Science topic

Eutrophication - Science topic

The enrichment of a terrestrial or aquatic ECOSYSTEM by the addition of nutrients, especially nitrogen and phosphorus, that results in a superabundant growth of plants, ALGAE, or other primary producers. It can be a natural process or result from human activity such as agriculture runoff or sewage pollution. In aquatic ecosystems, an increase in the algae population is termed an algal bloom.
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For instance, i want to use the IPCC 2013 method for the impact category climate change, but use Usetox for ecotoxicity and CML-IA baseline 2013 for eutrophication and resource deplition (fossil fuels). Is this possible? How do i make a method that incorporates all the different already existing methods?
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Dear Sofia,
the CML 2013 impact assessment method also takes ecotoxicity into account, I know. Why do you want to combine impact assessment methods? From a professional point of view, I would like to ask this question because I am interested, I do not want to argue, of course. Best wishes, Viktoria
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Hello.
I am studying the variation of nutrient content (especially N and P) in an eutrophicated hypersaline lagoon in Brazil. I would like to better understand the electrochemical behavior of nutrients in water column and/or sediments. This lagoon presents very high oxygented waters, but its sediments exhibit very reducing conditions. If anyone has any suggestion for this issue, it would help me very much. Thank you all.
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I suggest you to carry out some work on sediment oxygen demand (SOD), pore water chemistry (both metals along with P and N), speciation of metals and finally measuring Eh (ORP) of both sediment and pore water. You will get a clearer picture of the aquatic environment that you are working on.
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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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I am trying to remove phosphate from wastewater sample and also recover them. Is there any material that only absorb phosphate from water? Therefore, which natural material should be appropriate to use as absorbent?
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Tamjid Us Sakib depends on the type of technology selection and project
microlage is preferred in case of biological and if you have space and time with low cost investment however if you go via chemical route there are many like activated carbon, haaluminum sulphate or few other sales can also be used
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Dear colleagues
I have a query regarding the most appropriate experimental design and statistical analysis for a research project. The project study area is located in a high altitude lagoon (Los Andes, Peru). The study subject is an endangered frog species (the Lake Junín frog).
The research question is: What is the impact of heavy metals, eutrophication and water level variation on the abundance and biomass of the Telmatobius macrostomus and T. Brachydactylu population?
After many field visits and literature research we've found out the 3 main environmental pressures on the frog population: (i) heavy metals from mining activities, (ii) eutrophication produced by untreated urban sewage discharge and (iii) water level variation to assure enough water for hydropower downstream. We have monitoring data (from secondary sources) on heavy metal concentration and some eutrophication indicators (N, P, DBO). For now we only have the resources to collect field data on water level variation, and the frog's biomass and abundance.
Currently we don't have resources to collect more data on heavy metal pollution or nutrient content in the water. Therefore, with the available data, we want to have some idea on what are the most relevant environmental pressures to:
- Know where to allocate more resources on monitoring and
- Evaluate some remediation techniques to improve the frog's habitat.
Thanks in advance for your comments.
ps. Feel free to contact me if any of you are interested in helping designing the study.
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Dear Dalia, Kindly follow the references, although I think you need more papers for comparing the contamination and pollutions, by the way , you can ask me to send other articles for your discussion part!
Anyway, hope they would be helpful:
1- Distribution and Accumulation of Heavy Metals in Surface Sediment of Lake Junín National Reserve, Peru; Available online:
and it is in research gate !
2- The heavy metal contamination of Lake Junín National Reserve, Peru: An unintended consequence of the juxtaposition of hydroelectricity and mining
3- The History of Mining in Cerro de Pasco and Heavy Metal Deposition in Lake Junin Peru ( it related in 2012 and I attached it)
4- Protected Area Profile Perú Junín National Reserve ( It has been attached)!
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Could we have at least 3 techniques of how to reduce the toxic nitrate impact in soil? Alternatively sustainable solution for Nitrate Vulnerable zone.
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Eutrophication can be mitigated also through conservation approaches both at the microscale and macroscale. For example at the micro scale (Household, farm, local community) eutrophication can be controlled through the design of constructed wetland in alternative to sewage systems for the management of human/animal waste. At the same level (micro) the construction/restoration of buffer zones adjacent to creeks and rivers will limit the loss of nutrients from cultivated fields that end in fresh water sources, on their way to the sea. Agroforestry has a vast body of literature about this topic. At the macro level instead we need to conserve, or restore wetlands along coastal zones as these will retain and metabolize nutrients contained in sediments by the plant community in place, while also increasing the water absorbing power brought to land by tropical storms and hurricanes.
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  • The chloride anion (Cl-) has traditionally been considered a harmful element for agriculture due to its antagonism with the nitrate anion (NO3-), and its toxicity when it accumulates in high concentrations under salinity conditions. On the other hand, Cl- is an essential micronutrient for higher plants, being necessary in small traces to fulfil a number of vital plant functions such as: cofactor of photosystem-II and some enzymes; neutralisation of positive charges in plant cells; and regulation of the electrical potential of cell membranes. Below a specific level in each species, plants suffer symptoms of Cl- deficiency, altering these cellular mechanisms and negatively affecting the capacity for cell division, cell elongation and, in short, the correct development of plants. However, there are indications in the literature that could suggest beneficial effects of Cl- fertilisation at macronutrient levels.
  • The results of my thesis have determined a paradigm shift in this respect since Cl- has gone from being considered a detrimental ion for agriculture to being considered a beneficial macronutrient whose transport is finely regulated by plants. Thus, we have shown that Cl- fertilisation in well-irrigated plants promotes growth and leads to anatomical changes (larger leaves with larger cells), improved water relations, increased mesophyll diffusion conductance to CO2 and thus improved water and nitrogen use efficiency (WUE and NUE, respectively).
  • Considering that the world's population is expected to reach 9.8 billion people by 2050, global efforts are being made to increase food resources by improving crop productivity. This requires practices that make rational use of available resources, particularly water and nitrogen (N). Only 30-40% of the N applied to the soil is used by plants, and 80% of available freshwater resources are currently being consumed by agriculture. On the one hand, an excess of NO3- fertilisation in crops leads to an increase of NO3- content in the leaves of plants of different species that are consumed fresh (e.g. spinach, lettuce, chard, arugula). The presence of high levels of NO3- in food can cause health problems such as methaemoglobinaemia or promote the accumulation of carcinogenic compounds. These practices also lead to an increase of percolated NO3- in aquifers, causing environmental problems such as eutrophication.
  • In broadleaf vegetables, NO3- and its derivatives can accumulate to high concentrations. When ingested, these compounds are processed by enzymes found in saliva and from bacteria of the gastrointestinal microbiota, generating NO2-, nitrosamines and/or N2O5, substances that promote stomach and bladder cancer, causing a serious problem for human health. When NO3- enters the bloodstream, it transforms haemoglobin into methaemoglobin, no longer able to transport oxygen to the lungs, causing babies to suffocate and die, which is what is known as 'methaemoglobinaemia' or 'blue baby disease', and which, as we have already mentioned, was made visible by Greenpeace on numerous occasions. Thanks to these actions, in the European Union there is a very demanding regulation of NO3- content in water for human consumption, as well as in vegetables and processed foods especially dedicated to the production of food products for susceptible groups such as babies, the elderly, vegetarians and vegans. Thus, the European Union has established a series of strict standards (1881/2006 and 1258/2011) that determine a series of thresholds for NO3- content in the most widely consumed vegetables (such as spinach and lettuce), and especially in baby food with much stricter limits, where it is even recommended to avoid the consumption of certain vegetables in babies before the first year of life and to limit their consumption in children from 1 to 3 years of age. At the environmental level, the European Union already created in 1991 the Nitrates Directive (European Directive 91/676/EEC), to protect water quality throughout Europe, encouraging the use of good agricultural practices to prevent NO3- from agriculture from contaminating surface and groundwater.
  • Substituting certain levels of NO3- for Cl- in fertigation solutions can reduce these problems without negatively affecting plant development. On the other hand, in the context of current climate change, the strong demand for water from agriculture threatens the freshwater supplies available to the population. Therefore, increasing WUE and NUE, as well as preventing water deficit and increasing water stress tolerance in plant tissues are very important traits for crops that could be favoured by the use of Cl- in new agricultural practices. Thus, Cl- could establish a synergistic improvement in a more efficient use of water and nitrogen for a healthier and more sustainable agriculture.
References:
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A very good explanation and cautions for those who are dealing with plant nutrients including myself. Yes, chlorine is the most ignored micro-nutrient!
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Hello, everybody. My PhD research is about eutrophication
processes in a hypersaline lagoon which has registered episodes
of fish mortality. My study includes a phytoplankton species
inventory. I would like a guide of toxic and/or potential harmful
phytoplankton. Thanks to all.
