Science topic

Water Quality - Science topic

Water quality is about the chemical and biological constituents of water. It comprises: 1) Water chemistry data compilations; 2) Development of reliable sampling and analytical protocols; 3) Research about water-rock, water-soil and water-atmosphere interactions; 4) Identification of water-contamination sources; 5) development of remediation strategies for poor-quality water. Water quality often means the difference in constituent concentrations between field samples and standard concentrations set by governmental authorities to protect human and ecosystem health. It is distinct from water quantity, which is broadly equivalent to physical hydrology.
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Please suggest me latest software to analyse the land use/land cover impact on water quality of river basin.
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If you have actual water quality data: One thing I've done in the past is used QGIS (free GIS software) with the GRASS plugin (also free), and GIS layers for land use (from the government), to determine the land uses in each sub-watershed. And then compared water quality data to the percentage of land uses. This was not very easy, but the results were somewhat informative.
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We performed two water quality tests, 1) pre-filter that showed no Lead and 2) post-filter that showed lead (0.0048ppm). The filter is an under-the-sink reverse osmosis system (https://nuaquasystems.com/products/nu-aqua-platinum-series-7-stage-alkaline-and-uv-ultraviolet-100gpd-ro-system).
Any ideas on how this is possible?
Thank you
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There are three possible reasons that I can think of Jose
Error in the analysis of the water samples.
Contamination from/by the membrane and or its housing materials
From an accumulation of lead on the membrane that 'breaks through'. Although the lead in your feed water is below the level of detection, these very low levels can probably accumulate slowly to measurable levels.
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I would be very appreciative if you introduce a valid guideline for water quality parameters for wildlife habitats.
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I have worked in the discipline of wildlife toxicology for more than 35 years, with a focus on USA water quality. There are no such comprehensive standards from EPA, although they exist for a very few individual pollutants such as mercury, selenium, organochlorines, etc., on a regional basis... The Great Lakes Initiative comes to mind. I also have never encountered any systematic compilation of recommended guidelines or standards from any other USA government agency or non-government entity. I'm hoping you will have better luck in responses from those who know International organizations. Looks like Dan Webster has already put you on a good start there. Good Luck.
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What is clearer is the question of water quality in terms of qualitative characteristics, whether or not they change?
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Hello! I am putting together a dataset of benthic macroinvertebrate monitoring / count data from estuaries and coastlines along the North American Coast (Canada and US). I know of larger datasets like the NCCOS National Benthic Inventory and EMAP, but I was wondering if anyone knew of other regional datasets. It would be preferable if the data were collected using Young-modified Van Veen grab samplers along with information on water quality and sediment quality, but any dataset recommendations will be greatly appreciated!
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Marcus W. Beck Yes, I am still on the hunt for more data! Thank you for sharing the links to the Tampa Bay monitoring data, I did not know about them. I will take a look at them!
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How to measure water quality through Remote Sensing? What methods, data and concepts can be used for this?
-Thank you-
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Google Scholar is your friend ( see graphic )
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Dear researchers,
Since WQI models are not generic and there are more than 35 ones, what is the suitable model (WQI) to assess spring water quality?
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Water is considered as the most important and valuable natural resource on which all life on earth ultimately depends. Water plays an imperative role in the development of different sectors of the economy, including agriculture, cattle production, forestry, industrial electricity generation, fisheries, and other innovative activities. Over the past few decades, the water quality index (WQI) has been considered as an effective tool that provides information on the quality of water for use by concerned citizens and policymakers and has been utilised in surface and groundwater quality evaluation all over the world.
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Hi
Can anyone assist with correcting the error we have in HEC-RAS 6.2 water quality. Please see attached file.
Thanks
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Did you ever sort this problem out? I have a similar problem with a WQ simulation using version 5.0.7
It is not a date format as i have fixed everything as steady flows
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How to get online sensor data for water quality? Is there any website available for that? If anybody knows the details please share.
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Dear Atanu,
you can start with data descriptors published in Data Science.
All articles are open access and have information about the data repository.
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What is the best (low cost and high efficient) method (Physical, Chemical, or Biological) of wastewater treatment to meet irrigation water quality ranges?
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S
Waste water sludge management is a new method adopted in populated areas to cultivated periseable crop for human consumption. Waste water might contain organic substance which are of benefit for the plants growth. Make sure to use sanitizer in the process to avoid contamination.
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Hi everyone...
I am currently working on water quality. and I would like to know how to conduct sensitivity analysis for water quality and enter the data in Excel.
Best Regards,
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One lake suffered great damage in terms of water use and catch due to the deterioration of water quality. As a measure to improve water quality, the development of sewage treatment plants and the spread of cultivation methods with reduced amounts of chemical fertilizers were promoted, and the water quality was significantly improved. However, as a result of the dramatic improvement in water quality (decrease in nutrient concentration and COD concentration), the fish catch recovered once, but tended to gradually decrease. The fishermen's union has raised the issue of reduced catches due to improved water quality and is calling on local governments that have promoted water quality improvement policies to return to their original water quality.
Devise the best possible solution to this problem. Also, explain the scientific basis for that solution in a comprehensive way.
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Phytoremediation is an effective approach
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I am pursuing Ph.D. on anthropogenic impact on fluvial environment. This is my last year my work is almost complete. Can anyone walk me through the process of pursuing PDF in India or preferably abroad? I have one international publication in springer on water quality and two other are in the pipeline on river migration process and anthropogenic impact on rivers.
