Total Environment Research Themes最新文献

Over the decades, there has been an increase in the number of Emerging Contaminants (ECs) in different aquatic compartments. These ECs do have a direct effect on marine organisms and indirect impacts on human health. Numerous studies regarding the ECs detection, fate, and health impacts are confined to developed nations. Indian River systems have remained the epitome of pollution due to unregulated treatment and discharge of pollutants from different sources. Therefore, this studies providing an adequate sound knowledge of identifying ECs in Indian rivers become of utmost importance. The current study focuses on the identification of ECs in the Ganges in three major cities, respectively, in three belts of Indo-Gangetic plains. Hydroxymorphinan, picrotoxinin, antibiotic quinolone, and nefopam are common drugs found at different locations in the Ganga basin. ECs and the frequency of each EC have been identified for various locations and estimated with some basic consideration. Interestingly, Ethylhexyl ester is primarily used in pesticide manufacturing and is a common problem for the middle and lower Ganga basins. Besides, personal care products, insecticides, herbicides, pesticides, and flavoring agents are major sources of ECs in the Ganga basin. The trends of concentration of various ECs from upper towards downstream were analyzed and justified with sources. Lastly, this manuscript concluded with various recommendations related to the control of unloading and releasing the effluents in the Ganga and biomonitoring the organic contaminants, along with toxic ECs.

A bioelectrochemical system is a form of bioengineering technology that has been popularly employed in treating wastewater and energy recovery. However, most of the recent studies in the field of bioelectrochemical technology have mainly focused on scalable architectural designs of the system, while research on the selection of a suitable biocatalyst for the improvement of bioelectrochemical cleanup of pollutants has been given insufficient consideration. The three major limitations of improving bioelectrochemical cleanup technology are time consumption, high cost, and non-nature-based catalyst. In this study, a new bioelectrochemical compartment (BC) incorporating a biochar-based catalyst was fabricated to determine the upscaling effect on the cleanup of nitrate (NO₃) and ammonia (NH₃) from an aqueous solution. The two different bioelectrochemical reactors used in this experiment were denoted as System 1 (control), and System 2 (experimental), which were later expressed as S1 and S2, and the wastewater sample used was activated sludge. The highest cleanup efficiency of NO₃ (99%) was achieved in S2 when the BC was operated with a biochar-based catalyst compared to that of the which was 95%. However, the cleanup efficiencies of NH₃ were 96% and 67% in S1 and S2, respectively. This outcome indicated that the highest cleanup efficiency of NH₃ was achieved in S1. In addition, we monitored biogas generation in each BC and recovered a significant quantity of CO_2, N₂O, and CH₄. Sporosarcina, Tissierala from the species of Firmicutes, and Pseudomonas of phylum Proteobacteria were the most abundant bacteria that supported the cleanup of pollutants in this study.

Seaweed cultivation is an emerging sector of food production that can full fill the future food demand of the growing population. Considering the importance, Asia is home to seven of the top ten seaweed-producing nations, and Asian countries contributed 99.1% of all seaweed cultivated for food. Besides, it can reduce the carbon budget of the ocean through seaweed farms and act as a CO₂ sink. In the context of climate change mitigation, the seaweed culture is the energy crop, and during its entire life cycle can serve as a bio-filter and bio-extractor. The climate change effect can be reduced by farming seaweed on a commercial scale and it will protect the coastal area by decreasing the physical damage through damping wave energy. The seaweed can reduce eutrophication by removing excess nutrients from water bodies and releasing oxygen as a byproduct in return. The cultivation of seaweed plays an important role as the source of bioenergy for full fill the future energy requirement and it will act as clean energy through the establishment of algal biorefinery along with the seaweed cultivation site. Thus, the marine energy industrial sector moves further toward large-scale expansion of this sector by adopting energy devices to offer power for seaweed growth for biofuel operation. The current reviews provides the evidence of seaweed farming methodology adopted by different countries, as well as their production and output. To mitigate climate change by direct measures such as carbon sequestration, eutrophication risk reduction, and bioenergy, as well as through indirect measures like supplying food for cattle and reducing the strain on aquaculture. The US, Japan, and Germany lastly suggest the large-scale offshore commercial farming as a feasible climate change mitigation strategy.

Natural fibres have recently emerged as a pool of organic compounds that for different applications. Among several natural products, the fibres of Bombax ceiba contain several naphthalene-based compounds. Hence, Bombax ceiba may exhibit the potential of adsorbing a variety of pollutants. In this study, the adsorption of arsenite (As(III)) and arsenate (As(V)), from the aqueous stream was investigated using density functional theory (DFT) calculations. 1,4-Naphthaquinone, 1-Naphthyl ether, Hemigossypol, and Naphthol were chosen as adsorbent molecules for As(III) and As(V) ions as they form the major portion of the Bombax ceiba fibres. CAM-B3LYP/6-311G level of DFT theory was used to calculate electrostatic potential maps, HOMO-LUMO distributions, chemical potential, and hardness to gain quantitative information on the interactions. The adsorption energies and recovery time were calculated based on the thermodynamic feasibility of the interactions of As(III) and As(V) ions with Bombax ceiba fibres. The results showed that As(III) and As(V) ions adsorbed physically on the Bombax ceiba fibres. The results can be used to further modify naturally occurring Bombax ceiba fibres to develop sustainable solutions.

