Questions related to Phytoplankton Ecology
For community studies like species succession, variation in composition, especially for plankton and benthos, what are the appropriate statistical methods? One such method is MDS with cluster overlay. Similarly what else can be applied for such studies?
I have been exploring data in the Agean sea from MODIS product normalized fluorescence line-height (nFLH).
In many control areas, I have noticed a strange pattern on the fluorescence line-height values. Does anyone know if this is due to a problem in the sensor?
I have a time series of monthly chlorophyll-a observations that spans from 1997 to present day. I have computed the p-value of the time series without removing the seasonality, and it doesn't quite show much of a trend. So, my question is, is the seasonality of the data affecting my computation, and if so, should I remove it? And, any recommendation on which methods that I should use to deseasonalise the time series.
I apologise if my question makes no sense. Thank you in advance.
These Imaging FlowCytobot (IFCB) images were taken during a December cruise in the Santa Barbara Channel during the Thomas Fire. They were imaged after tripping a fluorescence trigger. These species appear at the surface and at the deep chlorophyll max. The cells look like they are in various stages of dividing and were maybe pulled apart by the IFCB during intake. Any help with identification would be much appreciated!
please share your valuable understanding on the 'gap in knowledge' especially in freshwater phytoplankton study. How do it dis/similar with 'limitations in study'? Is there any relation with each other?
Thanks in Advance.
Anila P Ajayan
i am more interest to know what kind of hypothesis, question, or objective that each index usually answer. surprisingly that both indices has quite the same definition in a term of scribing the reason of using them to define diversity. i calculate both indices and i would like to discuss the results. simply my objective is to see if there are special and temporal differences in phytoplankton diversity among 8 sampling stations.
also i am interested to know what are the main objectives or questions of your researches that you answered using such indices. thanks
I am interested in citations that explore the relationship of phytoplankton with the reflective, absorptive, and refractive properties of water in estuarine systems or alternatively to direct measures of water clarity or light attenuation. I am interested in knowing whether or not changes in community composition could result in changes in water clarity or light attenuation. For example, changes in species composition might result in changes in the overall average size, shape, or concentration of accessory pigments in the water column which could alter the properties I mention above.
I would appreciate any citations, particularly review papers, that you folks might think would be useful. Although the focus of my interest is estuarine and marine, I would also appreciate freshwater citations. Thanks.
Am trying to extract exopolysaccharides from fresh water microalgae. So far I was unable to obtain polysaccharide precipitate in considerable quantity. Still I want to check if there is an enhancement in the production of polysaccharides against stress factors. For this, can I perform Phenol sulphuric acid assay with the supernatant obtained after centrifugation of the biomass? Will this method give result or must I do it only with an eps precipitate?
We found these organisms in gelatinous material, collected from small scale fishing nets in Cyprus coast. Nets were quite loaded with this mass. It was observed using a microscope (400x). Does anyone know what this might be?
Thank you in advance.
does somebody know to suggest me a reference study estimating/measuring the general relationship between PON (particulate organic nitrogen) and chlorophyll-a in marine phytoplankton? Even better, specifically for the groups of marine diatoms and cyanobacteria?
Thank you in advance,
Does anyone know these soil algae? They are isolated from biological soil crust in Bremen, Germany.
In the figure, there are 4 species (Non-Gel A1, 2; Gel A1, 2). The left one in each row shows their morphology on agar plate. In the microscopic image, I notice that they have different cell size. Algae (Gel-A1, and A2) both produce 4 daughter cells, and they have gelatinous colony on agar plate, while Non-Gel algae have flat colony. Scale bar stands for 10 um in the figure.
Can phycologists provide me any information from these algae? Like the genus they belong to?
This is a part of the research within my Master program. Thanks in advance~
By organic material I mean any kind of material that in theory may be found in the food waste, of both of plant and animal origin. I am trying to estimate what fraction of food waste, that if discharged to the marine environment, can act as "fertilizer" for phytoplankton.