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Thank you Mohamed Ben-Haddad . :)
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Hi Folks,
You know that most of the European Countries including UK are in NVZ, and therefore could you please give some idea for longer term how could we reduce Eutrophication / toxic effect from those NVZ?
Thank you!
Dr K M Rahman
Research Fellow and Lecturer (BCU)
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I need some help with one observation of mine. I observed a pool of water full with algal blooms. The algal blooms of the pond appeared red in the afternoon but in the evening it turned green. What could be the possible reason behind this?
Thanks and regards
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Some green microalgae species have the protective red carotenoid for high light intensity during daytime (sometimes because of the nutrients content in water like salinity increasing when evaporation take place). When the microalgae get into the ideal condition, they will be in healthy green colour again.
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The eutrophication of groundwater by nitrate leaching is major environmental problem in Germany, especially in areas with intensive agriculture and high N-fertilizer inputs. In addition there are different regional aspects (like soil properties) which make certain areas more vulnerable than others.
I am currently working in a project where we want to improve the sustainability of crop production systems in Germany. Here, we want to assess the impact of crop production on various environmental areas such as GWP, Acidification and Eutrophication, using LCA’s.
We are working with Gabi-Software, which is why we are limited in the choice of LCIA-methods.
I had a closer look on the methods CML 2001, Environmental Footprint 3.0 and ReCiPe 2016 and their underlying models.
I understand the differences between the models. But if we want to assess the impact of Nitrate leaching on groundwater via LCA, it seems only CML is the appropriate method because it considers both - N and P emissions. Also, the characterization factor in Gabi-Software is an average European factor (For ReCiPe it’s a global, for EF it’s European too).
On the other hand, the CML-method is often described as a simple method, since it is a stoichiometric calculation of the contribution of N- and P-emissions to algae growth (Redford-equation). By this, it does not consider any environmental fate.
ReCiPe 2016 or EF 3.0 however differentiate between marine and freshwater eutrophication, in which only N- or P-emissions are considered. So, if I want to assess the impact of N-emissions to groundwater with ReCiPe, I have to use marine eutrophication. But would my results be valid for groundwater at all? The fate factor calculates up to the marine end compartment, and I expect large losses of emissions on the “path” between groundwater and seawater.
I find it extremely difficult to decide, as it is so important to estimate the effects as accurately as possible. Has anyone carried out a similar study on this subject and / or can give me a recommendation?
I would be very grateful!
Best regards and stay safe,
Pia
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Life cycle assessment (LCA) was originally developed as a site-independent tool, where the environments affected by the assessed impacts represent average or generic recipients. For all impact categories where the impact is dependent on the activity location, spatial differentiation can be highly important to achieve representative assessment of the environmental impacts of a system, and failure to take spatial variation into account may give misleading results
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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 want to know whether it is possible to go for modeling work to assess the eutrophication of a freshwater body without going for sample collection? If so, what kind of models can be run, and what kind of secondary data will be used to assess the eutrophication of a freshwater body?
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For eutrophication assessment of lacks, the data required are water clarity, nitrogen, phosphours and chlorophyll.
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It is said that a pond becomes eutrophic with higher values of N/P ratio. It starts to be covered with algal blooms, checks light penetration causing the death of the organisms inside. I wanted to know what is the range of value of N/P ratio exactly to be the water body eutrophic?
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Dear Hom Pathak
Firstly, it is important to note that the range is very wide and it depends on many other factors. One of the method I prefer to use to estimate the ratio for certain algae is by converting the ratio of atomic compositions and later convert it into mass. For example, green microalgae have the atomic composition of 10:1 to 20:1, we can convert it to become mas ratio and obtain ratio of 4.5:1 to 9.5:1 (Chiaudani & Vighi, 1974).
for further materials,you can refer to these articles
said that the lower N:P the more eutrophic level
less than 1: 1 to 6 : 1
high ratio (above 30) still supported the occurrence of eutrophication
Hope this one helps you
Good luck
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What are the harmful effects of eutrophication on the aquatic ecosystem ?
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Fish kill, oxygen depletion, little sunlight which reduces the activities of phytoplantons thereby affecting the entire ecosystem.
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There are numerous of different trophic classes, e.g. 3 oligotrophic, mesotrophic or eutrophic. However, you can even find more defined classifications using a smaller resolution. However, if I am searching for how these classes were quantified I can not find a multiple repeated studies quantifying these classes showing similar results. What is often quantified is a regime shift, clear lakes to turbid lake. If we could regarded this as biological recognized classes then we would have two trophic classes: oligotrophic and eutrophic (and perhaps some gray area). I understand that it is perhaps easier to talk in this way about an ecosystem, but It can also create issues if species then start to be classified as having preferences for certain trophic states. Is someone aware of any studies trying to quantify trophic states based on responses of biota (algae, macrophytes, fish, macro-invertebrates, zooplankton, etc)?
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J. C. Tarafdar, how does the (plus minus)10% comes in? The loss of energy/biomass to the next trophic state? For example starting at 100 - 10 - 1 - 0.1 - 0.01. But, why is 3-4 than the maximum? Make sure that you do not mistake the trophic level in a food web/chain with the trophic state of an ecosystem, of which I am speaking of.
I added a figure to what I would expect to find in literature. I would expect to find something representing the red line which show changes along an increase of an univariate/multivariate gradient. The trophic levels are here expressed as the total biomass/energy in a system since, we can observe a regime shift from a clear lake full of plants to a turbid phytoplankton dominated lake. However, this does not mean the amount of biomass/energy in that system changed. I have the idea it represents a gradient like presented with the green line, where we just create classes based on more subjective observable patterns.
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I am an undergraduate. My research is to find solution for control algal bloom
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Yes, you think correctly. The percentage of organics will increase
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I am doing a research of monitoring algal blooms in inland water bodies
How can i extract the pixel values of Chlorophyll a and Total Suspended Matter from the processed C2RCC images in SNAP. I have attached geotiff images of the two parameters.
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Hello,
It is better if you keep the files has netcdf. Using Snap, you can use the "pin" function, you could add a pin randomly to your map on SNAP, then you open the "pin manager" in the menu and you will see that you could add Lat and Lon in the first columns. You just have to export the extraction in a CSV file (located on the left of the "pin manager" window. ALternatively, you can create your own csv file with the lat and long information and upload them in SNAP, here is a youtbue video with more information: https://www.youtube.com/watch?v=5znAQH6vrLs
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A lake is full of a layer of algae and even with mechanical means it cannot be removed. What can be done to remove it completely . Please suggest the remedial measures. The measure can be  Physico-chemical or biological methods.
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I think the best method is the use of natural floating andby floating treatment wetlands system / constructed floating plants that can have all of the nutrients and not only can control the light and alga but also can remove all pollutions floatingand that is environmentally friendly and easy to apply in most of the reservoirs.
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Usually surface fresh water bodies have nitrate concentration <1 ppm.
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Well,
The percentage of nutrients from phosphorus in lakes is the lowest percentage needed for the plant. The ratio of nitrogen to phosphorus in plant tissue ranges from (10: 1) to (15: 1).
  If the ratio of N: P in the water is greater than (15: 1) then the lake is limited to phosphorous. Phosphorus will be consumed before nitrogen is used, so growth will be limited. Eutrophication in lakes can be controlled not only by nitrogen reduction but by phosphorous which will reduce the algae production rate, as the chlorophyll concentration increases with increasing phosphorus concentration.
Rank Condition
First; N:P ratio>15 Limited in P
Second; N:P ratio<10 Excess in P
Third ; N:P ratio:10-15 Saturated in P
Regards
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what the role of invasive plant allow with native if it has low population then native under submergence and eutrophication conditions? Does it will be out-compete native even in low population due to allelochemicals effects?
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Most probably due to increase of nutrients
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The presence, prevalence, occurrence frequency and parasitization frequency of different parasites of fishes vary depending on water quality status. Possibly water temperature, dissolved oxygen, BOD, COD influence the which, where, how much parasites prevail and parasitize fish host. Further fish health.is impacted by water quality. Degraded physicochemical regime adversely affect fish health and fish subject to multiple stressors are much more vulnerable to parasitic infestation. Insightful discussions are welcome to unveil the interactionbetween/among degraded water quality factors and parasites as well as between/among multiple stressor induced  ill health related  biological, haematological, immunological, biochemical parameters.  Also share your views about biochemical/stress markers can be counted as indicative to those interactions
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Parasites have been used as bioindicators for habitat types or areas, for years and for species hots using the indicator value methods , I have attached this files
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As in high rainfall zone having percolate soils how this problems intensify or whether there may be such situations arises of eutrophication.