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I apparently missed your added elements on publishing and subject areas. There are universities, professors, researchers and companies that deal with hydrology, geomorphology, water quality, etc. You might try developing in adjustable format to apply to all these circumstances you identify through time, and send letters of interest in their specific programs. Unless you know already, you might need to conduct internet searches on the topics mentioned. Countries and communities that have had impacts from flooding, sedimentation, etc. might also have engineering firms who would be interested in directing your skills toward their issues. You might contact the American Institute of Hydrology to see if they have any information suitable to your interests. They certify professional hydrologists in the USA.
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I need a water quality-quantity model for improving the water quality of the Amirkabir dam, and I don’t know considering the limitations and advantages of both models: SWAT and MIKE 11 which one would be a better choice?
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With SWAT, only data availability is the issue. If you are having high-quality data (especially DAM related data for the basin) then, you should go with the SWAT. It is very reliable and gives great results.
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Policy discussions and scientific studies today omit the important linkages between water quality and climate change, whereas the impacts of climate change on the quality of freshwater systems are likely to be significant. More scientific understanding is hence needed to address the physical, chemical, biological and socio-economic impacts that current and expected climate change have, and will continue to have, on the quality of the world’s freshwater resources. In this context, what do you think are the impact of climate change on water quality?
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I was unable to perform the sampling and analysis for 40 surface water and 20 groundwater samples, so I hired an in-country consultant firm to do it. The results that they returned were difficult to interpret and had extremely high levels of iron and manganese. I spoke with a former professor and he expressed concern from his long career of working in SE Asia that the subcontractor/lab might not have filtered the samples. How can I know that the results are for the water and not the particulates?
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Dear Liz Kendall . Do the analysis of the same samples at different labs then compare the results. See which results are the same and exclude the results that are far way from the comparable results. Then you can judge which lab is trusted and which is not. Best wishes.
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Hi all,
I am looking for models like Vollenweider Loading Plots and want to calculate and predict eutrophication in some reservoirs. I have some data about their incoming monthly flows, incoming flows quality, their capacity, and so on.
Could you please introduce me to other models?
Thanks a lot.
Alireza Shahmirnoori
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Personally, I strongly recommend this article which will certainly be useful to you.
Regards
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Does the slope factor (SF) and reference dose values (RFD) for different metals remain constant when assessing the risks of heavy metals in water, soil, or sediments?
If it is different according to the environment, please provide us with the values ​​of each environment.
Thanks
Azzeddine.
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The essential step in solving a water quality problem is to obtain a reliable water sample and analysis
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Self realisation and awareness about the importance of water and its quality is main to solve the problem.
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I have predicted the trend in water quality using past 12 years data. My aim is to predict the impact of climate change on groundwater quality for coming decades. In order to achieve so, which data and software is required I am not so sure about it.
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I suggest you try Eureqa Nutonian it is very efficient and reliable. You can use a free trial version.
regards
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I am searching on standard books on secondary WW treatment options such as oxidation ditch and maturation ponds. I would like to know which books do you recommend for students.
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If you want to some basic ideas about that then you go for S k garg. And if you want to know deep knowledge about that then go for Metcalf and Eddy. It's clear all the concepts from basics to advance.
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Excess of fluoride content in drinking water (more than 1.5mg/L) sourced from inland water bodies causes dental fluorosis and skeletal fluorosis. Although reverse osmosis (RO), electrodialysis, and distillation are available for deflouridating inland water bodies. However am not sure that how effective these methods can be used to deflouridate groundwater. I would like to hear some suggestions on the mechanisms effective at deflouridation of groundwater.
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Deflouridation techniques are simple and can be explained like Bone charcoal, contact precipitation, Algona, activated alumina, ion-exchange technology, membrane filtration, nanofiltration, and clay are all methods for defluoridating water that can be used. Reverse osmosis (RO), electrodialysis, and distillation are examples of cutting-edge treatment methods.
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We are seek alternatives to Qual2kw in water quality simulation models based on R program. Present day, we use .xlsx based model. Our objective is calibrate/simulate water quality scenarios of river, with point/nonpoint sewage sources. Thanks a lot!
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Thanks a lot, Jochen Hack! Your answer is helpful.
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Have a nice day everyone,
I need historical N-P datasets to run my conceptual model whose diagram is attached. I'd be so glad if you could suggest any database and/or platform to access to water quality data.
Thanks in advance
Best of luck
İbrahim ERKOL
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for global nitrogen data please Ref:
A.Zhang 2021 .
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Some specialists use the electrical resistivity methods to determine the quality of groundwater. I see that we carry the method more than its ability... what do you see? Taking into account the difference between water salinity and water quality
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In fact, it is a complex situation. Without previous information from nearby boreholes, one can't be sure about the salinity of the groundwater. The presence of clay can lead also to a decrease in the resistivity values simailar (somehow) to the case of the presence of groundwater with relativly high TDS values. Water quility is another stroy :-)
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I want to predict water in my project. I need to know which of them have more advantages.
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A Bayesian network is a graphical model; it consists of a collection of random variables that are represented as nodes in a directed graph, with the graph's edges representing the variables' interdependence.
In theory, a Dynamic Bayesian Network (DBN) functions identically to a Bayesian Network (BN): given a directed network (the structure), you may learn conditional probability tables (the parameters) from a dataset.
The primary distinction is that a DBN reflects a time-dependent phenomena; therefore, whereas a conventional BN may have a node reflecting variable "A" influencing variable "B," a DBN may have variable "A" at time=1 influencing variable "A" at time=2.