But a low phytoplankton density during Monsoon. What all may be the other factors leading to variations in primary productivity of an aquatic ecosystem?
Thanks in Advance !
Desmids are very diverse in their morphology. To identify this group, kindly suggest me how to deal with it? Cosmarium, Euastrum, Staurastrum all these genera were closely identical. And also, how much light period should be provided to grow a Cosmarium strain in lab culture?
In order to do an experimental approach, we would like to use a substrate that is as equivalent to a natural substrate usually colonized by diatoms (calcareous and silicate-calcareous mix) as possible. In specialized bibliography we have found that artificial sandstone and glass-slides on bricks were used to this end, but wondered if there was any other method I am not aware of. We would also be thankful for any further publications on this subject you could recommend.
Thank you very much in advance.
It is look like a leaf under microscope, but it could be a plankton. Earlier I heard that it was a ciliate, but I didn't get this picture again in my samples. This too found in Bay of Bengal waters. Please help me to identify this specimen.
I apparently have ever heard that an tendency for dominant algal bloom-forming species was from diatoms to dinoflagellates in most parts of the world. Is that ture? Which paper have mentioned this view ? Thank you!
I have strains CCMP1524 and CCMP1528 growing in L1-Si and K-Si media. Cultures are in ambient light and temperature, 22C and 1500Lux, and 18C and 12000Lux, with and without shaking. The cultures are in good condition and reach exponential growth quickly, but will not form colonies!
Would anyone know a good article where I can find the gross primary production (total amount) of carbon per year?
On the internet, I find that may different numbers and most are from quite old research papers. It would be helpful to have a recent research paper in which they give the total GPP.
Algaebase mentions it as Syringidium Ehrenberg, 1845, nom. rejic. but also mentions that is currently recognized as a distinct genus and the holotype species Syringidium bicorne Ehrenberg is currently accepted taxonomically.
I have read
Hasle GR & Sims PA (1985) The morphology of the diatom resting spores Syringidium bicorne and Syringidium simplex , British Phycological Journal, 20:3, 219-225
but cannot find
Hasle, G.R. 1983. Proposal to conserve the generic name Cerataulina H. Perag. ex. Schütt over Syringidium Ehrenb. Taxon 32: 474-475.
Need help regarding this.
Today different wavelengths has been chosen to measure diatom optical density. Right now more and more articles select 625nm wavelength to estimate Phaeodactylum tricornutum dry weight. Does anyone know the reason to choose 625nm instead of 750nm or 600, 680nm? Or if you have any good recommendations?
The species was collected (in high density) from subsurface plankton tows (100 micron mesh size) in the Persian Gulf in autumn. Both colonial (max 3 specimens) and unicellular forms were present in the samples.
Water samples were taken from an estuary (Salinity: 15 ppt) and brown colony formed in the agar plates after 4 weeks of plating. Photographs taken at 40 X magnification. Size of the cells: 8-15 micron
Can anyone help me to identify this strange thing in thin section?
From mid-Permian in South China
Is that Algae?
Someone tell me fig.3 is Archaeolithoporella, but I think it looks diffrent.
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.
Owing to the tiny size of the Coccolithophores their turnover rate is pretty high. Dead cells are continually shed in the water column mixing with live ones and remain there for a long time. Is there a simple method to count dead and live cells?
I have grown P. gingivalis to an OD of 1.0 in BHI. I then carried out serial dilution to 107 and plated on agar. I repeated this severally but the results for each trial exhibit a range that can not be attributed to pipetting technique. I am pretty confident with my pipetting skills. What are factors can explain this inconsistency? Please advise.
When I search papers about phytoplankton grown on a series of irradiances, nutrients and temperature, I found Michaelis-Menten equation is usually chosen for Irradiance or Nutrients vs Growth rate fitting, but Eppley equation for Temperature vs Growth rate fitting, why? Michaelis-Menten equation could not used for temperature vs growth rate?