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Sincere thanks resp.Dr. Ghosh and Dr. Mitra for valuable remarks
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(in answering, please indicate your country or location)
Some background information (arranged alphabetically- not ranked))
Carbon pollution/climate change (CO2) : (impacting both developing & developed countries- a threat to all most all social, economic and environmental sectors- biodiversity, ecosystems, water, agriculture, fisheries, infrastructure, public health, displacement/climate refugees, livelihoods);
Heavy metals (HM) pollution (As, Cd, Hg, Pb) : (> 50% of world soils are contaminated with heavy metals including As, a number of HM can cause cancer, they are persistent, bioaccumulative & toxic and also endocrine-disrupting, caused food and water contamination worldwide);
Nutrient pollution (N, P) (sourced from agriculture use of fertilisers, manure and sewage treatment plants, causing eutrophication (algal blooms) and hypoxia (low dissolved oxygen< 2.8 mg/L) worldwide and killing aquatic biodiversity including fish, bottom-dwelling animals, and ecosystem collapse);
Oil pollution: The oil spill is an environmental disaster; crude oils are mixtures of hydrocarbon compounds including BTEX, and PAH, some of which are toxic and can cause cancer (benzene and some PAHs). Lighter oil can be taken up by fish and plankton. Heavier oils would coat surfaces (birds) and cause long-term damage to ecosystems. Oil can be accumulated in the food chain (algae-zooplankton-invertebrates-fish-birds-humans). Seagrasses, plankton, mangroves and corals are very sensitive to oil;
Pesticides pollution (glyphosate, endosulfan): Pesticides are persistent; bioaccumulative & toxic, and some are carcinogenic endocrine-disrupting; pesticides can cause surface and groundwater and food contamination, may kill pollinators (bees), fish, tadpoles, poison birds and can cause cancer, infertility, male sterility in humans; pesticide residues can enter into the environment via spray drift, surface runoff, drainage discharge, soil dusts etc;
Plastic pollution (microplastics<5 mm; macroplastics>200mm) : (a threat to all nations, 60-80% marine litter; plastic particles are hydrophobic in nature and can adsorb high risk organic & inorganic contaminants; large plastic items can cause entanglement or injury or killing of birds, mammals, turtles, whales, dolphins, seals and fish, much smaller micro-plastic particles (microbeads) white in colour, mistaken by surface feeding fishes as food);
PM (Particulate matter): PM are microscopic solid or liquid matter suspended in the atmosphere of Earth. Inhalable coarse particles are between 2.5 (PM2.5) and 10 (PM10) micrometres (μm). Particulates are one of the deadliest forms of air pollution. Due to their ability to penetrate deep into the lungs and bloodstreams unfiltered, PM can cause permanent DNA mutations, heart attacks, respiratory disease, cancer and premature death. The burning of fossil fuels and stubble burning generate significant amounts of particulates.
Sewage pollution: Sewage water when drained off into rivers without treatment can cause a chain of problems like spreading of diseases (cholera, diarrhoea), eutrophication, increase in Biological Oxygen Demand (BOD). Sewage is mainly observed in developing countries, however, during extreme events (floods) overflowing of sewage systems can lead to sewage pollution in both developed and developing countries.
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All pollutants are dangerous in environment.
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I want to calculate the eutrophication impact, I have the amount of fertilizer but does it depends on the crop, or the type of soil, or both?
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This research shows the effect of soil type on nutrient loss
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I am trying to amplify DNA with 16S and 18S primers. DNA is extracted from water samples collected from the blooms. None of the samples had bands. I tried with Accupol taq polymerase and KAPA readymix, still, I can not yield any results. Has anyone encountered the same problem? What can you recommend?
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I have not tested the primers with any other samples from the blooms before. I am amplifying DNA from an estuary and it worked in areas where there were no blooms. I have not changed the commercial kit yet, thank you for that, I was thinking, may be there could be something else other than changing commercial kit.
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Hi, I'm in the process of doing algal cell counts using an utermohl chamber and a inverted microscope at 640x magnification.
The samples were taken mid-July from an estuary (considered eutrophic) that flows into Lake Erie, and were treated with Lugol's Iodine and then diluted with Phosphate Buffered Saline. The samples are allowed to acclimate to room temp and gently shaken before they are diluted and added to the settling chamber.
There is one very common phytoplankton that shows up in nearly all my fields of view, so I would like some other more experienced opinions on the identification of the algae in question (not necessarily the species, but at least the class). I keep going back and forth between Ulothrix (which apparently is less common in the summer) and either the Diatoms Melosira or Aulacoseira (which always appear more golden in photos online with just a few exceptions). I also think I have some Tribonema in my samples as well. I've also noticed what I thought might be an auxospore on some of the cells, but someone recently informed me that there are some parasitic algae that are known to infest diatoms. These cells are typically about 6 um wide and 10-12 um long. The reason that I suspected Ulothrix initially was the coloring of the chloroplast, but I'm noticing that my other diatoms also have this blue coloring (just the nature of light microscopes?). Here's an album that consist mostly of the unidentified filament (I'm thinking it's a diatom) and a couple photos of aulacoseira/melosira or tribonema.
One other fairly common observation is that of a small yellow 3-D starburst like colony with "knobby" ends. I would estimate the the entire colony is between 10-15 um (quite small!) compared to some of the diatom colonies I've seen. It also doesn't look quite like actinastrum due to the "knobs" on the ends (maybe also a trick of the scope).
One other thing I've seen are what I believe are dinoflagellates and possibly their resting cysts.
Here's some of the resources about the site and algal community:
and some resources I've used in an attempt to make an ID:
Thanks for all of your insight and advice!
-Amanda
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Maria Van Herk and Amanda Herzberg looks like the stellate organism is in fact a bacterial colony and not Snowella as i had mistakenly suggested, my apologies!!
Specifically these resemble Planctomyces bekefii.
see this link for clarification:
Thank you for clearing up this confusion i too have seen these in a number of samples and am glad to have an answer myself!
-Kyle
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I require information for my literature review. It would be of a great help if you can suggest me related reading materials concerning the agricultural practices, blooming of algae.
If you can provide me info on the role played by fertilisers on algal blooms it would be much helpful.
Thank you
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Abhishek Mukherjee and Weifei Yang thank you so much
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I heard 30-40% vegetation could be good for lake health but beyond 40% would result excess nutrient enrichment and turn lake eutrophic! Is there any relation that exists between aquatic vegetation spread/volume and trophic status of a lake?
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Dear Bayan,
This depends very much on the type of vegetation. For instance, floating macrophytes that are invasive (e.g. Eichhornia crassipes, Lemna spp.) grow on the surface, thus exerting a shadow effect on the water that limit other submerged plants and phytoplankton. When these macrophytes cover most of the lake's surface, they monopolize most resources (light, nutrients) and are favoured by massive nutrient inputs. However, submerged macrophytes do not cause (at least at the same level) this shallow effect, and then a competition for the available nutrients is established between the submerged macrophytes themselves and phytoplankton. Under extreme eutrophication, phytoplankton have advantages and can exclude most submerged macrophytes turning into a turbid phase, though some species are more effective than others under this competition,. This means that extreme eutrophication usually bring to the exclusion of submerged macrohytes either by phytoplankton or by floating macrophytes. Thus, the absence of submerged macrophytes is usually linked to high levels of eutrophication.
Concerning the percentage, I would not say that a certain percentage of coverage is mostly related to eutrophication, but instead the diversity of the submerged macrophytes' assemblages. As as general rule, which coincides for most communities, extreme levels are profited by a few species that monopolize most resources as being more effective in resource adcquisition or in resistance to the extreme conditions, thus the community is empoverished and diversity decreases. This is also true for eutrophication, with diversity of submerged macrophytes generally droping when eutrophication increases over a certain level, thus promoting the dominance of exclusion processes in the community.
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Most of devices are set for measurement in range of salinities from fresh to ocean. But in the world exist many lakes and other water bodies with extra-high salinity.
Who knows about the latest advances in device measurement of Dissolved Oxygen in highly saline waters and brines?
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Dear Peri, I plan to publish it as a book, guide or manual "Determination of nutrients. Application for higly saline waters". It would be great to complete this work by the next ISSLR conference in 2020.
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The levels of phosphorus (fecal coliform) and nitrogen in the lake are too high.
This level is due to the flow of Toxic and agricultural fertilizers and waste water from the villages of this area to the surface and groundwater of the area?
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Agricultural fertilizers are one of the main human causes of eutrophication. Fertilizers, used in farming to make soil more fertile, contain nitrogen and phosphorus. The use, or overuse, of fertilizers can cause these nutrients to runoff of the farmer's field and enter waterways. Eutrophication can have serious effects, like algal blooms that block light from getting into the water and harm the plants and animals that need it. If there's enough overgrowth of algae, it can prevent oxygen from getting into the water, making it hypoxic and creating a dead zone where no organisms can survive.
