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Impacts of anthropogenic pollutants on social group cohesion and individual sociability in fish: a systematic review and meta-analysis
2024
Tiddy, Izzy C. | Cortese, Daphne | Munson, Amelia | Blewett, Tamzin A. | Killen, Shaun S.
Anthropogenic pollutants are near-ubiquitous in aquatic systems. Aquatic animals such as fishes are subject to physiological stress induced by pollution present in aquatic systems, which can translate to changes in behaviour. Key adaptive behaviours such as shoaling and schooling may be subject to change as a result of physiological or metabolic stress or neurosensory impacts of pollution. This can result in fitness and ecological impacts such as increased predation risk and reduced foraging success. Here, we conducted a systematic metanalysis of the existing literature, comprising 165 studies, on the effects of anthropogenic pollution on sociability and group cohesion in fish species. Both organic (number of studies = 92, posterior mean (PM) = -0.483, p < 0.001) and inorganic (n = 24, PM = -0.697, p < 0.05) chemical pollutants, as well as light exposure (n = 21, PM = -3.176, p < 0.01) were found to reduce sociability. These pollutants did not reduce group cohesion, indicating that effects may be masked in group settings, though fewer studies were carried out on group cohesion and this is a key area for future research. Mixtures of chemical pollutants (n = 16) were found to reduce cohesion (PM = -45.42, p < 0.01), but increase sociability (PM = 46.00, p < 0.01). Evidence was found that fish may behaviourally acclimate to two forms of pollutant, namely mixed chemical pollutants (PM = -0.693, p < 0.05) and noise exposure (n = 22, PM = -4.059, p < 0.05). While aquatic systems are often subject to pollution from multiple sources and of multiple types, very few studies investigated the effects of multiple stressors concurrently. This review identifies trends in the existing literature, and highlights areas where further research is required in order to understand the behavioural and ecological impacts of anthropogenic pollutants in aquatic systems.
Afficher plus [+] Moins [-]Proteomic profiling reveals candidate markers for arsenic-induced skin keratosis
2016
Guo, Zhiling | Hu, Qin | Tian, Jijing | Yan, Li | Jing, Chuanyong | Xie, Heidi Qunhui | Bao, Wenjun | Rice, Robert H. | Zhao, Bin | Jiang, Guibin
Proteomics technology is an attractive biomarker candidate discovery tool that can be applied to study large sets of biological molecules. To identify novel biomarkers and molecular targets in arsenic-induced skin lesions, we have determined the protein profile of arsenic-affected human epidermal stratum corneum by shotgun proteomics. Samples of palm and foot sole from healthy subjects were analyzed, demonstrating similar protein patterns in palm and sole. Samples were collected from the palms of subjects with arsenic keratosis (lesional and adjacent non-lesional samples) and arsenic-exposed subjects without lesions (normal). Samples from non-exposed healthy individuals served as controls. We found that three proteins in arsenic-exposed lesional epidermis were consistently distinguishably expressed from the unaffected epidermis. One of these proteins, the cadherin-like transmembrane glycoprotein, desmoglein 1 (DSG1) was suppressed. Down-regulation of DSG1 may lead to reduced cell-cell adhesion, resulting in abnormal epidermal differentiation. The expression of keratin 6c (KRT6C) and fatty acid binding protein 5 (FABP5) were significantly increased. FABP5 is an intracellular lipid chaperone that plays an essential role in fatty acid metabolism in human skin. This raises a possibility that overexpression of FABP5 may affect the proliferation or differentiation of keratinocytes by altering lipid metabolism. KRT6C is a constituent of the cytoskeleton that maintains epidermal integrity and cohesion. Abnormal expression of KRT6C may affect its structural role in the epidermis. Our findings suggest an important approach for future studies of arsenic-mediated toxicity and skin cancer, where certain proteins may represent useful biomarkers of early diagnoses in high-risk populations and hopefully new treatment targets. Further studies are required to understand the biological role of these markers in skin pathogenesis from arsenic exposure.
