scholarly journals ASSESSMENT OF ECOLOGICAL STATE OF THE VELIKAYA RIVER DELTA BASED ON HYDROCHEMICAL INDICATORS AND STRUCTURE OF PHYTOPLANKTON

2017 ◽  
Vol 1 ◽  
pp. 82
Author(s):  
Tatiana Drozdenko ◽  
Sergei Mikhalap ◽  
Larisa Nikolskaya ◽  
Anna Chernova
Keyword(s):  
Water Quality ◽  
High Speed ◽  
Shannon Index ◽  
Freshwater Ecosystems ◽  
River Delta ◽  
Ecosystem Dynamics ◽  
Polluted Water ◽  
Ecological State ◽  
Sample Collection ◽  
Wide Range

The basis of the existence of freshwater ecosystems is phytoplankton, which produces most of the primary biological production, participates in repair processes and provides a wide range of ecosystem services. The short life cycle and high speed metabolism of microalgae make them ideal objects for ecological monitoring. The aim of the present study is to research the ecological state of the Velikaya river delta based on the species composition of phytoplankton community and some hydrochemical parameters. The sample collection for phytoplankton study and physicochemical measurements was carried out in summer 2016 at five stations representing different ecological locations of the Velikaya river delta. One hundred sixty five species taxa of microalgae belonging to 8 phylums were identified during the research: Bacillariophyta (37%), Chlorophyta (33.9%), Cyanophyta/Cyanobacteria (9.7%), Chrysophyta (6.1%), Euglenophyta (6.1%), Cryptophyta (3%), Dinophyta (3%), Xanthophyta (1.2%). The values of Shannon index indicate the average complexity of the microalgae communities structure. Values of Margalef index characterize the Velikaya river delta as an area of high species richness. Compared to the previous studies, a significant increase in the level of information diversity is observed, indicating an increase in the number of possible flows of substance and energy in the ecosystem. Dynamics of biogen substances in the water shows a slight increase of their concentrations. Ecological and geographical analysis proves that absolute dominance of cosmopolitan freshwater forms is typical for the algoflora of the Velikaya river delta. In relation to the pH-reaction inhabitants of neutral and slightly alkaline water dominate. Pantle–Buck saprobity index is applied for water quality assessment, which shows beta-mesosaprobic water quality in the ecosystem. Thus, the water of the Velikaya river delta could be referred to the category of moderately polluted water (class II of water quality). This is confirmed by the data of hydrochemical analysis.

scholarly journals From existing in situ, high-resolution measurement technologies to lab-on-a-chip – the future of water quality monitoring?

2012 ◽  
Vol 9 (5) ◽  
pp. 6457-6506 ◽  
Author(s):  
A. J. Wade ◽  
E. J. Palmer-Felgate ◽  
S. J. Halliday ◽  
R. A. Skeffington ◽  
M. Loewenthal ◽  
...  
Keyword(s):  
Water Quality ◽  
Lab On A Chip ◽  
Urban System ◽  
Water Quality Monitoring ◽  
Low Flow ◽  
Septic Tank ◽  
Storm Events ◽  
Sample Collection ◽  
Daily Monitoring ◽  
Wide Range