The following is a list of methods that can be used to control eutrophication:
planting vegetation along streambeds to slow erosion and absorb nutrients.
controlling application amount and timing of fertilizer.
controlling runoff from feedlots. The best, easiest, and most efficient way to prevent eutrophication is by preventing excess nutrients from reaching water bodies. This can be done in a number of ways, the simplest of which is just being aware of the chemicals and fertilizers that we are using.
Regards
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We have two SBE19plisV2 CTD we use on a weekly basis, both in small eutrophic estuaries where DO saturation range from 0 to 250%, and the costal hyper oligotrophic East Mediterranean sea, where DO fluctuations are miniscule.
We are using the SBE 43 for many years now and until recently, these instruments were extremely reliable. We are not sure what exactly was changed,  but in the ‏last two years, the reliability of the instruments dropped dramatically, to a degree that we are now considering to switch to a different manufacture or keep a backup instrument.
1. Did anyone else find out that the reliability of SBE43 sensors dropped recently?
2. Can anyone suggest alternative sonsors that are (as always):
a. Reliable
b. Accurate
c. Cheap
d. Can be mounted on a seabird CTD
Thanks for your help
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Ok, Yair, thanks. I understand. If you checked the electrolyte and the membrane, this case may have two sources of problems: 1) sensor breakage 2) problem with the main probe.
We didn't face such probem.
In my humble opinnion this problem can be solved just by service specialists of seabird company.
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In Southern Highland Zone (SHT) -Tanzania there different fertilizer brands used in paddy farming, the commonly used fertilizer in paddy farming are Nitrogenous fertilizer and Phosphatic fertilizer, these fertilizers are used for basal dressing during transplanting or sowing seeds and for top dressing during growing plants. The common used fertilizer included UREA, Calcium Ammonium Nitrate (CAN), Di Ammonium phosphate (DAP), Triple Super Phosphate (TSP) and other brands containing Nitrogen and Phosphate (Ngailo et al., 2016). In paddy farms fertilizer are applied by commonly broadcasting method where farmers just broadcast the fertilizer in the field. And after few days they flood the field with water (Amuri et al., n.d.). This fertilizer application practice and flooding practice has adverse effect since the applied fertilizer is likely to be lost by leaching and runoff resulting in poor plant response to the added fertilizer hence low yield return. Despite getting low yield due to poor fertilizer application practices, the leaching and lost fertilizer in water increase the plant nutrients to surface and ground water (Eutrophication) which increase the growth of algae blooms and other vegetation in water bodies such as dams, rivers and lakes resulting in decrease the amount of dissolved oxygen in water and decrease in water levels affecting the marine life, hydroelectric power (HEP) plants and other water users such as Human and animals (Sharpley & Mcdowell, 2016). In Tanzania currently, there is report in increased growth of algae blooms and other vegetation in lakes, rivers and dams receiving water from commercial paddy farms this signifies the increased concentration of P levels in water, hence affecting the marine life and the amount of water for HEP.
The best fertilizer application practices and fertilizer types used need to be reviewed to develop the mitigation measures and guiding policy for fertilizer users to reduce the risk associated with poor fertilizer use in paddy farms, the problem is very serious since many paddy farms are located in lowland where the water table is usually very shallow, exacerbating the processing of eutrophication, fertilizer which are less soluble and with granules which release the required nutrient slowly will be important to ensure fertilizer does not just be lost to water, also the fertilizer application practices which reduce the leaching of fertilizer are important such as banding application ensure the fertilizer is closer to the plant and can be absorbed immediately, also the practice of flooding the farms soon after fertilizer application has to be reviewed to ensure friendly use of fertilizer to the environment and other ecosystem
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It would be best to consult with soil scientists with experience in the fertilization of wetlands and how the hydric soil conditions can tie up phosphorus, making it unavailable. USFS soils researcher William McKee (now retired) did several studies in applying fertilizers to coastal forest soils with high water tables. Your subject sounds like one worthy of study, especially if combining the types and properties of paddy soils, high water tables, available and leaching of nutrients, and water quality effects from flooding and runoff. Paddy farming may have different issues to consider as compared to forest. McKee and others found that phosphorus was deficient for pine tree growth in soils with high water tables, and triple super phosphate added had benefit. Spodisols did not respond well to any combination of nitrogen and phosphorus fertilizers. Also noted was the rise in water table when trees were removed, making regeneration difficult in some cases. As the new forest stand used water (transpiration) and lowered the water table, the phosphorus became available and growth markedly increased in response. Due to the cost of fertilizers, it would be best to have soil scientist involvement to help determine nutrient deficiency, conditions of optimum timing for fertilization, fertilization rate, consideration of flooding practices, etc.
Your ideas suggest you are well on your way toward viable study and including the desire to help identify best management practices and advice for responsible paddy farming to help minimize adverse effects. If there are significant issues with fertilizer leaching identified In some areas, you might want to check for example effects of nitrate increases in vicinity groundwater, which can limit some potable water use if excessive. As indicated, runoff or other discharges of fertilizer can have severe effects to aquatic ecosystems.
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How to link ecology of coastal systems to address ocean deoxygenation
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Sewage disposal in oceans increases BOD and decreases DO
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It was demonstrated that there are seasonal changes of phosphate in the lakes, which was related to the eutrophication . In general, summer has higher level of phosphate whereas the winter has low phosphate. There are many reasons for such patterns. Recently, my work on the inorganic phosphatase from from iron oxides in the waters- contributed by the sediments might the the reasons. These inorganic phosphatase are sensitive to the temperature changes.
The details of my work can be found :
  • Hydrolysis of Phosphate Esters Catalyzed by Inorganic Iron Oxide Nanoparticles Acting as Biocatalysts, Astrobiology 18(3) DOI: 10.1089/ast.2016.1628
  • Hydrolysis of Glucose-6-phosphate in Aged, Acid-Forced Hydrolysed Nanomolar Inorganic Iron Solutions — An Inorganic Biocatalyst?2012, RSC Advances 2(1):199-208 DOI: 10.1039/C1RA00353D
In fact, it is a long history to use the iron salts to control the phosphate in the lakes. It was found that the effect was short , and the reasons for the short behaviors were considered as the decrease of iron sorption. Although some papers were demonstrate that the oxygen level, as well as the content of SO4 in the water might relate to the decrease of sorption capacity of iron in the sediment, but I think the main reasons were from these inorganic phosphatase, from the iron oxide nanoparticles in the water. The evidence of the total phosphorus and inorganic phosphate changes after the iron treatments in the lakes might be further indicate the contribution inorganic phosphatase . I would like to have more evidences to support my hypothesis ..Thanks
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This method is intended to determine the stable isotope content of the oxygen of the phosphate group in order to know the origin of the latter. (P in the environment can be organic and inorganic phosphates) .. the objective is not the dosage of the concentration of phosphoric acid. it is not a classic and traditional method for orthophosphate by spectrophotometry
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Hi everyone,
I am trying to assess the environmental footprint of an industrial-scale plant for high-lipid microalgae cultivation. Currently, I am focussing on waste water from the cultivation plant. I wonder if water left after the algae harvest can be led back into the sea without further treatment. Some thoughts/open questions:
- N and P concentration should be low at the end of the lipid-production phase (starving conditions), so eutrophication risk should be low. But: Is N and P concentration low enough? How much is acceptable?
- Could high NaCl concentrations in the cultivation medium be potentially harmful to sea life?
- Could algae left in the waste water pose a risk, e.g. could they set foot in the sea and cause an artificial algal bloom?
I'm thankful about your thoughts/experiences and even more thankful for studies / laws / regulations on the topic.
Best regards.
Benjamin Portner
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Dear Benjamin
I think Yes.
Industrial and large-scale production of biofuels from algae may cause water pollution.
Biofuels can be produced from micro-algae grown in ponds or tubes on land. This requires considerable fertilizer inputs that may pollute the environment if not treated properly. To ensure sustainable production of biodiesel from micro-algae, it is important to develop cultivation systems with low nutrient losses to the environment.
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Eutrophication remains one of the foremost environmental issues threatening the quality of lake surface waters yet comparatively little is known of the process of algae decomposition. Thus, which method is suitable to characterize the degree of algae decomposition? The mass quality? Chlorophyll a? Dissolved organic matter? 14C labeled stable isotopes? Can anyone give some suggestions? Thank you for your attention.
