scholarly journals Assessment of water quality and state of waterbasins of different types from characteristics of benthic animal communities

2016 ◽  
Vol 320 (3) ◽  
pp. 262-279
Author(s):  
E.V. Balushkina

Studies on waterbasins of different type have shown the impact of eutrophication and pollution by toxic and organic matter on the structural and functional characteristics of zoobenthos. A major factor determining quantitative development of non-predatory zoobenthos in lakes is, undoubtedly, the level of development of primary producers. Relationship of zoobenthos biomass and primary production is particularly pronounced in shallow lakes. Analysis of relationship of zoobenthos with abiotic and biotic factors in shallow hyperhaline lakes of Crimea has shown that the most significant parameters determining the values of biomass of macrozoobenthos were salinity and primary production, second in significance were oxygen concentration and depth. The changes in structure and quantitative characteristics of benthic communities of the Neva River estuary occur under impact of a complex combination of organic and toxic pollution. For the assessment of water quality and state of ecosystem in the Neva River estuary we used IP' integrated index specially devised by us for water-bodies and watercourses of north-western Russia. It is based on structural parameters of zoobenthic communities and makes it possible to take into consideration pollution with toxic and organic substances. On average the water quality of the Neva Bay judging from IP' values was relatively stable during 1982–2014. It was assessed as “polluted” with exception for abnormality in 2006 (“polluted–dirty”) caused by large-scale dredging work. As a result of stronger pollution, species diversity of benthic animals in the Resort District of the eastern part of the Gulf of Finland is lower than in the Neva Bay.

1984 ◽  
Vol 11 (4) ◽  
pp. 331-344 ◽  
Author(s):  
Frances B. Michaelis

Considerable public and political debate over the environmental consequences of large-scale operations associated with Tasmania's export forest industries prompted the present review and continuing field-studies. There are no known publications on the effect of forestry on inland waters of Tasmania, but relevant research in the Northern Hemisphere, the Australian mainland, and New Zealand, is summarized.Forest operations considered are roading, logging, and burning. In general, roading increases water-yield, reduces water quality, and modifies the physical structure of streams—particularly at bridge-sites. The impact of logging depends on the harvesting method used (generally, tractor and skidder-logging in Tasmania), the proportion of trees felled, the proportion of the catchment logged, and the precautions taken. However, stream-flows, sediment loads, nutrient levels, dissolved inorganic materials, and wood debris, all increase with logging. If riparian vegetation is cut, water temperature usually increases in summer and decreases slightly in winter, but temperature tolerances of most aquatic animals in Tasmania remain unknown. The effects of burning Australian forests are poorly understood, but there are changes in water-yield and a decrease in water quality.


2017 ◽  
Vol 20 (2) ◽  
pp. 424-439 ◽  
Author(s):  
Hooman Armand ◽  
Ivan Stoianov ◽  
Nigel Graham

Abstract The sectorisation of water supply networks (WSNs) includes the permanent closure of valves in order to achieve a cost-effective leakage management and simplify pressure control. The impact of networks sectorisation, also known as district metered areas (DMAs), on water quality and discolouration has not been extensively studied and it remains unknown. In addition, hydraulic variables used in the literature for assessing the likelihood of potential discolouration are limited and inconclusive. This paper investigates a methodology to evaluate the impact of networks sectorisation (DMAs) on water quality and the likelihood of discolouration incidents. The methodology utilises a set of surrogate hydraulic variables and an analysis of the hydraulic condition in pipes with historic discolouration complaints. The proposed methodology has been applied to a large-scale WSN, with and without sectors, in order to assess the potential impact of DMAs on water quality. The results demonstrate that the sectorisation of WSN (DMAs) could compromise the overall water quality and increase the likelihood of discolouration incidents. The results of this study and the proposed surrogate hydraulic variables facilitate the formulation of optimisation problems for the re-design and control of WSNs with sectorised topologies.


2017 ◽  
Author(s):  
Alexandre V Fassio ◽  
Pedro M Martins ◽  
Samuel da S Guimarães ◽  
Sócrates S A Junior ◽  
Vagner S Ribeiro ◽  
...  

AbstractBackgroundA huge amount of data about genomes and sequence variation is available and continues to grow on a large scale, which makes experimentally characterizing these mutations infeasible regarding disease association and effects on protein structure and function. Therefore, reliable computational approaches are needed to support the understanding of mutations and their impacts. Here, we present VERMONT 2.0, a visual interactive platform that combines sequence and structural parameters with interactive visualizations to make the impact of protein point mutations more understandable.ResultsWe aimed to contribute a novel visual analytics oriented method to analyze and gain insight on the impact of protein point mutations. To assess the ability of VERMONT to do this, we visually examined a set of mutations that were experimentally characterized to determine if VERMONT could identify damaging mutations and why they can be considered so.ConclusionsVERMONT allowed us to understand mutations by interpreting position-specific structural and physicochemical properties. Additionally, we note some specific positions we believe have an impact on protein function/structure in the case of mutation.


Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4042
Author(s):  
Gürkan Kumbaroğlu ◽  
Cansu Canaz ◽  
Jonathan Deason ◽  
Ekundayo Shittu

This paper focuses on the interdependent relationship of power generation, transportation and CO2 emissions to evaluate the impact of electric vehicle deployment on power generation and CO2 emissions. The value of this evaluation is in the employment of a large-scale, bottom-up, national energy modeling system that encompasses the complex relationships of producing, transforming, transmitting and supplying energy to meet the useful demand characteristics with great technological detail. One of such models employed in this analysis is the BUEMS model. The BUEMS model provides evidence of win-win policy options that lead to profitable decarbonization using Turkey’s data in BUEMS. Specifically, the result shows that a ban on diesel fueled vehicles reduces lifetime emissions as well as lifetime costs. Furthermore, model results highlight the cost-effective emission reduction potential of e-buses in urban transportation. More insights from the results indicate that the marginal cost of emission reduction through e-bus transportation is much lower than that through other policy measures such as carbon taxation in transport. This paper highlights the crucial role the electricity sector plays in the sustainability of e-mobility and the value of related policy prescriptions.


2020 ◽  
Author(s):  
Devanshi Pathak ◽  
Michael Hutchins ◽  
François Edwards

<p>River phytoplankton provide food for primary consumers, and are a major source of oxygen in many rivers. However, high phytoplankton concentrations can hamper river water quality and ecosystem functioning, making it crucial to predict and prevent harmful phytoplankton growth in rivers. In this study, we modify an existing mechanistic water quality model to simulate sub-daily changes in water quality, and present its application in the River Thames catchment. So far, the modelling studies in the River Thames have focused on daily to weekly time-steps, and have shown limited predictive ability in modelling phytoplankton concentrations. With the availability of high-frequency water quality data, modelling tools can be improved to better understand process interactions for phytoplankton growth in dynamic rivers. The modified model in this study uses high-frequency water quality data along a 62 km stretch in the lower Thames to simulate river flows, water temperature, nutrients, and phytoplankton concentrations at sub-daily time-steps for 2013-14. Model performance is judged by percentage error in mean and Nash-Sutcliffe Efficiency (NSE) statistics. The model satisfactorily simulates the observed diurnal variability and transport of phytoplankton concentrations within the river stretch, with NSE values greater than 0.7 at all calibration sites. Phytoplankton blooms develop within an optimum range of flows (16-81 m<sup>3</sup>/s) and temperature (11-18° C), and are largely influenced by phytoplankton growth and death rate parameters. We find that phytoplankton growth in the lower Thames is mainly limited by physical controls such as residence time, light, and water temperature, and show some nutrient limitation arising from phosphorus depletion in summer. The model is tested under different future scenarios to evaluate the impact of changes in climate and management conditions on primary production and its controls. Our findings provide support for the argument that the sub-daily modelling of phytoplankton is a step forward in better prediction and management of phytoplankton dynamics in river systems.</p>


Ocean Science ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 195-208
Author(s):  
Thodoris Karpouzoglou ◽  
Brigitte Vlaswinkel ◽  
Johan van der Molen

Abstract. An improved understanding of the effects of floating solar platforms on the ecosystem is necessary to define acceptable and responsible real-world field implementations of this new marine technology. This study examines a number of potential effects of offshore floating solar photovoltaic (PV) platforms on the hydrodynamics and net primary production in a coastal sea for the first time. Three contrasting locations within the North Sea (a shallow and deeper location with well-mixed conditions and a seasonally stratifying location) have been analysed using a water column physical–biogeochemical model: the General Ocean Turbulence Model coupled with the European Regional Seas Ecosystem Model – Biogeochemical Flux Model (GOTM-ERSEM-BFM). The results show strong dependence on the characteristics of the location (e.g. mixing and stratification) and on the density of coverage with floating platforms. The overall response of the system was separated into contributions by platform-induced light deficit, shielding by the platforms of the sea surface from wind and friction induced by the platforms on the currents. For all three locations, light deficit was the dominant effect on the net primary production. For the two well-mixed locations, the other effects of the platforms resulted in partial compensation for the impact of light deficit, while for the stratified location, they enhanced the effects of light deficit. For up to 20 % coverage of the model surface with platforms, the spread in the results between locations was relatively small, and the changes in net primary production were less than 10 %. For higher percentages of coverage, primary production decreased substantially, with an increased spread in response between the sites. The water column model assumes horizontal homogeneity in all forcings and simulated variables, also for coverage with floating platforms, and hence the results are applicable to very-large-scale implementations of offshore floating platforms that are evenly distributed over areas of at least several hundreds of square kilometres, such that phytoplankton remain underneath a farm throughout several tidal cycles. To confirm these results, and to investigate more realistic cases of floating platforms distributed unevenly over much smaller areas with horizontally varying hydrodynamic conditions, in which phytoplankton can be expected to spend only part of the time underneath a farm and effects are likely to be smaller, spatial detail and additional processes need to be included. To do so, further work is required to advance the water column model towards a three-dimensional modelling approach.