Abstract. This paper introduces new insights into the hydrochemical functioning of lowland river-systems using field-based spectrophotometric and electrode technologies. The streamwater concentrations of nitrogen species and phosphorus fractions were measured at hourly intervals on a continuous basis at two contrasting sites on tributaries of the River Thames, one draining a rural catchment, the River Enborne, and one draining a more urban system, The Cut. The measurements complement those from an existing network of multi-parameter water quality sondes maintained across the Thames catchment and weekly monitoring based on grab samples. The results of the sub-daily monitoring show that streamwater phosphorus concentrations display highly complex, seemingly chaotic, dynamics under storm conditions dependent on the antecedent catchment wetness, and that diurnal phosphorus and nitrogen cycles occur under low flow conditions. The diurnal patterns highlight the dominance of sewage inputs in controlling the streamwater phosphorus and nitrogen concentrations at low flows, even at a distance of 7 km from the nearest sewage works in the rural, River Enborne, and that the time of sample collection is important when judging water quality against ecological thresholds or standards. An exhaustion of the supply of phosphorus from diffuse and septic tank sources during storm events was evident and load estimation was not improved by sub-daily monitoring beyond that achieved by daily sampling because of the eventual reduction in the phosphorus mass entering the stream during events. The dominance of respiration over photosynthesis in The Cut indicated a prevalence of heterotrophic algae, and the seasonal patterns in respiration and photosynthesis corresponded with those of temperature and light in this nutrient over-enriched stream. These results highlight the utility of sub-daily water quality measurements but the deployment of modified wet-chemistry technologies into the field was limited by mains electricity availability. A new approach is therefore needed to allow measurement of a wide range of analytes at a broader range of locations for the development of water quality web-sensor networks. The development and field deployment of a miniaturised "lab-on-a-chip" ion chromatograph is proposed and justified.

A simple and precise method for measuring ammonium in marine and freshwater ecosystems

1999 ◽  
Vol 56 (10) ◽  
pp. 1801-1808 ◽  
Author(s):  
Robert M Holmes ◽  
Alain Aminot ◽  
Roger Kérouel ◽  
Bethanie A Hooker ◽  
Bruce J Peterson
Keyword(s):  
Matrix Effects ◽  
Freshwater Ecosystems ◽  
Sodium Borate ◽  
Sample Collection ◽  
Fluorometric Method ◽  
Simple Method ◽  
Temperature Matrix ◽  
Wide Range ◽  
Substantial Error ◽  
Reaction Proceeds

The accurate measurement of ammonium concentrations is fundamental to understanding nitrogen biogeochemistry in aquatic ecosystems. Unfortunately, the commonly used indophenol blue method often yields inconsistent results, particularly when ammonium concentrations are low. Here, we present a fluorometric method that gives precise measurements of ammonium over a wide range of concentrations and salinities emphasizing submicromolar levels. The procedure not only solves analytical problems but also substantially simplifies sample collection and preservation. It uses a single working reagent (consisting of orthophthaldialdehyde, sodium sulfite, and sodium borate) that is stable for months when stored in the dark. The working reagent and sample can be mixed immediately after sample collection and the reaction proceeds to completion within 3 h at room temperature. Matrix effects and background fluorescence can be corrected without introducing substantial error. This simple method produces highly reproducible results even at very low ammonium concentrations.

scholarly journals THE MODERN STATUS OF THE VELIKAYA RIVER DELTA ON THE STATE OF PRIMARY PRODUCERS

2019 ◽  
Vol 1 ◽  
pp. 48
Author(s):  
Tatiana Drozdenko ◽  
Sergei Mikhalap ◽  
Kristina Mikhaylova ◽  
Anna Chernova
Keyword(s):  
Water Quality ◽  
Natural Waters ◽  
Ecological Status ◽  
Water Quality Assessment ◽  
Water Area ◽  
Freshwater Ecosystems ◽  
The State ◽  
River Delta ◽  
Primary Producers ◽  
Weakly Alkaline