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Dr. Lei: I had recently come across a few studies which address an aspect of this issue related to treatment of drinking water affected by AOM. It would seem that the methods for measuring AOM would be similar in both cases even though the outcome issue/concern is different. These studies suggest several different measurements that comprise the characteristics of AOM. I had saved the abstracts from only two of these studies, see below.
Henderson, Rita K., Andy Baker, Simon A. Parsons, and Bruce Jefferson. "Characterisation of algogenic organic matter extracted from cyanobacteria, green algae and diatoms." Water research 42, no. 13 (2008): 3435-3445. Abstract: Algogenic organic matter (AOM) can interfere with drinking water treatment processes and comprehensive characterisation of AOM will be informative with respect to treatability. This paper characterises the AOM originating from four algae species (Chlorella vulgaris, Microcystis aeruginosa, Asterionella formosa and Melosira sp.) using techniques including dissolved organic carbon (DOC), specific UV absorbance (SUVA), zeta potential, charge density, hydrophobicity, protein and carbohydrate content, molecular weight and fluorescence. All AOM was predominantly hydrophilic with a low SUVA. AOM had negative zeta potential values in the range pH 2–10. The stationary phase charge density of AOM from C. vulgaris was greatest at 3.2 meq g−1 while that of M. aeruginosa and Melosira sp. was negligible. Lower charge density was related to higher hydrophobicity, while it was related in turn to increasing proteins >500 kDa:carbohydrate ratio. This demonstrates that AOM is of a very different character to natural organic matter (NOM).
Villacorte, L. O., Ekowati, Y., Neu, T. R., Kleijn, J. M., Winters, H., Amy, G., ... & Kennedy, M. D. (2015). Characterisation of algal organic matter produced by bloom-forming marine and freshwater algae. water research, 73, 216-230. Abstract: Algal blooms can seriously affect the operation of water treatment processes including low pressure (micro- and ultra-filtration) and high pressure (nanofiltration and reverse osmosis) membranes mainly due to accumulation of algal-derived organic matter (AOM). In this study, the different components of AOM extracted from three common species of bloom-forming algae (Alexandrium tamarense, Chaetoceros affinis and Microcystis sp.) were characterised employing various analytical techniques, such as liquid chromatography – organic carbon detection, fluorescence spectroscopy, fourier transform infrared spectroscopy, alcian blue staining and lectin staining coupled with laser scanning microscopy to indentify its composition and force measurement using atomic force microscopy to measure its stickiness. Batch culture monitoring of the three algal species illustrated varying characteristics in terms of growth pattern, cell concentration and AOM release. The AOM produced by the three algal species comprised mainly biopolymers (e.g., polysaccharides and proteins) but some refractory compounds (e.g., humic-like substances) and other low molecular weight acid and neutral compounds were also found. Biopolymers containing fucose and sulphated functional groups were found in all AOM samples while the presence of other functional groups varied between different species. A large majority (>80%) of the acidic polysaccharide components (in terms of transparent exopolymer particles) were found in the colloidal size range (<0.4 μm). The relative stickiness of AOM substantially varied between algal species and that the cohesion between AOM-coated surfaces was much stronger than the adhesion of AOM on AOM-free surfaces. Overall, the composition as well as the physico-chemical characteristics (e.g., stickiness) of AOM will likely dictate the severity of fouling in membrane systems during algal blooms.
Zhang, X., Fan, L., & Roddick, F. A. (2013). Influence of the characteristics of soluble algal organic matter released from Microcystis aeruginosa on the fouling of a ceramic microfiltration membrane. Journal of membrane science, 425, 23-29.
Her, Namguk, Gary Amy, Hyoung-Ryun Park, and Myoungsuk Song. "Characterizing algogenic organic matter (AOM) and evaluating associated NF membrane fouling." Water research 38, no. 6 (2004): 1427-1438.
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In a lake full of cyanobacteria blooms, Nitrogen and Phosphorus levels are often really high. We're actually on a project, and we'd like to find some ways to eradicate or just reduce the process of eutrophication in the lake. We include many methods such as using home-made floating islands on which some plants enter in competition with cyanobacteria, but 1) we're looking for solid and durable matter that can survive erosion and all seasons. 2) And we prioritize the species consuming more nitrogen and phosphorus. 3) We also look at the possibility of using some bacteria spreading in the lake to compete with cyanobacteria. All advice and articles are welcome!
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Hans Matthijs (J.C.P.Matthijs@uva.nl) used hydrogen peroxide to clean lake waters from growth, with great success. He even got the goverment permission to do it. The procedure is very efficient and save for all usefull species. I do not know was it patented or not.
He, to the deep regret of many of his colleagues, has passed away, but maybe there is somebody who proceeds.
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I want to understand the relationship between the two chemical parameters
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All the above are correct. Higher TDS (as salinity) decreases the dissolvability of oxygen and so has less oxygen due to physics. However, the major driving force for very low dissolved oxygen is usually due to high bloom conditions in the surface waters. In partially mixed and highly stratified -salt wedge areas of estuaries , the water column is separated by the water density physics. This leads to lower layers being more saline (higher TDS) and cut off from surface oxygen. If an area has high nutrients, the phytoplankton bloom , die, sink , and decay in the bottom waters, using up the oxygen. And so for many situations in estuaries, the higher salinity waters, especially at the lower salinity areas of estuaries ("top" of the estuarine area) with high nutrients, eutrophic conditions, and stratification can have much lower DO , reaching hypoxic or even anoxic (no DO) levels in the bottom waters. The area of an estuary closer to the ocean will have higher salinity throughout the water column and high dissolved oxygen unless a very large bloom offshore has occurred.
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Dear professors and researchers
This photo was taken recently in the middle of Mosul city along Tigris river pathway. what is the causes of this extinsive growth! And what can we do for the river to back it healthy! It’s worth to mention Tigris river the only sourse of raw water for water purification planets, and in this photos the uptake of the planet is very close!
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Dear Dr. Fadhel,
I'll try to answer it in a nutshell as follows:
1. Presence of Higher dissolved inorganics viz. nitrates, phosphates and silicates (primarily for diatoms) and carbon through natural advection or upwelling and/or anthropogenic influences (sewage, irrigation). Intertidal injection also introduces copious amount of nutrients. In the freshwater regime dissolved orthophosphates serve as the limiting nutrients for bloom while in marine environments it is generally dissolved nitrates that limit the algal growth. In estuarine set up however, both can play significant roles depending on the section of the estuary and the species concerned.
2. A rise in temperature, dearth of dissolved oxygen, rapid fluctuation in pH-resulting in the absence of higher trophic level consumers, zooplankton to fish, leading to unchecked phytoplankton bloom.
3. Present of condition amicable for all organisms, especially spring bloom, after a phase of tiding over adverse conditions may also lead to explosion in numbers of microalgae.
4. Absence of competitive macrophages in the waterways, leading to monopolization by the phytoplankters in exploitation of the available resources.
5. Ability of certain species under some genera to withstand or adapt to adverse conditions and resultantly out-competing other in terms of dominance.
6. Natural catastrophes such as flood through excess release from dams, torrential downpour, flood, cyclones etc can and does introduce land wash or churned sediment bed-released nutrients into the water column that might and do favour microalgae.
7. Introduction of nuisance species/non-native species through ballast discharges which might find the ambient conditions ripe for the picking and may end up becoming the dominant species causing multiple blooms year round. Best example:: Odontella in Bay of Bengal.
8. Seawater incursions into the aquifer or the rupturing/fissuring of bedrock resulting in admixing of waters with higher nutrient load and ultimately causing enrichment of the surrounding water bodies. Sedimentary rocks with higher nutrients can and do leach huge quantities of inorganic load into the water.
9. Presence of certain microbes trigger the enrichment of certain nutrients, such as phosphate solubilizing bacteria help to release phosphates from apatite minerals through synthesis of low molecular weight organic acids etc, can lead to eutrophication and exploitation by certain algal communities causing blooms.
There are various other more beautifully intricately woven factors responsible for eutrophication and to keep it simple the aforementioned points should suffice.
I hope this helps you,
Regards,
Dr. Abhishek Mukherjee
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My hypothesis is:
1. More nutrients (from land fertilization) means more primary productivity which removeds CO2.
2. Warmer seawater means less oxygen sollubility, therefore less Oxygen in the deep water (Breitburg et. Al. below) which means less organic matter is Oxydized and more CO2 is buried in sediment
Did anyone try to quantify these effects?
1. Breitburg, D.; Levin, L. A.; Oschlies, A.; Grégoire, M.; Chavez, F. P.; Conley, D. J.; Garçon, V.; Gilbert, D.; Gutiérrez, D.; Isensee, K.; Jacinto, G. S.; Limburg, K. E.; Montes, I.; Naqvi, S. W. A.; Pitcher, G. C.; Rabalais, N. N.; Roman, M. R.; Rose, K. A.; Seibel, B. A.; Telszewski, M.; Yasuhara, M.; Zhang, J. Declining oxygen in the global ocean and coastal waters. Science (80-. ). 2018, 359.