Assessment of the marine ecosystem function and energy and matter fluxes in marine food web requires the knowledge on light field in the sea upper layer. Detailed information about light field needed for correct assessment of the primary production in the sea. To describe downwelling irradiance in the sea the vertical distribution of the all in water optically active components should be known. The mean profile and two eigenvectors of chlorophyll-a concentration, particle backscattering coefficient, colored dissolved organic matter absorption coefficient and temperature have been derived from bio-Argo float data within 0–70 m layer with 5 m resolution. Long-term (2013–2018) dataset of bio-Argo float data have been used to get ten-days averaged parameter values - 37 data subsets/year. To get link between surface satellite data and statistics (parameter profiles) derived from bio-Argo float the chlorophyll-a concentration, light absorption coefficient of colored detrital matter at 490 nm and particle backscattering coefficient at 555 nm retrieved based on regional algorithms, temperature - standard satellite product have been related with statistics derived from bio-Argo float measurements of chlorophyll-a concentration, particle backscattering, colored dissolved organic matter and temperature in surface layer. The obtained relationships allowed to solve the task - to retrieve 4D fields (x,y,z,t) of parameters in the 0–70 m layer of the Black Sea.

This article describes a simple generic system dynamics model of resource dependency in ecosystems to explore the potential range of behaviours that can arise purely due to system structure. The model produces a small number of behaviours that replicate the observed real-world behaviour of ecosystems but does not produce the less plausible outcomes produced in simpler predator–prey models (e.g. Lotka Volterra) such as exponential growth or exploding oscillations. The more limited range of behaviours is attributed to the inclusion in the model of species dependence on abiotic resource flows. The simulations explore the response of systems in equilibrium to various types of ‘shock’ and the outcomes are used to reflect on the concepts of resilience and sustainability. The results challenge the normative understanding of these terms and their relationship to each other. The results also reinforce the notion that shocks to the abiotic system flows at the foundation of all ecosystems present the greatest threat to ‘resilience’ as they affect all trophic levels.

Heavy metal contamination in sediments poses serious threat to ecosystem and human health through food web. In this study, surface sediment samples from Kavvayi estuary were analyzed to understand the sources and pollution levels of heavy metals. The results revealed that the average contents (μg g⁻¹) of eight selected heavy metals followed the order of Mn (65–795) > Cr (30–442) > Co (30–250) > Ni (15–175) > Zn (20–120) > Cu (5–55) > Pb (5–40). Enrichment factor (EF) and contamination factor (CF) analyses revealed that Pb, Ni and Cr shows moderate pollution levels, whereas Co indicates severe pollution levels. The rests of the heavy metals (Zn, Cu and Mn) were at no to low pollution levels. The correlation matrix combined with multivariate principal component analysis suggests the heavy metals, except for Co, mainly originated from natural weathering and erosion of rocks and soils in the catchment. The results of this study provide a comprehensive assessment of heavy metal contamination in the sediments of the Kavvayi region. The result can aid the development of effective remediation strategies and improve government decision-making and coastal management.

Hazardous substances originating from aromatic compounds pose seriously harmful effects on aquatic animals and the environment, which has received the attention for the treatment. This work used Multi-Walled Carbon Nano-Tubes (MWCNTs) modified with vanadium-pentoxide V₂O₅ nanoparticles and 2 wt% of different nanocomposite mixtures to remove methylene blue from water. The process for adsorption has been carried out using different metal oxides modified MWCNTs and V₂O₅/MWCNTs resulting in the highest adsorption capacity, 50.93 mg/g for methylene blue). The V₂O₅:CeO₂ nanocomposites modified MWCNTs exhibited the highest removal efficiency with 63.77 %, superior to previous studies.

Antibiotics are identified as an emerging contaminant due to their persistence in the environment. Antibiotics, due to their accumulation in freshwater sources and wastewater have become a pollutant of concern. Every year million tons of these emerging contaminants are discharged into the water bodies. Through, the feces and urine of humans and animals, the antibiotics and their metabolites enter the environment. Aquatic ecosystems are exposed to persistent pollutants as they escape the wastewater treatment process. Excessive usage of antibiotics has resulted in the generation of antibiotic-resistant genes and bacteria in the environment. To maintain the vitality of the environment, it becomes imperative to mitigate antibiotics and their toxic metabolites. To avoid the adverse consequences on the non-target organisms, their removal from the environment is vital. Various remediation methods such as conventional methods including ion exchange, and precipitation are used for antibiotics degradation, however, the efficacy of the traditional methods is limited due to the production of toxic sludge and the high cost of maintenance. Biological methods such as bioremediation and phytoremediation are sustainable strategies to eradicate antibiotics, hence used widely. There are many reviews on antibiotic bioremediation using microbes and phytoremediation of antibiotics. But not all antibiotics can be remediated using microorganisms, so there is a need for more sustainable removal methods and recent remediation strategies. In the present review, a web-based search for literature published between 2010 and 2022 is carried out. Previous studies reported that living organisms like bacteria, fungi, algae, and plants could be utilized for the degradation of antibiotics. But not all antibiotics could be degraded using bacteria, as bioremediation may get affected by many factors such as inoculum size, microbial strain, and the culture conditions. Therefore, recent remediation techniques such as the use of microbial fuel cells, biochar, and sawdust are used for the possible removal of antibiotics from the environment. For the sustainable elimination of recalcitrant antibiotics, combined processes seem to be a more efficient and permanent solution for bypassing the toxicity of antibiotics.

The continuous worldwide pandemic of COVID-19 brought about by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a public health emergency of international concern, which was formally announced by the World Health Organization (WHO). The antivirals utilized to restrict the spread of virus and the procedures for the recognition of SARS-COV-2 in wastewater has been reviewed. A main tool Wastewater-based epidemiology (WBE) played a notable role in tracking the spread of corona virus in large community. This review signifies the upgraded clinical impacts and components of Traditional Chinese Medicine (TCM), the function of various antiviral drugs against COVID 19 and the role of human covid to exist in the habitat and the viability countered; with specific spotlight on the advancement of latest strategies to assess the action of latest antiseptic-disinfectants on infections.