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algae index , water quality
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Jasim m. Salman experts have already nailed it particularly the formula shared by Uthirasamy S. and the links of Avinash Kumar and Omar Farouk Al Mashhour are the best ones and I liked the links and the data shared about the ALGAL index estimation and the assessment of ecological status using the phytoplankton inices,,,Thanks
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I took a series of DO concentration readings at freshwater springs distributed over a large geographical area. Four weeks elapsed between the first measurement and the last. Each site was sampled only once. The DO concentration values of all readings are considerably lower than I expected.
All measurements were taken using a multi-parameter water quality meter from Hanna Instruments (HI-98194). Calibration was completed the day before the start of the sampling campaign.
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Hi Giulio,
Do you have DO in mg/l too? Saturation (%) is a relative measure moderated by temperature, i.e. the amount of oxygen present as a % of the max possible amount at that temperature. The groundwater DO might be very similar, but site-specific factors like presence of primary producers, shading or sampling factors like time of day, distance from the upwelling etc. may be influencing temperature, and thus saturation.
Best
Kieran
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Dear all,
I hope everyone is doing well,
Currently, I'm working on remote sensing of water quality with an emphasis on suspended sediments estimation. recently I'm going to use machine learning algorithms such as Random Forest, Support vector machine, cubist, convolutional neural networks in R to train and predict water quality parameters such as suspended sediments from satellite images.
I appreciate any help with providing R code with some explanations on this.
Thanks,
Abduselam
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First of all you need a data, loo for some proper dataset then you can apply preprocessing and machine learning techniques
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I am selecting an opensource hydrological model to perform a water sustainability assessment at a basin scale, including blue and green water sustainability evaluation and some considerations about water quality. I need an open source, well documented and user friendly open source software. After a first check, I identified two suitable options: SWAT+ and SWIM. I cannot really understand the differences among them. Any suggestion from someone who has already used these models? Thank you for your cooperation.
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I would recommend to use SWAT instead of SWAT+, it is a bit harder to use outside the US, but it's more reliable due to bugs in swat+ (as now, I hope It will change, as swat+ is has more user-friendly interface) - in example swat+ doesn't calculate properly urban CN (uses cn 98 value for permeable areas), overall results differ significantly from swat results using the same input (I didn't look for this bug, just gave up testing swat+).
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need to understand what it depicts
how to read dendrogram
how to make important inferences using this
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Thank you so much Ouarekh Mohammed
Neda Ravankhah
John Machell for your valuable answers
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I would be grateful if you could help me find out one or few case studies in the Pacific region where soil erosion in pineapple fields is efficiently managed.  As part of a regional project (www.spc.int/resccue) dedicated to integrated coastal zone management  in the Pacific region, I would like to identify few case studies where soil erosion in pineapple fields is correctly managed in order to organize a technical exchange between pineapple producers in French Polynesia and producers in other places of the Pacific region.
Many thanks for your answer.
Do not hesitate to contact me if you need further information.
Best,
Mr CHARLES mahe / RESCCUE project coordinator in French Polynesia
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This is a good question.
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I Have been so much overwhelmed by the parameters that needs to be adjusted in the .wwq input file, as i was reading the SWAT 2012 documentation , the most of the parameters are explained but, they need high level of expertise and time to collect all the necessary data to adjust them,
has anyone ever did adjust those parameters , if so share your expirience ,
or can i just run the model with the default parameters, then after calibration i could just use the data to represent the watershed ?
help iam just a novice in this model , i just want to model water quality
please be kind
thanks in advance
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That is a good question.
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I am thinking of using kits for extraction of DNA and other genetic materials from water
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PowerWater DNA extraction kit by MO BIO Laboratories Inc is very reliable, though it is very expensive. I have used it when other kits have failed
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Dear all,
Are there publications/guidelines about methodologies for identifying critical areas based on stormwater quality? I am especially interested in methods based on GIS analysis and water quality sampling. By sampling I mean quite practical approaches that municipalities can utilize while trying to map critical areas for stormwater quality management, and with city-scale focus. I assume that a city-scale project has to start with a GIS analysis of critical areas and then, as a second phase, continue with a water quality sampling campaing(s) of selected sites.
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One of my advisors once wrote:
I hope this may help in identifying key sampling sites.
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I am looking for someone who wants to research Kushiara River and Fish Deversity.
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Yes. I have experience of working with water quality.
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I want to get some water quality parameters (ideally dissolved oxygen, turbidity, chlorophyll, pH, etc.) inside oyster bags. The oyster bags are mesh (potentially a range of mesh sizes from 1 mm up to 25 mm or so, but most typically around 9 mm), and I'm trying to find out how water quality varies within these bags with, for example, stocking density. The bags are often 3' x 1.5' x 0.25 '
I'd like to sample these parameters without 1) having to put a datasonde in each bag (unless they are very cheap) or 2) having to open each bag.
In talking with YSI, there are flow cell chambers that enclose the probes and they suggested pumping the water into the chamber via tubing inserted into the bag through the mesh. As described, this would take a full liter of water (where the entire bag volume is around 40 liters, but is, of course, open to the surrounding water).
I'd like to draw the smallest possible amount of water to reduce the likelihood of drawing in water from outside the bag. I'm also open to entirely different solutions. Appreciate any feedback.
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In sampling water table at various depths, we epoxied a ceramic cup onto plastic pipe. We pressurized system using two hole rubber stopper and tubing to remove water, then used vacuum to withdraw sample, then pressure again to force sample through the longest tube from the ceramic cup. This approach was used by Sopper and Kardos from Penn State in sewage irrigation studies in the 1970s. I am not sure how well our co-authored report in 1975 with Tennyson and Settergren explained this, but most likely we cited the Penn State study.