Primary producers are an integral part of freshwater ecosystems. Phytoplankton forms the basis of the trophic pyramid, participates in the formation of water quality and acts as a sensitive indicator of the state of the reservoir. The ability of macrophytes to accumulate mineral and organic substances makes them active participants in the self-purification of natural waters. Higher aquatic plants are characterized by conservatism to short-term changes in the environment, but changes in vegetation over the years may indicate anthropogenic transformation of ecosystems. The contribution to maintaining the stability of the functioning and biodiversity of the ecosystem makes phytoplankton and macrophytes compulsory research objects aimed at studying the state of water bodies. The aim of the work was the study of primary producers as bioindicators of the ecological status of the Velikaya river delta in the summer of 2018. As a result, 127 phytoplankton taxa from 8 phylums were found: Chlorophyta, Bacillariophyta, Cyanobacteria, Euglenophyta, Chrysophyta, Dinophyta, Cryptophyta, Charophyta. The species richness was dominated by the Chlorophyta (42.5%), Bacillariophyta (25.2%), Cyanobacteria (11.1%). According to the ecological and geographical analysis of the delta algaflora, cosmopolitan, freshwater, planktonic forms of microalgae dominate, preferring neutral and weakly alkaline waters. Water quality assessment revealed the beta-mesosaprobic nature of the waters, which indicates moderate pollution of the water area. In the composition of macrophytes, 43 species from 3 phylums were identified: Magnoliophyta, Equisetophyta, Chlorophyta. By species composition, angiosperms dominated (95.3%), of which 46.3% were dicotyledons and 53.7% - monocotyledons. Hygrophytes (34.9%) and hydrophytes (32.6%) prevailed in terms of ecological structure. The leading role in the overgrowing of the delta belonged to high-grass helophytes and rooting hydrophytes with leaves floating on the water. A total of 37 saprobiont flora were found. The total index of saprobity was 277 points.

scholarly journals MONITORING AND MANAGEMENT OF THE RIVER’S ECOLOGICAL STATE METHODOLOGY USING INTEGRAL BIOMARKERS AND QUALITY MANAGEMENT METHODS

2020 ◽  
Vol 12 (4) ◽  
pp. 483-492
Author(s):  
Tatiana GORBUNOVA ◽  
◽  
Natalia MATOVA ◽  
Keyword(s):  
Water Quality ◽  
Quality Management ◽  
Water Environment ◽  
Stress Factors ◽  
Anthropogenic Pressure ◽  
Ecological State ◽  
Biological Communities ◽  
Wide Range ◽  
Six Sigma Approach

The water quality of most rivers near the settlements is below the optimal level, taking in account natural ecosystems condition and numerous needs of various users. Considering the environmental, economic and social importance of this factor, measures are required to improve natural reservoirs water quality management conducted by local civil autonomy and various levels of government. The goal of this work is to offer methodical recommendations on the system design of collecting, analyzing and forming the river’s water and ecosystems conditions database for the information support of complex management decision-making directed to accomplishment and preservation of the water bodies specified functional characteristics. Presently none of the existing methods of water environment assessment can take into account all possible biological communities’ responses to the various stress factors and their combinations impacts. For every type of impact the corresponding to it approaches in sampling and analysis methods are used; values of such methods are often difficult to collate and, especially, provide statistical evaluation of the water streams processes. The presented methods are based on the multimetric index application, which include parameters, reflecting biological communities biodiversity and stability in mountain type rivers, tolerance degree of the constituted them water organisms to external impacts and water environment toxicity for its inhabitants. Modern quality management, including quality of the processes, has a wide range of proven tools. The offered quality management process improvement method of the natural watersheds experiencing an anthropogenic pressure, is aiming to reach stability and guaranteed quality of the natural waters, based on the DMAIC quality management methodology and statistic quantitative methods united under the Six-Sigma approach. This article is the first in publications series devoted to the description of the methodology of the rivers ecological state monitoring and management using integrated biomarkers and quality management methods. Formed during the study organizational and methodical approaches can be applied to digital transformation of effective administrative decisions making process in sphere of water objects protection and development of the river’s catchment territory ecological planning within the project of the RF Construction Ministry “The Smart City”.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

The Impact of High-Speed Rail on the Spatial Structure of Chinese Urban Agglomerations

2020 ◽  
Vol 46 (3) ◽  
pp. 379-397
Author(s):  
Chunyang Wang
Keyword(s):  
High Speed ◽  
River Delta ◽  
City Size ◽  
High Speed Rail ◽  
Local Conditions ◽  
Urban Agglomerations ◽  
Large Cities ◽  
Spatial Systems ◽  
Economic Concentration ◽  
The Impact