2015 ◽  
Vol 12 (13) ◽  
pp. 4085-4098 ◽  
Author(s):  
R. Aguilera ◽  
R. Marcé ◽  
S. Sabater

Abstract. Attributing changes in river water quality to specific factors is challenging because multiple factors act at different temporal and spatial scales, and it often requires examining long-term series of continuous data. Data consistency is sometimes hindered by the lack of observations of relevant water quality variables and the low and uneven sampling frequency that characterizes many water quality monitoring schemes. Nitrate and dissolved phosphate concentration time series (1980–2011) from 50 sampling stations across a large Mediterranean river basin were analyzed to disentangle the role of hydrology, land-use practices, and global climatic phenomena on the observed nutrient patterns, with the final aim of understanding how the different aspects of global change affected nutrient dynamics in the basin. Dynamic factor analysis (DFA) provided the methodological framework to extract underlying common patterns in nutrient time series with missing observations. Using complementary methods such as frequency and trend analyses, we sought to further characterize the common patterns and identify the drivers behind their variability across time and space. Seasonal and other cyclic patterns were identified as well as trends of increase or decrease of nutrient concentration in particular areas of the basin. Overall, the impact of global change, which includes both climate change and anthropogenic impacts, on the dynamics of nitrate concentration across the study basin was found to be a multifaceted process including regional and global factors, such as climatic oscillations and agricultural irrigation practices, whereas impacts on phosphate concentration seemed to depend more on local impacts, such as urban and industrial activities, and less on large-scale factors.


2019 ◽  
Vol 13 (2) ◽  
pp. 105-111 ◽  
Author(s):  
O. O. Portyannikova ◽  
S. M. Tsvinger ◽  
A. V. Govorin ◽  
E. N. Romanova

The review contains data from large-scale foreign and Russian studies of the epidemiology of osteoarthritis (OA). It considers the role of modifiable and non-modifiable risk factors for OA, such as age, sex, hormonal status, obesity, etc. There are data on genetic susceptibility to OA and on congenital anomalies that contribute to joint structural changes. Data on the impact of racial and ethnic factors on the development and progression of OA are analyzed. The role of metabolic disorders in the pathogenesis of this disease is highlighted. Data on the relationship of OA to patients' professional activities are summarized.


2020 ◽  
Vol 113 (5) ◽  
pp. 359-372
Author(s):  
Rosa N Grueso-Gilaberth ◽  
Keiner S Jaramillo-Timarán ◽  
Erika M Ospina-Pérez ◽  
Vinicius S Richardi ◽  
Paula A Ossa-López ◽  
...  

Abstract The Neotropical region has a wide aquatic biodiversity, which is affected by anthropogenic activities. Mining has caused a negative impact on these ecosystems, directly affecting benthic communities. Aquatic macroinvertebrates are effective bioindicators of water quality, especially Chironomidae larvae, since these show high species richness, abundance, and sensitivity to human activities. The genus Polypedilum is among the most representative of the family Chironomidae. Research on these species is focused on their abundance and dominance in water bodies. In addition, several studies have addressed alterations in the external morphology of some Chironomidae due to mining pollution (heavy metals). However, little is known about the effects of mining on the internal morphology of these species. This study provides the first histological description of different systems and organs of Polypedilum sp. larvae. Furthermore, we report histopathological alterations in larvae collected from two tributaries affected by mining, namely Toldafría and La Elvira streams located in the municipalities of Villamaría and Manizales (Caldas – Colombia). Our findings show target organs of mining pollution in a species of Polypedilum, which represent potential early-warning histopathological biomarkers with relevant implications for water quality monitoring.


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