Microplastic Pollution in Freshwater Systems: A Potential Environmental Threat

2021 ◽  
pp. 341-356
Author(s):  
Vicky Singh ◽  
Sukalyan Chakraborty
Keyword(s):  
Freshwater Systems ◽  
Environmental Threat

An analysis of major environmental threats to human security in Nepal

2020 ◽  
Vol 4 (1) ◽  
pp. 129-139
Author(s):  
Naresh Bhakta Adhikari
Keyword(s):  
Climate Change ◽  
Agricultural Production ◽  
Human Security ◽  
Well Being ◽  
Environmental Security ◽  
Government Action ◽  
Environmental Threats ◽  
Environmental Threat ◽  
Analytical Research ◽  
The Government

The paper mainly analyses the environmental threats focusing on climate change to human security in Nepal. Major aspects of human security are interlinked and interconnected in our context. Among them, human security offers much to the vibrant field of environmental security in Nepal. Environmental threats are linked to the overall impact on human survival, well-being, and productivity. A great deal of human security is tied to peoples’ access to natural resources and vulnerabilities to environmental change. The major environmental threats in our context is the climate change which have widespread implications for Nepal, causing impacts to water availability, agricultural production, forestry, among many other detrimental effects. The critical threat of environmental security needs to be taken into serious consideration to save our succeeding generation. This article primarily interpreted the government action towards emerging environmental threat based on realist approach. For the study of theme of this article, descriptive and analytical research has been used to draw present major environmental threats in Nepal. With consideration to factors, this article attempted to identify the major environmentally vulnerable areas that are likely to hamper the overall status of human security in Nepal. This paper also tried to suggest the measures to enhance the environmental security considering prospects and policy focusing on Nepalese diverse aspects.

Fish stranding in freshwater systems: Sources, consequences, and mitigation

2012 ◽  
Vol 103 ◽  
pp. 133-141 ◽  
Author(s):  
Alexander Nagrodski ◽  
Graham D. Raby ◽  
Caleb T. Hasler ◽  
Mark K. Taylor ◽  
Steven J. Cooke
Keyword(s):  
Freshwater Systems

scholarly journals Plastic waste to fuels by hydrocracking at mild conditions

2021 ◽  
Vol 7 (17) ◽  
pp. eabf8283
Author(s):  
Sibao Liu ◽  
Pavel A. Kots ◽  
Brandon C. Vance ◽  
Andrew Danielson ◽  
Dionisios G. Vlachos
Keyword(s):  
Direct Method ◽  
Acid Sites ◽  
Liquid Fuels ◽  
High Yield ◽  
Tandem Catalysis ◽  
Hy Zeolite ◽  
Environmental Threat ◽  
Single Use ◽  
Initial Activation ◽  
A Direct Method

Single-use plastics impose an enormous environmental threat, but their recycling, especially of polyolefins, has been proven challenging. We report a direct method to selectively convert polyolefins to branched, liquid fuels including diesel, jet, and gasoline-range hydrocarbons, with high yield up to 85% over Pt/WO3/ZrO2 and HY zeolite in hydrogen at temperatures as low as 225°C. The process proceeds via tandem catalysis with initial activation of the polymer primarily over Pt, with subsequent cracking over the acid sites of WO3/ZrO2 and HY zeolite, isomerization over WO3/ZrO2 sites, and hydrogenation of olefin intermediates over Pt. The process can be tuned to convert different common plastic wastes, including low- and high-density polyethylene, polypropylene, polystyrene, everyday polyethylene bottles and bags, and composite plastics to desirable fuels and light lubricants.

scholarly journals eDNA in a bottleneck: Obstacles to fish metabarcoding studies in megadiverse freshwater systems

2021 ◽  
Author(s):  
Jake M. Jackman ◽  
Chiara Benvenuto ◽  
Ilaria Coscia ◽  
Cintia Oliveira Carvalho ◽  
Jonathan S. Ready ◽  
...  
Keyword(s):  
Freshwater Systems

scholarly journals Utilization of low molecular weight organic compounds by the filterable fraction of a lotic microbiome

2020 ◽  
Author(s):  
Lydia-Ann J Ghuneim ◽  
Marco A Distaso ◽  
Tatyana N Chernikova ◽  
Rafael Bargiela ◽  
Evgenii A Lunev ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Community Dynamics ◽  
Lag Phase ◽  
Minor Role ◽  
Low Molecular Weight ◽  
Freshwater Systems ◽  
North Wales ◽  
Clusters Of Orthologous Groups ◽  
A Minor ◽  
Substrate Addition

Abstract Filterable microorganisms participate in dissolved organic carbon (DOC) cycling in freshwater systems, however their exact functional role remains unknown. We determined taxonomic identity and community dynamics of prokaryotic microbiomes in the 0.22 µm-filtered fraction and unfiltered freshwater from the Conwy River (North Wales, UK) in microcosms and, using targeted metabolomics and 14C-labelling, examined their role in utilization of amino acids, organic acids, and sugars spiked at environmentally-relevant (nanomolar) concentrations. To identify changes in community structure, we used 16S rRNA amplicon and shotgun sequencing. Unlike the unfiltered water samples where the consumption of DOC was rapid, the filtered fraction showed a 3-days lag phase before the consumption started. Analysis of functional categories of clusters of orthologous groups of proteins (COGs) showed COGs associated with energy production increased in numbers in both fractions with substrate addition. The filtered fraction utilized low-molecular-weight (LMW) DOC at much slower rates than the whole community. Addition of nanomolar concentrations of LMW DOC did not measurably influence the composition of the microbial community nor the rate of consumption across all substrate types in either fraction. We conclude that due to their low activity, filterable microorganisms play a minor role in LMW DOC processing within short residence time of lotic freshwater systems.

scholarly journals Preliminary Screening for Microplastic Concentrations in the Surface Water of the Ob and Tom Rivers in Siberia, Russia

2020 ◽  
Vol 13 (1) ◽  
pp. 80
Author(s):  
Yulia A. Frank ◽  
Egor D. Vorobiev ◽  
Danil S. Vorobiev ◽  
Andrey A. Trifonov ◽  
Dmitry V. Antsiferov ◽  
...  
Keyword(s):  
Surface Water ◽  
Arctic Ocean ◽  
River System ◽  
The Arctic ◽  
Preliminary Screening ◽  
Freshwater Systems ◽  
Ob River ◽  
The Arctic Ocean ◽  
Abundance And Diversity ◽  
Blank Spot

To date, the largest Russian rivers discharging to the Arctic Ocean remain a “blank spot” on the world map of data on the distribution of microplastics in freshwater systems. This study characterizes the abundance and morphology of microplastics in surface water of the Ob River and its large tributary, the Tom River, in western Siberia. The average number of particles for the two rivers ranged from 44.2 to 51.2 items per m3 or from 79.4 to 87.5 μg per m3 in the Tom River and in the Ob River, respectively. Of the recovered microplastics, 93.5% were less than 1 mm in their largest dimension, the largest group (45.5% of total counts) consisted of particles with sizes range 0.30–1.00 mm. Generally, microfragments of irregular shape were the most abundant among the Ob and Tom samples (47.4%) and exceeded microfibers (22.1%), microfilms (20.8%), and microspheres (9.74%) by average counts. Results from this study provide a baseline for understanding the scale of the transport of microplastics by the Ob River system into the Arctic Ocean and add to currently available data on microplastics abundance and diversity in freshwater systems of differing global geographic locations.

Sign in / Sign up

Export Citation Format

Share Document