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Most of the developing countries extract water from the shallow water table for drinking and other activities. Pit latrines/toilet pits and drinking water wells are located in the same land in such countries.
Safe distances between wells and pit latrines are varied from location to location depending on the soil type, hydrogeological condition of the ground, and the elevation of the toilet pit. In practice, this distance varies from 15 m to 30 m in accordance with guidelines provided by the local authorities in developing counties.  Viruses are very small compared to other microorganisms so that they can be pass through the porous soils easily.
Behaviors/stability of Coronavirus in the shallow water table are being studied. I would like to discuss this matter with the latest findings.  
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Dear A. G. Piyal Aravinna,
Yes, this is an important issue that should be taken into account when improving anti-pandemic safety instruments and systems. The key issue is the distance, but also the creation of such anti-pandemic and sanitary safety instruments that will ensure full separation of water intakes from sewage systems, etc. The issue of distance should take into account various possible technical and organizational devices that will ensure an appropriate range of social distance for citizens and thus the possibility of epidemic development will be much smaller. What do you think about it? What's your opinion on this topic? What do you think about this? What do you think about this topic? What is your opinion on this issue?
Best wishes,
Dariusz Prokopowicz
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I am looking for different types of aerators and aeration equipment that can be used in reservoirs.
Any help in this regard is appreciated.
Thank you.
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Aeration is the process of absorbing oxygen from the air is known as aeration. High amount of O2 is provided in the aeration tank because of the high BOD in sewage. This cannot be provided naturally therefore aerators are used to provide O2 artificially. When the dissolved oxygen level (D.O) falls below 2mg/l anaerobic activities start. There are three methods for aeration in the activated sludge process: (1) Diffused air aeration; (2) Mechanical aeration; (3) Combine aerator.
(1.) Diffused Air Aeration. In diffused air aeration method compressed air is blown through the sewage and air is diffused in sewage by diffuser. Diffusers are of two types: Plate diffuser and Tube diffuser.
-Plate Diffuser: They are rectangular/square plates made of crystalline alumina or high silica sand. In this method, the compressed air is blown through a perforated plate diffuser. The air comes out through the holes of the diffuser plate and rises upward in the form of bubbles. Thus the sewage absorbs oxygen from the air.
-Tube Diffuser: It consists of a perforated tube suspended in the wastewater, near the bottom and can be taken out while cleaning. The compressed air is dent through the tube. The air comes out through the holes with great force and agitates the sewage.
(2.) Mechanical Aeration
In this method the surface of sewage is agitated violently with the help of some mechanical equipment to encourage absorption of oxygen from atmosphere. There are two well known forms of mechanical aerator. Vertical surface aerator and Horizontal surface aerator. They consist of electrically driven propellers (vanes) mounted in either a floating or fixed supports. They throw the bulk liquid (sewage) through air and oxygen transfer occurs both at the surface of the droplets and at the surface of the bulk liquid and is then mixed by the currents produced by agitation. In this method the performance is seriously affected by ice formation in winter.
(3.) Combine Aerator: In this system, diffused air aeration and mechanical aeration are combine in a single unit. The well known type of such combination is Dorroco aerator. The aeration of sewage is done by air diffusers as well as mechanical aerators. Air diffuser plates are located at the bottom of tank and the submerged paddles rotate in the direction opposite to that in which the compressed air rises up from the air diffusers. Paddles are rotated by a motor on a horizontal shaft with a speed of 10-12 rpm.
Advantages of Combine Aerator: Aeration is very efficient; Detention period is reduced (3-4 hrs); Quantity of compressed air required is less as compared to the diffused air aeration.
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If you are working in the Great Lakes especially in Areas of Concern (AOCs) we have a project that we are working on. This research project is to study the economic impacts of remediation and restoration at Great Lakes Areas of Concern. The research participant will conduct research collaboratively with ORD staff and the Great Lakes National Program Office (GLNPO) of EPA's Region 5 office. This research will apply a variety of economic approaches (e.g., both market and non-market valuation such as from I-O modeling, hedonic models, and benefit transfers) to quantify the benefits and costs of remediation and restoration projects in Great Lakes Areas of Concern (AOCs). The research participant will collaborate with a multi-disciplinary group of individuals including but not limited to water quality modelers, engineers, economists, ecologists and social scientists evaluating remediation, restoration and revitalization (R2R2R) outcomes that are central to attaining Sustainable and Healthy Communities. The R2R2R framework was developed by ORD & GLNPO to help fulfill Great Lakes Water Quality Agreement commitments “to restore and maintain the chemical, physical, and biological integrity of the Waters of the Great Lakes.” Potential endpoints of analysis include improved water quality, restored designated uses, and/or ecosystem services.
If you or anyone you know that is working on a similar project please contact me at:
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Dear Dr James; Thank you for a great question; as we know protected areas, and nature conservation generally, provide many benefits to every society, including preservation of biodiversity, or maintenance of watersheds and .....
Recently I read some valuable articles/ Thesis about on this subject and would like to share them with you.
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How often should I clean it, is it every 6-months/yearly?
Is this protocol right for cleaning?
1st Time we got this water distiller I use salt lemon 0.5 Kilio & turn on the device for 3 hours (twice) & wash it very well with tap water and turn it on for the 3rd time to clean it from any remaining salt lemon.
