Eutrophication - Science topic

As per I know, Acrylic (PMMA) and thermoplastic polymer (PC-7) materials would be a good choice and economically beneficial solution to build a UV permeable enclosure system specially for a shallow waterbody. oh, they are long lasting, recyclable and easy to operate.

Algal blooms refer to the rapid growth of algae in water, which can deplete oxygen, reduce water quality, and sometimes produce toxins. Red tides are a specific type of algal bloom that discolors the water, often red, due to pigments in certain algae like dinoflagellates. These blooms can release harmful toxins, posing risks to marine life and human health.

Could You tell me how much the article publishing charge is?

In my opinion, your hypothesis is a plausible one. However, more investigation is needed to fully understand the complex interplay between coastal erosion, nutrient leaching, and algal bloom activities, considering that various other factors, such as changes in water temperature and sunlight levels, can also cause algal blooms.

We have done some research about this issue in the Ría de Vigo, an embayment in NW Spain, in a region affected by wildfires every summer, and where algal blooms are a major concern. We carried out two experiments (one in summer, and another one in winter), where ash leachate from a forest fire was added to microcosms containing water from the Ría de Vigo. In the summer experiment, when the water was rather oligotrophic, the concentration of the ash leachate added was directly proportional to the response ratio in chlorophyll a concentration (used as a proxy for phytoplankton abundance). Although we don't have taxonomic data about the phytoplankton, we do have 16S metabarcoding data from those experiments, and the data showed that some bacterial taxa, including potentially pathogenic Vibrio, increased their relative abundance after ash-leachate additions, with respect to the control microcosm. The reason for the changes in bacterioplankton community composition are not very clear, as they might be either caused by nutrients contained in the ash directly, or by remineralization or exudate products from phytoplankton. Either way, phytoplankton seems to be directly affected by the ash leachates.

Furthermore, in October 2017 there was a massive wildfire around the Ría de Vigo, which was followed by a drought that lasted until December. We started sampling water in a time series, which started right after the fire and where water was sampled from different stations in the embayment, roughly every two weeks. When it finally rained in December, the sample closer to the mouth of a river, which might be the most affected by runoff, showed its greatest surface Chl a concentration, together with changes in bacterioplankton community composition. Please see:

and the third chapter of this PhD dissertation:

Total nitrogen can be measured after oxidation with potassium persulphate. The method uses heating in an autoclave, but a pressure cooker for kitchen use is sufficient. An electrode that can measure nitrate, and is used together with a pH meter, is expensive, but if many analyzes are to be carried out, it can perhaps be defended? https://www.coleparmer.com/i/cole-parmer-ise-electrode-nitrate/2707710 With this electrode, you can measure NO3 directly, or Tot.N as nitrate. There are also kits that measure different forms of N colorimetrically. The reagents come in tablet form and are easy to dose. Used spectrophotometers may be found on Ebay

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

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.

Personally, I strongly recommend this article which will certainly be useful to you.

Regards

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

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

Available on : https://www.geosociety.org/gsatoday/archive/24/8/article/i1052-5173-24-8-4.htm

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)!

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.

A very good explanation and cautions for those who are dealing with plant nutrients including myself. Yes, chlorine is the most ignored micro-nutrient!

Thank you Mohamed Ben-Haddad . :)

please check the links

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.

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

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

For eutrophication assessment of lacks, the data required are water clarity, nitrogen, phosphours and chlorophyll.

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

http://www.chnep.wateratlas.usf.edu/upload/documents/EutrophicationAndHABs.pdf said that it range from less than 1 to 10

less than 1: 1 to 6 : 1

high ratio (above 30) still supported the occurrence of eutrophication

Hope this one helps you

Good luck

Fish kill, oxygen depletion, little sunlight which reduces the activities of phytoplantons thereby affecting the entire ecosystem.

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.

Yes, you think correctly. The percentage of organics will increase

https://www.nature.com/scitable/knowledge/library/eutrophication-causes-consequences-and-controls-in-aquatic-102364466/

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

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.

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

Most probably due to increase of nutrients

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

Sincere thanks resp.Dr. Ghosh and Dr. Mitra for valuable remarks

All pollutants are dangerous in environment.

This research shows the effect of soil type on nutrient loss

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.

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

Abhishek Mukherjee and Weifei Yang thank you so much

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.

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.

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.

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.

Sewage disposal in oceans increases BOD and decreases DO

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

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.

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.

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.

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.

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

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..

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.

Dear, have look at very interesting attached PDF.

I prefer to use a commercial test kit if 50 cent/test is considered cheap.

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

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

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

    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 

Lathika:

Kindly provide scale and better focused pictures.

Best

Syed

please see the information that provided by DR. Ton

thanks for sharing this Atlas.

regards

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

Thanku Dr. Clinton  Rissmann.

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 

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.  

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.

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.

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. 

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. 

Methane bubbles in Lake Kinneret: Quantification and temporal and spatial heterogeneity

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.

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...

Dear Motahareh

you can read this wonderful book

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.