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It should be other way , effect of climate change on eutrophication.... Recent research suggests that climate change will reinforce the negative consequences of man-made eutrophication and make it more difficult to improve water quality in lakes and estuaries . The direct effects of nutrients are thus also tangled with the structure of food webs, and in turn the nature of food webs is influenced by climate. Some interesting PDFs enclosed..
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The lake is c.6.3 hectares and <1m deep. The lake has slightly elevated TP and TN concentrations and there is a concern that removing the invasive water soldier could cause a phase shift from a clear macrophyte dominated state to one that is turbid and phytoplankton dominated. Any comments or experiences about how to approach the issue are welcome. Also how realistic is it to fully remove water soldier so that it does not return?
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It has been a while, but I thought I would provide an update about management actions undertaken to help control the water soldier situation on the lake of concern. A phased removal of the water soldier using Truxor machines began in October 2016 and happened again in September 2017. In September 2017 a boom was also inserted to prevent its spread back in to the removed area. It was our intention to have the boom in from the start of the first removal phase, but limited funds unfortunately prevented this. In total c.20-25% of WS has been removed. Monthly monitoring has been taking place to inform chemical and biological responses, with the boom allowing differences to be observed between open water areas versus those dominated by WS. It would also allow us to observe whether any desirable submerged macrophyte species, which used to dominate / be present, will re-establish. We will continue to monitor the situation and assess the changes in the lake prior to deciding whether further WS should be removed again later this year. I have attached some photos showing the inserted boom (0991 & 0992 are September 2017 and 1019 October 2017). The red buoys are some of the monitoring points.
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Eutrophication is defined as the nutrient enrichment of an aquatic ecosystem. This factor favors the proliferation of organisms that consume the nutrients and oxygen.
my question is:
Is it possible to relate these events to climate change? obviating the contribution of direct nutrients by human action.
thank you
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Dear, have look at very interesting attached PDF.
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Reduction of eutrophication in agricultural discharge .
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Phosphorus, like nitrogen, is an essential element needed for crop growth. It is a basic building block for compounds that store and transfer energy, nucleic acids, and other organic compounds. Unlike nitrogen, phosphorus is not found in a gaseous form, and so the cycle does not have an atmospheric component. It is most commonly found in rock formations and sediments as phosphate salts. It is also found as part of the organic material in soil. Weathering processes dissolve the phosphates, and plants uptake phosphorus from the soil water in the form of hydrated phosphate ions—soluble phosphorus. Phosphorus is released back to the soil as crop residue decomposes, and the cycle repeats. Phosphates are not very water-soluble, and quantities of soluble phosphorus in soil are generally small, ranging from 0.2 to 0.3 milligrams per liter. Farmers apply commercial phosphorus fertilizers to supplement the usually low quantities available in the soil. Over-application can lead to the buildup of phosphorus in the soil. As the phosphorus levels build up in the soil, the potential for phosphorus in a soluble form increases (Sharpley et al. 1999). Dissolved phosphorus that is transported from farm fields to lakes, rivers, and streams can lead to excessive aquatic plant growth, resulting in eutrophication. Phosphorus is sometimes the limiting factor for biomass production in freshwater ecosystems; even small amounts (concentrations as low as 0.02 mg/L) added to the system can produce significant increases in plant and algal growth (Sharpley et al. 1999). Generally, the factors that cause phosphorus movement are similar as those that cause nitrogen movement. Transport mechanisms are erosion, surface water runoff from rainfall and irrigation, and leaching. Factors that influence the source and amount of phosphorus available to be transported are soil properties, and the rate, form, timing, and method of phosphorus applied. The phosphate ion attaches strongly to soil particles and makes up a part of soil organic particles. Any erosion of these particles will transport phosphorus from the site. Phosphorus can also be transported as soluble material in runoff and leaching water. When water moves over the soil surface, as it does in runoff events, or passes through the soil profile during leaching, soluble phosphorus will be transported with the water. Applying phosphorus fertilizer or manures on the soil surface will subject them to both runoff and erosion, particularly if the application takes place just before a rainfall, irrigation, or wind event that can carry the phosphorus material off site. If, however, the fertilizer or manure material is incorporated into the soil profile, it becomes protected from the transport mechanisms of wind and water. Leaching of phosphorus is at a higher risk through coarse textured soils or organic soils that have low clay content. Phosphorus is primarily lost from farm fields through three processes: attached to the sediment that erodes from the field, dissolved in the surface water runoff, or dissolved in leachate and carried through the soil profile. On cultivated fields, most is lost through erosion, whereas on non-tilled fields most phosphorus losses are dissolved in surface water runoff or in leachate. Cultivated acres with phosphorus-rich soils, however, can also lose significant amounts of phosphorus dissolved in the runoff or the leachate. EPIC simulates the phosphorus cycle as shown in figure 26. EPIC simulates mineral and organic fractions of soil phosphorus. The mineral fraction consists of available (soluble), active (loosely labile), and stable (fixed) pools. Only phosphorus compounds that are soluble in water are available for plants to use. The soluble and active pools are assumed to be in rapid equilibrium (several days or weeks). The soluble pool is input and the size of the active and stable pools relative to the soluble pool is set by EPIC based on the amount of past soil weathering. The active pool is in slow equilibrium with the stable pool. Fertilizer phosphorus is assumed to be in soluble form which is mixed uniformly to a specific depth. Thus, fertilizer phosphorus contributes directly to the soluble pool. Organic phosphorus is divided into the fresh residue pool, consisting of phosphorus in the microbial biomass, manures, and crop residues, and the active and stable humus pools. Humic mineralization occurs in the active pool only. The model accounts for transformations between pools within each fraction and also between the organic and mineral fractions. Plant use of phosphorus is estimated using the supply and demand approach, which balances soluble phosphorus in the soil with an ideal phosphorus concentration in the plant for a given day. Phosphorus in the surface layer is partitioned into adsorbed and solution phases using a constant partition coefficient similar to the method described by Leonard and Wauchope (1980). Adsorbed phosphorus attaches to soil particles in the soil matrix, thereby removing the material from solution. Sediment transport of phosphorus is simulated with a loading function similar to that used for organic nitrogen transport. The amount of soluble phosphorus removed in surface water runoff is predicted using soluble phosphorus concentration in the top 10 millimeters of soil, runoff volume, and partition coefficient. A similar method is used to predict soluble phosphorus lost with percolation water as leachate. Part of the phosphorus is removed from the field with the harvested crop and remaining crop residue is added into the organic pools where it is available for mineralization. Transformations of organic phosphorus in crop residues and soil organic matter are similar to the transformations of crop residues, soil organic matter, and organic nitrogen in the PAPRAN model (Seligman and Keulen 1981). Over years of farming, cropland soils tend to either gain or lose phosphorus. In cases where soils experience net losses (mining), reductions in soil quality, soil productivity, and crop yields can be expected to follow. Mined soils can be restored through conservation management practices that increase soil organic material and eventually re-establish a balanced phosphorus cycle.
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As it is mentioned in the title. Is anybody know low cost electrical or "light" method to do continious basic measurements in artificial reef tank? I'm thinking about no- chemical method, where the probe can be settled in the tank.
Thanks for all answers
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I prefer to use a commercial test kit if 50 cent/test is considered cheap.
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One of my student is doing her research work on eutrophication model of a lake ecosystem; since most of the modelling software are made for the system with tributaries; can anyone help me in find out the modelling tool for the assessment of eutrophication level without having any tributaries.
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As Ian said, you can assume that the nutrient and organic matter supply by point tributaries being equal to 0. However I suggest that you carefully consider all the rest of possible sources, which include, for instance, diffused runoff, atmospheric deposition, external animals dropping, internal load, etc
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One of my student is going to start her work on eutrophication modelling and sag curve modelling for a local pond extensively used for drinking purpose. Could anyone help me to find out the software's and manuals to proceed the work in a good way.
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Dear Dr. Kani,
you can collect water samples from local pond and measuring the chlorophyll a content and determining the trophic level of that pond during different seasons. Also, assessing some physicochemical parameters to evaluate the water quality status. You may identify phytoplankton if there toxic species or detect the level of Microcystis in water samples.
comparing your data with pervious study on the same pond, if there. Detecting human activities near to the pond that may help you to interpret your final data.
Use canonical corresponds analysis (CCA) to get the correlation between all different detected data.
Good luck,
Sara Sayed
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Is there a relationship between climate change and the accumulation of pollutant such as heavy metals in the marine environment?