This paper measures the spatial evolution of urban agglomerations to understand be er the impact of high-speed rail (HSR) construction, based on panel data from fi ve major urban agglomerations in China for the period 2004–2015. It is found that there are signi ficant regional diff erences of HSR impacts. The construction of HSR has promoted population and economic diff usion in two advanced urban agglomerations, namely the Yang e River Delta and Pearl River Delta, while promoting population and economic concentration in two relatively less advanced urban agglomerations, e.g. the middle reaches of the Yang e River and Chengdu–Chongqing. In terms of city size, HSR promotes the economic proliferation of large cities and the economic concentration of small and medium-sized cities along its routes. HSR networking has provided a new impetus for restructuring urban spatial systems. Every region should optimize the industrial division with strategic functions of urban agglomeration according to local conditions and accelerate the construction of inter-city intra-regional transport network to maximize the eff ects of high-speed rail across a large regional territory.

Survey of the Ecological State of Eight Man-Made Lakes Within the City Limits of Freiburg, Germany

1992 ◽  
Vol 27 (2) ◽  
pp. 301-310
Author(s):  
Agnes G. Pulvermüller ◽  
Heidulf E. Müller
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Biochemical Oxygen Demand ◽  
Secchi Depth ◽  
Oxygen Demand ◽  
Ecological Condition ◽  
Ecological State ◽  
Biological Parameters ◽  
The City ◽  
Oxygen Profiles

Abstract The survey of the ecological condition of eight lakes within the city limits of Freiburg included hydrochemical measurements and analyses (oxygen profiles, Secchi depth, pH, biochemical oxygen demand) together with biological parameters (chlorophyll a, phytoplanktonbiomass, Escherichia coli counts), as well as parasitic examinations. Only some of the investigated parameters are presented here. Seven of the eight lakes were found to be eutrophic. The process of eutrophication appears to be still in progress. One lake can be considered to be hypertrophic. Schistosome dermatitis was observed. The water quality in general was considered to be acceptable; suggestions to maintain or improve the water quality are made.

Objectives of a Water Quality Monitoring Programme for the International River Basins in a Developing Country in Southern Africa – Mozambique

1984 ◽  
Vol 16 (5-7) ◽  
pp. 33-39
Author(s):  
S J Hugman
Keyword(s):  
Water Quality ◽  
Water Resources ◽  
Industrial Development ◽  
Water Quality Monitoring ◽  
Quality Data ◽  
Sample Collection ◽  
Water Quality Data ◽  
Maximum Benefit ◽  
Management And Development ◽  
International Obligations

Mozambique lies on the south-east coast of Africa. Its Independence, in 1975, was particularly difficult and severely disrupted the economy. All its major rivers rise in neighbouring countries and several, in particular those from South Africa and Swaziland, are already heavily used before crossing the border. Since 1977 the National Water Directorate has been responsible for management and development of water resources. The Directorate includes a hydrology department which maintains field-teams throughout the country. Virtually no water quality data are available from before 1972, when irregular sample collection began. Since Independence, sampling has continued but the Directorate has redefined the objectives of the programme to obtain maximum benefit from very limited resources. These objectives were chosen for economic, hydrological and political reasons. The long-term objectives are to provide the data required for agricultural and industrial development projects, to manage and maintain the quality of Mozambique's water resources, and to meet international obligations. In practice, the capacity of the hydrological service is insufficient to meet these objectives. The targets for the existing programme were therefore chosen to satisfy the most important objectives and to be feasible with present resources. The routine programme is being completely operated by technicians who have no more than nine years schooling.