How often should I test the water quality is it every 6-months/yearly or every time after cleaning?
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Every two weeks to get rid of the scales.
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I have a water quality data set ( Fecal Coliform). This dataset includes right-censored values ( >600), left-censored values (<10), and non-censored values.
Which non-parametric test I can use instead of Kruskal Wallis test followed by multiple comparisons to compare more than two groups?
Can I use Generalized Wilcoxon Test ?
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Another set of R packages are the NADA and NADA2 packages which address censored data. Unfortunately, I am not sure that they address left- and right-censored data at the same time.
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Globally, there are more than 45,000 large dams in operation in over 150 countries and another 1500 or so are currently under construction according to World Wildlife Fund (WWF). Dams and weirs have been built on rivers (a barrier across a river) to achieve a number of benefits including water storage, irrigation supply, drinking water, preventing floods, navigation, hydroelectricity production, and recreation etc. In recent time, most dam construction is taking place in the developing world, such as in China and India. 46 new large dams being planned or under construction in the Yangtze River basin in China; 27 in the La Plata basin in South America; 26 in the Tigris and Euphrates Basin in Turkey, Syria and Iraq. Dams are also planned on three other rivers: the Salween in China, Thailand and Myanmar, the Kizilirmak in Turkey, and the Ganges in China, Nepal, India and Bangladesh.
The development of engineering infrastructure such as dams and weirs over rivers has modified rivers ecosystems threatening the water quality (e.g. salinity, cold water pollution) and water dependent biodiversity (e.g. native fish). Dams disconnect rivers from their flood plains and wetlands, reduce water flows in rivers, and affect the migratory patterns of fish. In general, water retention by dams eliminates or reduces spring runoff or flood pulses that often play a critical role in maintaining downstream riparian and wetland ecosystems including the lifecycle of fish. Older dams release water that is stored at the bottom of the dam, which is typically colder and adversely affects species adapted to warmer temperatures. Such an effect is sometime referred to as ‘cold water pollution’. The construction of a dam on a river can block or delay upstream fish migration between feeding and breeding zones and thus may contribute to the decline and even the extinction of species. As a consequence of dams, for example, some unique species and habitats are/will be threatened including freshwater native fish, river dolphins, porpoises and water birds. One estimate reveals that dams and associated uses of water have altered two-thirds of the world’s major rivers.
In Australia, the Federal Government Department (Commonwealth Environmental Water Office) has acquired/is acquiring water with the goals/objectives to increase water flows in rivers and wetlands (commonwealth environmental water). Reduced flows in the Murray Darling Basin (MDB) have already caused environmental problems (increased salinity, increased algal blooms/cyanobacterial blooms, decline in native fish and bird populations and poor wetland health). This environmental water has been/is being recovered through water saving infrastructure upgrades, water purchases (direct buybacks of water entitlements from irrigators) and other water recovery programmes in order to protect or restore the environmental assets of the MDB. The environmental water will help protect and restore the resilience of the MDB’s rivers, wetlands, floodplains, lakes and red gum forests, together with the plants and animals that depend on them. In a number of countries (e.g. third world countries), people may not be familiar with environmental water or environmental flows and a need for environmental water for biodiversity.
Question: Do you agree that there is a need for environmental water/environmental flows to protect biodiversity where dams have been built or to be built? If so, how can we achieve a balance between water usages for consumptive purposes (drinking water, industry and irrigated agriculture) and meeting the demand for environmental flows for smooth functioning of river ecosystems and river biodiversity?
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You raised a very important question.
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In water quality assessment, the presence of Pesticides and various organic compounds( including emerging contaminants ) will have a deeper impact on human health and the environment. Even usage of the highly sophisticated HPLC, LC, Methods will also have the financial constraint for the researcher in low-income countries due to lack of funds. Hence What are other alternative methods that would give information on the concentration of the pollutants?
Can a biosensor be utilized?
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Dear Colleague
I understand your situation!
If the accuracy and precision of analysis and results are important(that I am sure they are so dominant in analytical chemistry), there would be no way, and please try gas chromatography (GC) and high-performance liquid chromatography (HPLC), but probably the sponsor from RG or other opportunity will be provided for you.
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I am a novice researcher, and i'm working on a project which is busy analyzing water quality data from different water sources such as dams,rivers, and springs , and also from secondary sources such water treatment plants, and households, i have collected water GPS coordinates, which appear on the image* , hence im having difficult to find the right methodology to analyse these results spatially. The microbiological parameters that are going to analysed include bacteria such as E.coli, salmonella spp , Shigella spp, Giardia spp, Entamoba Histolytica spp.
please help and be kind :)
i have attached an image showing the sample locations , additionally the study area is in six Quaternary drainage basins
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We have the hatchings of Batagur Dhongka at the Rescue and Rehabilitation Centre. They are healthy and growing well, but the problem is that algae have been found on their carapace. We used to remove it manually, and the algaes are coming back next month. The water quality/aeration is perfect. We are changing it twice a week. We have other species as well, like Batagur kachuga, and they have never found these algae. Would you please tell me some tips on how to remove algae from the Batagur Dhongka carapace permanently?
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Animesh Talukdar Bernardo Antonio Perez Da Gama Kiprotich Kiptum Thank you for your suggestions. I will look into it.
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Please, can you suggest a high graphical resolution software for creating hydrogeochemical graphs, especially for Gibb's diagrams?
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Much chemical process modelling and/or simulation work can be done with the widely-used Microsoft’s Excel.