CANONICAL CORRESPONDANCE ANALYSIS
Dear friends, I would hereby like to inform you that i have a two year data set (monthly observations as data points) consisting of abundance (log transformed) 40 species of phytoplankton and 15 environmental variables.
My objective is to identify the seasonal patterns in environmental parms and species abundance.
I have tried the canonical correspondence analysis for analyzing this data to identify the linear combination of species scores with environmental variables. But, the results are bit complex and i need your suggestions for analysis (better ordination techniques if any) and the modifications in the same analysis (data as well as analytical steps).
I found CANCORSP, REDUNDANT, PCA, CORRESP analysis as the best methods for ordination. Please help me in this regard
can you help me with classified the following genes:
cymbella: Long= 5, Width=1.25
long= 4.25, width=1
Amphora: Long= 5.25, Width=2.25
Achnanthus: Long= 5, Width=1.75
Nitzschia: Long= 5, Width=0.5
Hi I’m culturing diatoms in conical flasks and they tend to stick at the bottom and the wall of the flasks. What is the possible method to get rid of the sticking cells from the flasks wall besides sonication and manual scraping? Any suggestion? Many thanks!
Zooplankton are, by definition, drifters in the ocean. Therefore, they are often associated with different water masses and can be ideal indicators for assessing ecosystem status. More specifically, what can they really indicate, how do we incorporate zooplankton indicators into ecosystem assessment framework, and how these indicators can be used in marine policy?
I have acquired the use of a Water PAM to measure Fv/Fm in concentrated samples of phytoplankton. In the instrument guide and throughout the published literature it is recommended to measure Fv/Fm on dark-adapted samples. Unfortunately, I can't seem to figure out how long I need to be keeping a sample in the dark before measurement. Some say 30 seconds, while others say that the sample should be "in the dark overnight". For sure there are species variations in what passes for photosystem II saturation after dark adaptation, but I am just looking for a decent overall estimate for freshwater phytoplankton. A 30-second incubation in the cuvette, in the dark, would be ideal. Would I get a substantially different answer if I incubated longer?
We are going to develop a software for drinking water plant technicians to identify phytoplankton.
I’m using specific primers to quantify Scrippsiella donghaienis (a phytoplankton species) in DNA extracts from sediments by real time PCR. When total DNA concentration is high, the melting curve shows a specific peak of Scrippsiella donghaienis at 82,5 °C. However, in sediments of low DNA concentration, I get a double peak (a very small peak of Scrippsiella and another higher peak at 88 °C). Do you have an explanation to this ? I attached 2 images of specific amplification and non specific amplification from the same test.
I frequently encounter tiny fast moving round microalge (?) species as a contaminant in Haematococcus culture when the culture is grown below 0.6 mg/L phophate conditions.
I suspect it to be some haptophyte but not sure.
It is a non-cuantitative study about diversity at genera taxonomic level of planktonic green algae and cyanobacteria in two continental water bodies of 6084 and 4540 m2. I interested in know about of sampling design: techniques for site selection in the water bodies, number of sites and sample volumen.
Zigetang Co is a meromictic endorheic saline lake without any glaciers in the catchment on Tibetan Plateau, which is directly located at the boundary of the Indian monsoon. The short chain n-alkanes C15, C16 and C17, likely derived from aquatic algae, plankton and photosynthetic bacteria, dominated most of the lake sediments. Howerver, we are not sure how to explain the source of these short chain alkanes. Do you have some ideas or some similiar papers discussing the short chain alkanes? Thanks a lot.
I am interested in studying the mutualistic relationship between phytoplankton and seabirds, and how it plays a key factor in sensing climate change in a marine ecosystem (the specific mechanism/s). I also want to determine how ecological imbalances can affect climate change regulation.
I found this sample(which is attached) along with the phytoplankton samples collected. Suggest me weather its a kind of plankton or some other thing. If its a plankton help me to identify its name.