle, cohesion, and unconfined compressive strength) of gellan gum–treated sands were determined based on varying moisture conditions: initial, dried, and re-submerged. Gellan gum has a distinct strengthening effect on cohesionless sands through artificial cohesion that varies with the moisture conditions. The strengthening effect of gellan gum on sand appears to be a result of the combination of enhanced bonding between unreactive sand particles and the agglomeration of sand particles through hydrogel condensation, in which the agglomerated sand particles behave as enlarged aggregates in soil.

scholarly journals Role of Research Methodology in Civil Engineering

2021 ◽  
Vol 9 (8) ◽  
pp. 1114-1117
Author(s):  
Shubhra Upadhyay
Keyword(s):  
Research Methodology ◽  
Structural Engineering ◽  
Civil Engineering ◽  
Geotechnical Engineering ◽  
Pushover Analysis ◽  
Research Problem ◽  
Research Field ◽  
Research Methodologies ◽  
Research Problems

Abstract: Research methodology is a method to consistently resolve the research problem. Research methodology may be termed as knowledge of science for studying how research is done empirically and theoretically. In this paper we have studied different steps that are usually taken by a researcher in studying his research problem of civil engineering along with the logic behind them. It is utmost important for the researcher to have the knowledge of the research techniques/method along with its methodology. Researchers also need to understand the presumptions underlying various techniques and they need to know the criteria by which they can decide that certain techniques and procedures will be applicable to certain problems and others will not. All this means that it is necessary for the researcher to design his methodology for his problem as the same may differ from problem to problem. Research methodologies are the need of hour due to modernization in research field of civil engineering. Nowadays only innovative research methods are adopted in branch of civil engineering like geotechnical engineering, geoenvironmental engineering, structural engineering, geo-mechanics etc so that best results are obtained from these methodologies. In this paper we are going to discuss role of some of the research methodologies used for research purposes in geotechnical engineering for respective research problems. Keywords: Research methodology, geotechnical engineering, pushover analysis, FLAC method, numerical method,

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