Application example ― Simulations carried in Excel 5.0 with Visual Basic for Applications (VBA) macros ― The recursive least squares algorithm (RLS) allows for (real-time) dynamical application of least squares regression to time series. Years ago, while investigating adaptive control and energetic optimization of aerobic fermenters, I have applied the RLS algorithm with forgetting factor (RLS-FF) to estimate the parameters from the KLa correlation, used to predict the O2 gas-liquid mass-transfer, while giving increased weight to most recent data. Estimates were improved by imposing sinusoidal disturbance to air flow and agitation speed (manipulated variables). The power dissipated by agitation was accessed by a torque meter (pilot plant). The proposed (adaptive) control algorithm compared favourably with PID. Simulations assessed the effect of numerically generated white Gaussian noise (2-sigma truncated) and of first order delay. This investigation was reported at (MSc Thesis):
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We are setting up a water filtration system for our bivalves hatchery, the water should be pristine (clear) & clean for to be use in operation.
Seawater was pump directly from the sea, into our sedimentation pond (earthen), then pump into the holding tank in the hatchery that undergo filtration via sand filters.
The water have a slight yellow tint, the colour is very obvious in large volume. Hence, we thought to remedy via chlorination (domestic Clorox) and ozonating the water.
But, instead of purifying the water, it became more orangey-tint, and it stained the water container.
suspect for high concentration of irons, so sent the water from both pond and hatchery for analysis, but the iron level is normal (0.03-0.06 mg/L)
any expert or experiences individual know what/why this occurring and how to remedy the problem?
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O3 should help you to solve the problem. If not, try H2O2
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Recently, our group collect water quality samples at several rainfall event, however we only get 8 samples which isn't enough to run the LOADEST model. Based on simple test about this data, we find a pretty good linear trend, so can I select model 1 and 2 or user predefined formula to predict the load of this event ?
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You may be able to fit the LOADEST but the model will not be reliable. See our paper on LOADEST:
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I need an assistance using GIS and RS in mapping out surface water quality parameters? I have downloaded the RS images for my study area.
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Hi, consider taking a look at this article where we used surface reflectance values of different Landsat TM bands to correlate with insitu Surface Water Salinity values (in Florida Bay area) and developed a statistical model. The geographically weighted regression showed promising results.
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Hi
I need to know the limits of pH, TSS, BOD, COD, temperature, and other effluent characteristics for direct discharge into water bodies in the US and European Union standards.
Any help in this regard is appreciated.
Thank you.
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Hi. I suggest for you the following report that could help you:
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I am currently working on coastal water quality assessment. I need the impacts of SST on tropical cyclone formation and its related processes.
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Its very much related because cold water transfer to warm water area. As a result upwelling occours. Surface water very much related to upwelling.
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I am currently advising a young student in the National University of El Salvador and he has an interest in working with remote sensing data to study freshwater quality (turbity, pollution, algae blooms, etc). The available data to use is the Copernicus/Sentinels open data from the European Space Agency. The university periodically conducts in-situ studies of the water and collects samples along with the National Ministry of the Environment and Natural Resources.
We think that exploring the correlations between temperature, suspended matter, clorophyll (algae) and data from Sentinel 2/3 (some initial exploration attached). But this is just a very initial/raw idea.
Therefore I would like to be advised on relevant topics in this field of research that are of interest to the global community and not just El Salvador. My ambition is to conduct a research task that can be contributed to international peer-reviewed journals and establish relationships with experts and research groups abroad.
Any suggestions, ideas, contacts will be greatly appreciated.
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Hola Napoleón, actualmente la UCA desarrolla una investigación interdisciplinaria con biólogos, expertos SIG en teledetección y expertos en ciencias de la computación, en un proyecto de monitoreo del crecimiento de algas y toxinas en el embalse del Cerrón Grande, puedes contactar con Metzi Aguilar que coordina la parte de teledetección maguilar@uca.edu.sv y Luis Cierra biólogo jsierra@uca.edu.sv , creo que pueden tener buena sinergia!
Saludos
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Hello all,
i am new to water chemistry, i have been looking at trends in the water chemistry parameters, and found there is significant decreasing trend in Stream-water temperature, Ca, Mg, Na, and chloride along with discharge both in the monsoon and non-monsoon seasons.
Like From Jan 1994, Jan 1995, Jan 1996...... Jan 2018 (for Non-Monsoon period) Sept 1994, sept 1995, sept 1996...................Sept 2018 (Monsoon period)
Note- watershed (1000 km2 drainage area, Western Ghats, India) is free from dams and other water structures.
What could be possible drivers of trends in the above parameters?
Please provide your valuable suggestions.
Thanks in advance.
Regards
Rajat
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A couple of my earliest Researchgate entries and citations may be informative, even though different conditions. Many water quality parameters have influence from flow rate (discharge), and in part often due to rainfall dilution effect, runoff and movement of sediment and other non-point pollutants and nutrients during storms. You may find a hysteresis effect with markedly higher values during rising limb of hydrograph, and lower rates as hydrograph recedes. Geology and groundwater and its chemistry influences contribute to varying degrees as some streams loose water to groundwater, while others gain water inputs from groundwater for substantial periods of time. There are many books and papers on the subject, as well as professional or informational courses. It is not unusual to find these trends. Stream temperature in many locations increases in the summer growing season as more solar radiation, higher temperatures with lower streamflow often combine to elevate temperatures. Streams heavily augmented by groundwater or springflow as well as dense forest cover have substantially less effect than conditions without these benefits. In one of my studies, mountain streams without dense forest cover actually had lower winter temperatures, so forested stream buffers may have a moderating effect on temperature extremes in both summer and winter. It is highly useful to have recording water levels to estimate flow rates with time. A relative moderate expense tool for this is transducer (vented or barometric adjusted unvented). Streams with excessive sediment may contribute to transducer fouling, but properly installed, they can collect high quality data for weeks or months without service. The USGS collects flow data every 15 minutes, and appropriate for your study area. For small catchments, more frequent readings may be needed. A variety of tools or techniques are available to collect samples during storms or more routinely, if ample research funding exists.