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Yes in some cases Climate change can influence heavy metal concentrations, and therefore (bio) accumulation in the environment. A change of climate, such as reduced rainfalls can affects the concentration of heavy metals in water bodies such as dams. Basically the less water you have in a dam to dilute the pollutants the higher the concentration! Increasing temperatures also increase evaporation rates of rivers and dams, leading to increased concentrations of pollutants that are dissolved in the water bodies. Some phenomena such as "lake turn over" which is basically the mixing of water in a water body due to convectional currents are highly seasonal. Lake turnover is mixes water bottom and top layers of a water body and therefore increases the suspension or solubility of sediment bound metals. This exposes aquatic organisms to to higher levels of metals (metals are safer stuck in sediment that when in water).
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I've recently (May, 2017) found moderate levels of Cladophora, Oscillatoria, and Lyngbia in a 2nd order, softwater, coldwater stream in northwestern New Jersey (USA). A concern has been expressed that presence of these algae may be evidence that nutrient polluted seepage from a septic system is entering the stream. I'm not so sure. I know that high biomass of Cladophora in the Great Lakes has been considered an indicator of nutrient pollution, and cyanobacteria are also often considered indicators of nutrient pollution. But I suspect that low to moderate levels of these algae occur naturally without any pollution, but I'm not sure.
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Anila,
Thanks for your response. Unfortunately no one else has responded, so no expert answers. Maybe if I ask a slightly different question, or rephrase this one, I'll get more response and some answers. But I'm not sure what to ask yet.
Richard
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Hi all,
I am wondering what journals are good to target for publishing my paper which assesses a new technology for phosphate recovery. I have a couple in mind, I was just wondering if anyone else involved in this area has some suggestions.
Thanks!
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Thanks for your input everyone!
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One of the most famous lakes in indonesia, Lake toba got contaminated due to fishing nets. you can check the general situation through following link : https://www.pressreader.com/indonesia/the-jakarta-post/20170114/281681139571068
I have been looking for how to restore this kind of contaminated lake but I couldn't find any other case with the similar problem. Many cases are caused by pollution that reducing fishery productivity, however, in lake toba case, fishery is the problem. Does anyone of you have idea about restoration of this lake?
It seems that organic pollutant came into the lake water that causing leech and louse booming..
Thanks..
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    Usually these kinds of nets are called Ghost nets, since they drift around. They are also a problem to the open sea.
     As mentioned in the article you shared the fish dies eventually after struggling to set free from the net. As per my understanding- the more organisms die, the more BOD increases, which in turn causes anoxic conditions which kills more fish and cycle repeats. Lakes are a closed body of water where the impact will be higher and faster.
    The primary way to tackle this will be to physically remove these nets and  secondarily to implement laws  and awareness.I have found an article by FAO which states some mitigation methods, which might help you.
All the best!
Hope to visit the lake some day, hope it retains it's pristinely I saw via google images.
Regards,
Purva 
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It is a bloom from coastal waters
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Lathika:
Kindly provide scale and better focused pictures.
Best
Syed
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I want to have some reference materials regarding the physico chemical parameters ( pH, salinity, conductivity, depth , nitrate , phosphate , DO, BOD , chlorophyll a concentrations, , COD, sediment carbon, sediment pH, sediment conductivity, texture) and environmental conditions preferred by several species given in word document.If you have some information that will be much helpful.
Thank you.
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please see the information that provided by DR. Ton
thanks for sharing this Atlas.
regards
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I would like to perform anoxic incubation in mesocosm.
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The chemical and physical methods for dissolved oxygen removal are the following.
Nitrogen purging
Using hydrogen peroxide
Boiling at I atm for 30 min in open air
Boiling under reduced pressure
Sonication under reduced pressure
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What are the likely chemical changes in a soil as it becomes increasingly anaerobic ?
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Thanku Dr. Clinton  Rissmann.
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Goldfish can derive considerable energy through anaerobic metabolism and can survive for days under hypoxic conditions. But this anaerobic capacity as known is very high in another carp, Crucian carp, which has been reported to live for long periods under  anoxic conditions during winter. Rasbora daniconius, a minor carp, is said to have  capacity to live under anoxic conditions.
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Differences in  the anaerobic metabolism of 🐟 fish " are discussed " points of view , degree of temperature , PH. Levels of aquatic environmental condition  and individual adaptation to exposing conditions 
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Could you tell me what your opinion is about the effectiveness of best management practices (BMPs) to minimize agricultural phosphorus and nitrogen impacts on surface water quality? Do the BMPs really reduce nitrogen and phosphorus pollution in agricultural catchments? Can you suggest some research papers for me – especially about the lack of positive influence/lack of real management actions/most common barriers.
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BMPs are generally specifically designed to address non-point source pollutants to streams and other water bodies.  The term may have been adapted to other best practices or management measures to achieve some thing else.  Many BMPs for water quality help to reduce the direct discharges of pollutants, and could be applied whether point or non-point soiurces of pollution.  For nitrogen and phosphorus, BMPs are used in stream buffers to filter out P as it adheres to soil particles, and retained on site to be absorbed by trees or vegetation.  For nitrogen, which is more mobile, the absorbtion of water in the stream buffer raises the water table and soil wetness, encouraging denitrification, but also true that there may be some elevation of nitrogen in groundwater.  The longer the nitrogen is retained on the land or in the groundwater, the greater opportunity to denitrify or be absorbed by plants. The carrot to many is preferred over the stick, but you may need stick if the carrot does not work.  The problem is often the effects of activities that produce nitrogen or phosphorus are not on-site or near the discharge points, but downstream to other connected streams, waterbodies and aquatic ecosystems.  
BMPs are not a panacea, can be imperfect and will not address all the issues.  But if they are not designed, implemented, monitored and validated to be somewhat effective in most circumstances, then they are not really BMPs.  
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Despite many attempt of researchers I think that, at least in The Netherlands in eutrophic systems, there are no species of aquatic invertebrates correlated with any chemical component within the watersystem. The occurance of a species is mainly linked to the presence of a species specific substrate like stones, waterweeds, wood and in the smaller species like mites and oligochaetes also with the hydrological conditions. In Insects in which the adults mate in the surrounding terrestrial habitats (Ephemeropta, Trichoptera) the landscape is also of importance. Have there been any research or is there any paper in which a species is directly linked to a chemical compound within a natural (eutrophic) environment? That means no statistical stuff for I have seen that too many. Almost every species has a very wide range of occurrance for e.g. P, N, S etc. but no species has a narrow range. I ask you this, for communities differ in many ditches but chemistry is almost the same
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In my experience, community predictability decreases as nutrient concentrations increase, so I would expect somewhat random communities in eutrophic systems. These random patterns may mask signals associated with chemicals. It is also possible that communities in ditches are being constantly reset and that they are in various stages of redevelopment. I think your observations are consistent with meta-community ideas.
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I will be going for a fieldwork soon and would really need some help in this.
I would have to assess the eutrophication potential of the different sample sites and the formula i will be using is 
EP= Σi (mi x EPi)
where
•      EP=eutrophication potential in kg N-eq (alternate units also used such as kg P-eq)
•      mi = mass (in kg) of inventory flow i,
•      EPi = kg of nitrogen with the same eutrophication potential as one kg of inventory flow ‘i‘
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If you have excellent GIS files for watershed, an inventory of areas with agricultural use, cattle or animals, density of home septic systems, may help some in designing a sampling scheme.  Stream or river sections of low gradient, shallow, open to sunlight also tend to have more potential to develop algal blooms.  If you know aquatic insects, nutrified water with excessive algae development are apt to have low early morning DO and aquatic insects are more apt to be tolerant types.  So you might use indicators as these to adjust sampling system that address land use relative with potential nutrient increases  and riparian condition relative to stream shade and stream temperature.  Just to be clear, much agricultural nonpoint pollution sources are likely to be connected to stormwater runoff events.  Some nitrogen forms may increase with flow, others may decrease, and some scatter may exist.  If there are lakes/ponds or sloughs that capure flow, their nutrient levels and eutrophication status may be indicative.  Agricultural customs and practices including timing may also influence results.  If you can compare tributaries of similar size or stream order with various land use intensity (undesturbed forest to heavily disturbed or managed agriculture or high density animals), it may help define the relationship of land uses and activities to water quality.  
Since both streamflow and nutrient concentrations will vary with time and conditions, I would make sure I collect information on site conditions, algal presence, aquatic insects, photos showing stream condition, clarity, openness to sunlighr, channel form, GPS point.    I have never sampled for concentration of algae, but that may be indicative. 