Afficher plus [+] Moins [-]European seabass respond more strongly to noise exposure at night and habituate over repeated trials of sound exposure
2018
Neo, Y.Y. | Hubert, J. | Bolle, L.J. | Winter, H.V. | Slabbekoorn, H.
Aquatic animals live in an acoustic world, prone to pollution by globally increasing noise levels. Noisy human activities at sea have become widespread and continue day and night. The potential effects of this anthropogenic noise may be context-dependent and vary with the time of the day, depending on diel cycles in animal physiology and behaviour. Most studies to date have investigated behavioural changes within a single sound exposure session while the effects of, and habituation to, repeated exposures remain largely unknown. Here, we exposed groups of European seabass (Dicentrarchus labrax) in an outdoor pen to a series of eight repeated impulsive sound exposures over the course of two days at variable times of day/night. The baseline behaviour before sound exposure was different between day and night; with slower swimming and looser group cohesion observed at night. In response to sound exposures, groups increased their swimming speed, depth, and cohesion; with a greater effect during the night. Furthermore, groups also showed inter-trial habituation with respect to swimming depth. Our findings suggest that the impact of impulsive anthropogenic noise may be stronger at night than during the day for some fishes. Moreover, our results also suggest that habituation should be taken into account for sound impact assessments and potential mitigating measures.
Afficher plus [+] Moins [-]Effects of soil pollutants, biogeochemistry and microbiology on the distribution and composition of enchytraeid communities in urban and suburban holm oak stands
2013
Rota, Emilia | Caruso, Tancredi | Monaci, Fabrizio | Baldantoni, Daniela | De Nicola, Flavia | Iovieno, Paola | Bargagli, Roberto
Holm oaks form typical urban woodlands in the Mediterranean region. We aimed at characterizing the enchytraeid communities in these environments and searching for possible correlations with soil parameters, including the traffic contamination. Samples of litter and topsoil were collected at different spatial scales and seasons in Naples and Siena cities and in two suburban stands. Only the co-variation between pollution and other soil chemico-physical factors showed significant effects, whereas no direct effect of soil microbiology was detected. Some thermophilous Fridericia and Achaeta tolerate high concentrations of heavy metals and PAHs and their abundance was mainly determined by Ca bioavailability. Central-European mesophilous species increased significantly under more temperate environmental conditions. Different combinations of soil cohesiveness, grain size composition and moisture regime seem to select species of certain body sizes.
Afficher plus [+] Moins [-]Geotechnical properties of oil-polluted soil: a review
2022
Haghsheno, Hamed | Arabani, Mahyar
Soil polluted by oil and its derivatives is a critical environmental issue worldwide that jeopardizes ecological systems and causes geotechnical problems. This review paper focuses on the previous studies concerning the impacts of oil pollution on soil geotechnical properties. To this end, related academic literature on this topic was investigated and discussed. The findings of this study demonstrated that the addition of oil pollution in coarse-grained soils significantly reduces particle surface roughness. On the other hand, in fine-grained soils, it results in flocculation and secondary aggregation of clay particles, less aggregated and loose packing in the soil matrix, the formation of isometric pores, the formation of fissure-like pores, and an increase in mesoporosity. In general, it was found that the geotechnical properties of oil-polluted soils are mostly determined by the physicochemical and/or physical interactions between the soil and contaminant. Additionally, previous research has demonstrated that oil pollutants alter the geotechnical properties of cohesive and non-cohesive soils significantly, including the Atterberg limits, particle-size distribution, compaction behavior, unconfined compressive strength, friction angle, cohesion, hydraulic conductivity, and consolidation characteristics. However, no general pattern could be established for the majority of them. Besides, it was found that the degree of geotechnical property alteration of oil-polluted soil is strongly influenced by the soil type and features, as well as the quantity, type, and chemical composition of oil pollutants.