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In my study area, water quality data is scary at some period because we don't have automatic machine. But I wish to use limit data to analysis concentration-discharge hysteresis and normalized cumulative load plots.
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Hi everyone,
I have 8 water quality parameters to explain the herbivory rate of sea urchins in seven different sites (80 observations in total). I have done a multiple linear regression and results showed that several parameters are significant drivers for herbivory rate.
I have also done an RDA on sea urchin abundance vs water quality (both multivariate) and visualized it, but somehow I am confused on how to visualize the herbivory (univariate) vs water quality. Is it still possible to do an RDA on this type of data? I understand I can make a residual plot of the regression, but I'm wondering if I could still have ordination arrows on the plot for herbivory vs water quality.
Many thanks, hope the description is clear enough to understand. I appreciate any feedback and suggestions.
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Before you do the RDA, you should check the length of the extracted gradients using a DCA, then decide whether you should perform A CCA of RDA. For MLR, I think you have few observations (8 sites) for the many water variables you mention. You instead consider the more flexible PLS (Partial least squares projection to latent structures) MLR to avoid overfitting your data.
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What would be the methodology of this work and how should I conduct this research?
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Climate change needs data for a long period say 30 years.
The methodology is
Desktop study of water quality of rivers as well as rainfall in a certain portion of a river in your region.
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After getting my cyanobacteria-water samples, filtering them through GF/F filters, and freezing-thawing them, I use the trichromatic method to get Chl-a concentration.
I am wondering how much "free" (not cell-associated) chl-a is passing through the filter? is it possible to measure that portion that stays in the filtrate? If so, how would I do it?
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Dear Kelly,
the quickest and easiest (but still with high sensitivity) would be using a plankton fluorometer. Most of these will also provide an estimate of phycocyanin and phycoerythrin, which might be useful for your cyanobacteria-related question.
Good luck
Marco
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I am running a nonlinear regression model for water quality parameters. What is the best way of selecting predictors for the regression model and is it good to use many predictors in the regression model?
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Do you deal with estimation or prediction issue. In case of prediction issue, you can just evaluate prediction accuracy from different specification. In case of estimation, you can run LASSO regression - it will shrink the variables with lowest contribution to the model.
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Can I change Guidance (CCME 2004) canadian in
For example, I use the standards of the W orld Health Agency or the Indian Agency of Health?
Can I change the sheet excel (Guidance) and work on it?
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CCME is the same as WHO, There is no harm in changing your excel files. If you need help you can let me know through RG.
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It has become necessary that such sensors be present in fish farms to maintain water quality and control the spread of disease
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Some good reference you can refer:
Remote Sensing Techniques to Assess Water Quality
  • Photogrammetric Engineering and Remote Sensing 69(6)
  • DOI: 10.14358/PERS.69.6.695
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Hi,
I did some analysis to compare diatoms obtained from streams and explain their relationships (water quality). Like SIMPER, ANOSIM, PCA, cluster. What other analyzes would you recommend? Thanks..
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Can you send me a sample of the data matrix you prepared for use in R? If I can see the preparation of the matrix (what are the rows and columns) I can do these analyzes in R.
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I am doing master so that I need suggestion this is my topic for research
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thanks for suggesting sir
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What are the challenges and obstacles that we may face in modeling water quality in urban catchment ?
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The concentration and dilution nature of various chemical industries in the town that discharge waste into the rivers.
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Hello
I have in-situ data of a "water quality parameter" in 2013 and need to predict data for 2019. I have found an index (regarding the spectral characteristics of the water quality parameter) that is calculated from Landsat images in 2013 and then calibrated with in-situ measured data showing R2 ~ 0.7.
Now I have the index calculated from Lansdat for 2019, and the question is how possible is it to get corresponding water quality data from the index, considering the calibrated formula I have from 2013???
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The linear correlation between the field data and the remote sensing data must be constructed via regression analysis. After extracting the new model, it may be applied to any image at any time according to such criteria.
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The attached below explains this question.
All comments respect
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The age old drinking water quality vs. quantity debate rages on, even as sanitation and hygiene are being promoted intensively.
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Good water quality reduces incidences of water borne diseases. The money that would have been used to treat diseases can be used for other economic purposes.
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Can trend analysis methods be applied to water quality data?
Trend Analysis Methods: Mann-Kendall, Sen's T Test, Spearman's Rho Test, ITA, ITTA and IPTA
Water Quality Data: Daily, Weekly, Monthly and Yearly
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Can the geology of an area have an effect on the quality of water that drains through it?
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Yes of course the Geology has it effect on the quality of water while it moves through an aquifer area of recharge to discharge and from precipitation when it infiltrates the soil due to the geological material difference on the physical and chemical properties like chemistry and composition, texture, grain size, age, and natural processes.
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Models that evaluate parameters to water quality. For example clorofila a, turbidity, DO, etc.
Models for lakes in the tropical zone.