The subject is complex, but you may find some experimental watersheds with results on nutrient flux and water quality variances with flow and land use.  My 1975 thesis in researchgate is dated, but it addressed the flow and nutrient changes on small forested catchments in Missouri, USA.  It may give you some ideas on how your study might improve or some old references I used.
To get mass kg during sampling time, you are going to need nutrient concentration mg/l times streamflow rate in cubic m/sec.  With some unit conversions, you can get kg/sec at time of sampling.  Both concentration and flow rate will vary with storms, so an estimate of annual nutrient loading takes much work for quantification, and that is why I suggested including indicators in field sampling unless you were well funded and much time to instrument or resample locations.
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Problems include lack of disturbance, succession, collapse of rabbit populations, eutrophication etc. Also interested in lichens. We hope to test some options.
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Depending  how rare these plants are you may also  consider having a collection of plants that represents the genetic diversity of the species  in safe secure environment  such as an in vitro collection in a lab or seed collection in a genebank. This will ensure survival of the species should any natural disasters, pest incursions, disease outbreaks occur. 
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Hello.
I made some research and found that there are some parameters as nitrogen, chlorophyl, phosphor and oxygen. But there are also others, that I can't fully explain. Its because almost of data are about the billabong (e.g. basins) which is not the same. I apologize for my english. You can answer in Czech language too.
Thanks.
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You already have two great responses.  Eutrophication of flowing streams is generally not a major concern within the national forest areas where most of my experience has been over my career.  Of course there may be temporary conditions of eutrophication and accumulation of organics of wetlands and non-flowing waters at times.  Conditions brought on by drought or extreme events.  One factor I would suggest is sunlight, streams or flowing waters, when open to sunlight as well as the nutrients and other factors suggested are much more apt to have dense plant growth.  Another factor are fine stream substrates that tend to allow plant or periphyton growth, and possibly the added roughness of vegetation accumulations that would further reduce stream velocities also favor algal growths.  I would guess also that aggrading or braided streams with excess sediments and nutrients also might favor conditions for eutrophication.  As stream facets fill with sediment, conditions increasing are able to support organic growth and accumulation.  River meanders that have lost regular channel connectivity (sloughs) may also eutrophy more quickly, as the properties of flowing systems have been compromised.  Streams with roughly annual bankfull channel scouring and velocities that support coarse substrates, more dissolved oxygen and low to moderate temperatures are unlikely to eutrophy.  But I do not live or work in conditions where nutrient loading of flowing streams has been extreme.  If plant growth invade and overtake channels, a variety of physical, chemical and biological changes occur in how streams respond and process water, sediment, nutrients, habitat, etc. 
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The most present gas in the bottom sediments is methane, as the product of the anaerobic degradation of organic matter. In many cases (Baltic Sea) the eutrophication is caused  by anthropogenic factors, what is  not  exposed  due  to political reasons. Acoustics gives us the most effective ways to observe the whole process of production and the ebullition of the methane from the seabed. Due to high difference of the acoustic impedance of the gas and the water the gas  bubbles are easily detected by the echo-sounder. The whole process of expulsion of the gas  from sediment to the water and rising the bubbles towards the surface can be observed and quantified in detail by sonar.
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Methane bubbles in Lake Kinneret: Quantification and temporal and spatial heterogeneity
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I just want to estimate the contribution of algal dry weight to particulate organic carbon dry weight. I have calculated the ash free dry weight and Chl a of an eutrophic lake. Can you please suggest me a relatively better ratio, so that I can determine/estimate algal dry weight?
Thank you
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If you have only the numbers you mention in your question and no options for additional measurements, you can do the following:
-        The carbon to chlorophyll ratio in phytoplankton usually ranges between 20 and 50. So if you multiply your chlorophyll concentration data with 20 and with 50, you get a range for the phytoplankton carbon concentration in your lake.
-        Carbon makes up roughly 50% (40% - 50%) of the ash free dry mass of particulate organic matter. Divide the ash free dry mass of organic matter by two and you receive the total carbon concentration in your lake.
-        Then divide the numbers obtained for phytoplankton carbon by the total carbon concentration, and you receive the proportion of phytoplankton carbon in total carbon.
The biggest unknown is usually the carbon to chlorophyll ratio in the phytoplankton cells, which can be highly variable. So if data exist that are more exact than the range of 20 – 50 mentioned above, you should use them. It also would help if you have numbers for phytoplankton biovolume along with the chlorophyll data.
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I have read in several papers that lighter d13C(org) may be indicative of terrigenous input (landplant) and/or microbial activity (Biodegradation). Some scientists also use d13C(org) value as a proxy for paleoproductivity suggesting that lighter (more 12C) values are indicative of Paleoproductivity and eutrophication. I wonder, to what extent, d13C(org) could be used as a paleoproductivity indicator RELIABLY? Is there any published work on this issue?
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There is a lot of published work - though most of it in the marine environment. These may give you a start - but there are hundreds of papers linking d13C to productivity.
 Kemp A, GSoL Vol 116 1996,
Boyer et al, PPP, 306. 2013,
Goudie & Viles ESR, 113 2012
La Porte et al PPP, 276, 2009.
PPP is probably the best journal to start with some key word searches...
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, Water Quality Modelers
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Dear Motahareh
you can read this wonderful book
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Do you make a difference between marine, freshwater (and terrestrial) eutrophications? Do you model the fate of nutrients? 
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Hi, 
Thanks Alejandro and Diego for your answers and documents that I actually already knew. My objective was also to launch an interesting discussion on the subject. I fully agree Alejandro that LCA should remain different from other local methodologies. I also fully agree with the potential aspect of impacts in LCA. I however think that some interesting and useful improvments can be done to develop more consistent characterization factors.
The regional scale for eutrophication is a start but I'm sure we can go until the hydrographic sector that would be moore representative of the eutrophication issue. It could be really usefull to chose, for example, between two different spreading scenarios of sludge in a same country (in two differerent sectors). My idea is not to double with other methodologies but to made LCA adapted for specific questions we have at the territory level. 
Thanks for the discussion and I hope we'll be able to speak about these questions again. 
Regards
Samuel
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I conducted a study on our university's freshwater lake located in our nature preserve. Now, we are in the process of restoring it.
Can anyone recommend any important plants/trees needed to suck up nutrients and filter the water?
The water is very turbid (visibility is low at about 1-2 ft). P is limiting but about 0.04-0.06 mg/L and N is 1.02-1.40 mg/L, dominant aquatic plant spp is FW macroalgae Chara spp., and it is surrounded by Ardesia and Brazilian Pepper. There is a healthy population of eastern mosquitofish and large mouth bass, but there is a high amount of striped tilapia and african jewelfish.
Average depth is about 6 ft, max depth 9 ft. 
Let me know if you need anymore information.
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1.) BIVALVES--I did not see any mention about any of the 50 species of fresh water Florida native clams or fresh water mussels?  They are good filter-feeders.
2.) WHERE IS TURBID WATER COMING FROM?--No mention why the pond is so turbid-- is turbid water coming into the pond, if so, why not produce a kind of native Florida vegetation filter lining the stream into the pond with some native sedges or wiregrass?  It sounds like this pond is being fed by agriculture, road or lawn runoff? You will probably solve 90% of the pond problems when you fix the source of the turbid water going into the pond.
3.) POND EDGES--And what about the pond edges, solid native plants along all of the edges, or are there bare areas?  Three feet above and one foot below the water line should be covered with native vegetation
4.) EXOTIC PLANTS OUT--And chop down all of those exotic Ardesia ( if they are either crenata or elliptica) and the Brazilian peppers if you can, because their leaves dropping into the pond could be having an effect.  However if you have Ardisia escallonioides, that is a Florida native, so keep that.
5.) EXOTIC FISH OUT--And what about fishing out the exotic fish?  Mmmmm, fried tilapia barbeque?
Also, you did not mention the size of this pond? 
Basically you will known that you fixed your pond, when you can see to the bottom.   Keep experimenting and get a Secchi disk and measure the turbidity at least twice a month, to see how well you are doing on the turbidity.
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Dear all; 
Is there any instruction about using clay to cope with Microcystis (blue green algae) in lake? 
Thanks.
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Let's assume no malfunction of our YSI sonde, as we are very sure of that. Recently we had spiking chlorophyll a measurements in water from Duluth-Superior Harbor (western Lake Superior), ranging from 16.4-17.9 µg/L, clearly in the "eutrophic" spectrum for this system. A microscopic analysis on slides indicated very few algae specimens (expected for this time of year), including a lack of tiny cyanobacteria (which we first thought it might be). Looking for ambient red signals using fluorescence microscopy also didn't show anything notable. One thought is that something (perhaps leaf litter) is breaking down and filling the water with active chlorophyll or its byproducts (like phaeophytin). I welcome any thoughts or ideas on what could be causing this.
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