Afficher plus [+] Moins [-]Geo-environmental and geotechnical characterization of municipal solid waste from the selective collection in São Paulo city, Brazil
2022
Mondelli, Giulliana | Juarez, Mariana Barbosa | Jacinto, Christiane | de Oliveira, Márcio Adilson | Coelho, Lúcia Helena Gomes | Biancardi, Cinthia Bergamo | de Castro Faria, José Leonardo
This paper presents the characterization of municipal solid waste (MSW) randomly collected from two material recovery facilities in São Paulo city, before (input — recyclables) and after (output — rejects) the sorting processes. Geo-environmental and geotechnical tests were performed on shredded samples and a digestion method was applied to detect the metals As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn concentrations using an ICP OES. The objective was to assist future activities of integrated solid waste management and soil pollution. Results showed different particle sizes comparing the input (44.6%) and the output MSW (75.1%) passing through the 100-mm sieve. Organic matter and ash contents indicated the influence of inorganic carbon due to the plastics’ presence, with values varying between 6 and 13%. The pH values obtained were neutral and the electrical conductivity of the MSW rejects suggested a higher amount of ions, with values above 1000 µS/cm. Metals analyses show that Cd, Cu, Ni, Pb, and Zn are present in high concentrations, depending on the types of the materials. Standard Proctor compaction curves yielded maximum dry unit weight varying from 6.6 to 10.0 kN/m³ and optimum moisture contents from 20 to 42%. Cohesion ranged from 1.3 to 31.3 kPa and friction angle from 3.2 to 42.9°. The results are comparable with those obtained for other countries using different MSW treatments and contribute to the data basis for MSW from the selective collection, aiming the integrated solid waste management, serving for other countries that adopt MSW sorting and recycling.
Afficher plus [+] Moins [-]Urease production using corn steep liquor as a low-cost nutrient source by Sporosarcina pasteurii: biocementation and process optimization via artificial intelligence approaches
2022
Maleki-Kakelar, Mahdi | Azarhoosh, Mohammad Javad | Golmohammadi Senji, Sina | Aghaeinejad-Meybodi, Abbas
To commercialize the biocementation through microbial induced carbonate precipitation (MICP), the current study aimed at replacing the costly standard nutrient medium with corn steep liquor (CSL), an inexpensive bio-industrial by-product, on the production of urease enzyme by Sporosarcina pasteurii (PTC 1845). Multiple linear regression (MLR) in linear and quadratic forms, adaptive neuro-fuzzy inference system (ANFIS), and genetic programming (GP) were used for modeling of process based on the experimental data for improving the urease activity (UA). In these models, CSL concentration, urea concentration, nickel supplementation, and incubation time as independent variables and UA as target function were considered. The results of modeling showed that the GP model had the best performance to predict the extent of urease, compared to other ones. The GP model had higher R² as well as lower RSME in comparison with the models derived from ANFIS and MLR. Under the optimum conditions optimized by GP method, the maximum UA value of 3.6 Mm min–¹ was also obtained for 5%v/v CSL concentration, 4.5 g L–¹ urea concentration, 0 μM nickel supplementation, and 60 h incubation time. A good agreement between the outputs of GP model for the optimal UA and experimental result was obtained. Finally, a series of laboratory experiments were undertaken to evaluate the influence of biological cementation on the strengthening behavior of treated soil. The maximum shear stress improvement between bio-treated and untreated samples was 292% under normal stress of 55.5 kN as a result of an increase in interparticle cohesion parameters.
Afficher plus [+] Moins [-]Strength characteristics of geosynthetic reinforced mechanically biologically treated waste by triaxial test
2022
Wang, Min | Zhang, Zhenying | Xu, Hui | Nie, Chengyu | Wang, Bang | Huang, Menghe | Li, Tuo
The reinforcement strength characteristics of mechanically biologically treated (MBT) waste were studied by conducting consolidated undrained triaxial tests with MBT waste collected from the Hangzhou Tianziling landfill pilot project. In the tests, the effects of the reinforcement material used (geomembrane, geotextile, and geogrid) and the number of reinforcement layers used (one, two, and three layers) were assessed. The results showed the following: (1) even through the axial strain increases up to 25%, the deviator stress of MBT waste could not reach a well-defined peak; (2) the reinforcement effect is related to the type of reinforcement material, with geogrid exhibiting the best reinforcement effect and geomembrane the worst; (3) the strength ratio of reinforced MBT waste is related to the confining pressure and the number of reinforcement layers, with a greater strength ratio in the MBT waste attained with a lower confining pressure in a logarithmic relationship and a greater strength ratio in the MBT waste attained with a greater number of reinforcement layers in a linear relationship; (4) the reinforced MBT waste shear strength parameter variation ranges for the cohesion (c), internal friction angle (φ), effective cohesion (c′), and effective internal friction angle (φ′) are 3.92–13.69 kPa, 19°–29°, 10.10–27.94 kPa, and 24°–45°, respectively; and (5) the deviations in the test values from the apparent cohesion method and the semi-empirical formula method are less than 15%, indicating that these two theories of reinforced sand can also be applied to MBT waste. The results of this study are useful as a baseline reference for the stability assessment of MBT waste landfills.