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Six main public domain water quality models which are presently available for Rivers and streams are being captured in this article. These main models could produce important results if they are used in the correct manner, because they are different in terms of assumptions, strength and weaknesses, processes they represent, modeling capability and data input requirements. The Model review discussed includes, water quality analysis simulation program (WASP7), simulation catchment (SIMCAT), quality simulation along Rivers (QUASAR), and the temporal overall model for catchment (TOMCAT), QUAL2KW, QUAL2EU. The models are described individually according to a consistent set of criteria-conceptualization, model capability, model strengths, limitations, input data and how it utilized. The outcome showed that TOMCAT and SIMCAT are important in ASSESSING effect of point sources in a very simple way. The QUAL2KW, unlike the QUAL2EU where macrophytes play a major interaction, it can convert algal death to carbonaceous Biochemical Oxygen Demand (CBOD), thereby making it more suitable. In addition to the extensive requirement of data, it is expensive and time consuming to set up these complex models such as QUASAR and WASP7. Therefore, one model cannot be used for all the required functionalities. Choosing a model would depend on a specific application, financial cost and time availability. This article may be of help in choosing a suitable model for a specific water quality problem.
Article Water Quality Model for Streams: A Review
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Water pollution occurs when harmful substances often chemicals or microorganisms contaminate a stream, river, lake, ocean, aquifer, or other body of water degrading water quality and rendering it toxic to humans or the environment. What are the environmental effects?
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The affected fish (O. niloticus) are three months old. The infected fish were taken for a public display after which this infection started. Water quality parameter for the tank where the fish were stocked are as follows:
D.O. - 6.3 mg/l at 86% sat
Temperature - 25°C
Ph - 8.25
The infection was observed to start from blinding one eye then spread to the other, then the fish stops feeding and dies. The fish died after two weeks from the time of the first observation of infection.
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I following the best answer.
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What are the better remote sensors models to use to monitoring water quality?
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I have successfully used Climgen (University of East Anglia) to study regional temperature climate projections after downscaling analysis in GIS. There are other climatic variables available under Climgen also.
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Are there particular impacts on aquaculture?
Also, how does the increase in zooplankton abundance correlate with fish population? Is it also somehow related to the effects of eutrophication?
Will highly appreciate your response on this matter. Thank you so much and have a great day!
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Hi Kathleen,
With a high population density of plankton-eating fish, ie with an unbalanced fish stock, large species of zooplankton, especially daphnia (Daphnia magna, D. pulicaria), disappear, we take them here as a component above 0.7 mm, which have the greatest predation pressure on autotrophic organisms. Instead, a small zooplankton (D. galeata, D. longispina, etc. and the genus Bosmina) may multiply, the predation pressure of which is limited by size. On the other hand, even with the presence of large daphnias and at the same time sufficient nutrients, especially phosphorus, those species of autotrophs that are unable to filter out can and often do occur. These are algae and cyanobacteria that form colonies, cenobia or fibers, but do not form vegetation turbidity. Therefore, even after the revitalization of stagnant waters, when the supply of nutrients from the basin is not solved - fish, wintering, siltation, cyanobacteria can develop into water flowers, so the top-down effect may not work. With increasing predation pressure of fish, the share of other groups, mostly small, zooplankton - copepoda, rotatoria - also increases. However, the main cause of eutrophication is the excessive supply of nutrients, especially phosphorus, inland waters. In general, however, it is a complex problem.
Today, 15.12., Temperature 3 ° C, I found the evident development of cyanobacteria in the highly eutrophic waters used as fishing grounds, while the water looks clean and transparent with good transparency.
Emil
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I'm studying the relationship between aquatic insects (as biomonitoring medium) and water quality of river. I only have the data for the number of insects/organisms based on their respective orders (ephemeroptera, plecoptera, diptera, odonata). I haven't got the information of what family they are in, so I could not calculate the actual tolerance value for each order of insects.
Is there any alternatives, modified biotic index formula or any other indices that can be calculated using only these information that I have?
Feedbacks are highly appreciated.
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Hi, the question has many aswers depending of what do you want to recieive as an output of calculations - assessment/evaluation of the quality of water environment or the benthic communty itself. To use any method based on species you need to know their (of each!) ecological tolerance/resilience according to the basic ecological principles of Shelford. In case you have not possibility/capacity to use species related indices, you may use EPT-index based on three main insect orders - Ephemeroptera, Plecoptera and Trichoptera. There are also community related indices such as Shannon-Weaver's species diversity index, Pielou's equitabilyty index, Simpsom's domination index, Margalef's diversity index, etc., which all have not so strong requirement to know species' latin binoms, it's enough to recognioze species A from species B and C, etc... and based on these "species list" to calculate indices. This was practicized for years in official state water/river monitoring in my country.
I'm sending a chapter of mine in the university text-book on Biogeography with some more explanatkions on the topic.
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Greetings,
I am looking for a standard procedure for determining the bulk reaction rate to undertake a water quality (constituent) analysis.  I understand from the AWDM book and other literature that the procedure entails sampling water from the source through bottle tests and making chlorine tests every day and plotting the results on a semi-log chart to get the bulk reaction rate value.  However, I need a detailed standard procedure with step-by-step instructions to send to the lab so that they make the tests accordingly and come up with the results.  I have made my research online and could not get hold of such a document.  I would highly appreciate your help in that regard.
I would also appreciate any help regarding any empirical equation to determine the wall reaction rate, as I understand that it depends on specific factors such as pipe material, age, and other such considerations.
Thanks and best regards,
Am