Assessment of Commercial Off-the-Shelf Tissue Adhesives for Sealing Military-Relevant Corneal Perforation Injuries

2021 ◽  
Author(s):  
Eric J Snider ◽  
Lauren E Cornell ◽  
Brandon M Gross ◽  
David O Zamora ◽  
Emily N Boice
Keyword(s):  
Intraocular Pressure ◽  
High Speed ◽  
Anterior Segment ◽  
Ocular Tissue ◽  
Corneal Tissue ◽  
Corneal Perforation ◽  
Tissue Adhesives ◽  
Open Globe ◽  
Wide Range ◽  
Commercial Off The Shelf

ABSTRACT Introduction Open-globe ocular injuries have increased in frequency in recent combat operations due to increased use of explosive weaponry. Unfortunately, open-globe injuries have one of the worst visual outcomes for the injured warfighter, often resulting in permanent loss of vision. To improve visual recovery, injuries need to be stabilized quickly following trauma, in order to restore intraocular pressure and create a watertight seal. Here, we assess four off-the-shelf (OTS), commercially available tissue adhesives for their ability to seal military-relevant corneal perforation injuries (CPIs). Materials and Methods Adhesives were assessed using an anterior segment inflation platform and a previously developed high-speed benchtop corneal puncture model, to create injuries in porcine eyes. After injury, adhesives were applied and injury stabilization was assessed by measuring outflow rate, ocular compliance, and burst pressure, followed by histological analysis. Results Tegaderm dressings and Dermabond skin adhesive most successfully sealed injuries in preliminary testing. Across a range of injury sizes and shapes, Tegaderm performed well in smaller injury sizes, less than 2 mm in diameter, but inadequately sealed large or complex injuries. Dermabond created a watertight seal capable of maintaining ocular tissue at physiological intraocular pressure for almost all injury shapes and sizes. However, application of the adhesive was inconsistent. Histologically, after removal of the Dermabond skin adhesive, the corneal epithelium was removed and oftentimes the epithelium surface penetrated into the wound and was adhered to inner stromal tissue. Conclusions Dermabond can stabilize a wide range of CPIs; however, application is variable, which may adversely impact the corneal tissue. Without addressing these limitations, no OTS adhesive tested herein can be directly translated to CPIs. This highlights the need for development of a biomaterial product to stabilize these injuries without causing ocular damage upon removal, thus improving the poor vision prognosis for the injured warfighter.

scholarly journals Advances and Applications of Water Phytoremediation: A Potential Biotechnological Approach for the Treatment of Heavy Metals from Contaminated Water

2021 ◽  
Vol 18 (10) ◽  
pp. 5215
Author(s):  
Cristián Raziel Delgado-González ◽  
Alfredo Madariaga-Navarrete ◽  
José Miguel Fernández-Cortés ◽  
Margarita Islas-Pelcastre ◽  
Goldie Oza ◽  
...  
Keyword(s):  
Water Quality ◽  
Plant Species ◽  
Treatment Strategies ◽  
Pollution Sources ◽  
Water Contaminants ◽  
Biotechnological Approach ◽  
Wide Range ◽  
Great Relevance ◽  
Multidisciplinary Perspective ◽  
Viable Method

Potable and good-quality drinking water availability is a serious global concern, since several pollution sources significantly contribute to low water quality. Amongst these pollution sources, several are releasing an array of hazardous agents into various environmental and water matrices. Unfortunately, there are not very many ecologically friendly systems available to treat the contaminated environment exclusively. Consequently, heavy metal water contamination leads to many diseases in humans, such as cardiopulmonary diseases and cytotoxicity, among others. To solve this problem, there are a plethora of emerging technologies that play an important role in defining treatment strategies. Phytoremediation, the usage of plants to remove contaminants, is a technology that has been widely used to remediate pollution in soils, with particular reference to toxic elements. Thus, hydroponic systems coupled with bioremediation for the removal of water contaminants have shown great relevance. In this review, we addressed several studies that support the development of phytoremediation systems in water. We cover the importance of applied science and environmental engineering to generate sustainable strategies to improve water quality. In this context, the phytoremediation capabilities of different plant species and possible obstacles that phytoremediation systems may encounter are discussed with suitable examples by comparing different mechanistic processes. According to the presented data, there are a wide range of plant species with water phytoremediation potential that need to be studied from a multidisciplinary perspective to make water phytoremediation a viable method.

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