Afficher plus [+] Moins [-]Research on direct shear strength characteristics of mechanically biologically treated waste
2021
Zhang, Zhenying | Zhang, Jiahe | Wang, Qiaona | Wang, Min | Nie, Chengyu
Mechanically and biologically treated (MBT) waste has significant characteristics such as high stability and low moisture content, which can reduce water, soil, and gas pollution in subsequent treatments. This pre-treatment method is environmentally friendly and sustainable and has become a popular research topic in the field of environmental geotechnical engineering. Using a direct shear test apparatus and five shearing rates (0.25, 1, 5, 10, and 20 mm/min), the shear strength characteristics of MBT waste at the Hangzhou Tianziling Landfill were studied. The results indicate the following: (1) With the increase in horizontal shear displacement, the shear stress of MBT waste gradually increases without a peak stress phenomenon, which is a displacement hardening curve; (2) the shear strength increases with an increase in the shearing displacement rate, and the sensitivity coefficient is 0.64–2.66; (3) a shear strength, shearing rate, and normal stress correlation model is established, and the model has a high degree of fit with the overall experimental data; (4) cohesion (c), internal friction angle (φ), and the logarithm of the shearing rate are linear; (5) the range of c of MBT waste is 22.32–39.51 kPa, and φ is 64.24–68.52°. Meanwhile, the test data are compared with the test data in the literature. The ranges of c and φ of municipal solid waste determined via the shear test are found to be wider than those of MBT waste. The results of this study can provide a reference for the stability calculation of MBT landfills.
Afficher plus [+] Moins [-]Feasibilty of valorizing quarry wastes in the synthesis of geopolymer binders: engineering performances and microstructure
2022
Nemaleu, Juvenal Giogetti Deutou | Belela, Elodie Awam | Nana, Achille | Kaze, Rodrigue Cyriaque | Venyite, Paul | Yanou, Rachel Nkwaju | Djobo, Jean Noel Yankwa | Kamseu, Elie
The exploitation of volcanic rock quarries generates enormous waste, which causes the problem of disposal, leading to rising dust levels in quarries and depositions on nearby farms by runoffs. To address this issue, the development of sustainable solution for their valorization in construction industries is required. The present investigation aims to valorize granite (GW) and basalt (BW) quarry waste powders as partial replacement (up to 20 wt.%) of iron-rich aluminosilicates in the synthesis of geopolymer binders. Both synthesized series of samples were sealed and cured at 7, 14, and 28 days at room temperature before subjecting to various analytical techniques, including the mechanical properties, XRD, FT-IR, TG/DTG, and SEM–EDS. The results showed that both GW and BW powders are efficient to produce sufficient amounts of geopolymer binder, with ensure good cohesion and connectivity between different components within the final matrices. The values of compressive strength were 7.5–35.9 MPa and 6.2–39.7 MPa for laterite/granite and laterite/basalt geopolymer composites, denoted LGA and LBA, respectively. Moreover, the coexistence of the amorphous Na-aluminosilicate, Ca-aluminosilicate, and Na-polyferrosialate species is responsible for the mechanical properties development of the end-products. Based on the findings, the selected quarry wastes appeared to be sustainable and cost-effective materials for the synthesis of low-energy consumption binder, suitable for the production of construction materials.
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