Questions related to Aquatic Science
at the Museum of Nature South Tyrol, in Bolzano / Bozen, Italy, we're keeping in aquarium for more than 10,5 years 3 American horseshoe crabs Limulus polyphemus.
What is the maximum longevity of American horseshoe crab in aquarium?
I'm working on cumulative risks assessment of lead, chronium, nickel in groundwater and drinking water.
To reduce CO2 concentration and increase pH value of RO permeate water a CO2 stripper system shall be used. The stripper system includes a packed bed column that provides required surface for air-water contact and an air blower.
The analysis of influent water is as follows:
Temp= 20 C
CO2= 64.6 ppm
HCO3= 4.9 ppm
CO3= ~ 0.0 ppm
How can I measure the concentration of HCO3 and CO3 and the pH value of the effluent product? The concentration of CO2 in the effluent can be determined according to the CO2 content of inlet air and Henry’s law.
To my knowledge, using carbonate equilibrium equations there are four unknown parameters include CT, CO3, HCO3, and H concentrations, while there are just three equilibrium equations.
If this equilibrium is correct,
CO2 +H2O <->H2CO3 <-> HCO3 + H <-> CO3+2H
it means that when CO2 is added then the equilibrium is shifted to the right, increasing HCO3 and H.
Could this lead to pH reduction?
Loss of species of Heleopera, Hyalosphenia, and Nebela and increase of species and numbers of Trinema, Corythion,and small Euglena should parallel physico-chemical changes in dessication.
I used dried and ground Sargasssum spp. to enrich surface sediments. Took sediment samples (that may have bits of Sargassum spp.) and determined chlorophyll-a spectrophotometrically. I am wondering if the chlorophyll-a could come from the dried Sargassum ssp., and not benthic diatoms.
Most studies using eDNA in freshwater seems to be focus on detecting fish species currently occupying a lake/river system. I have read that there is a rapid degradation of eDNA within days to weeks in the water. But am wondering if it would be possible to detect historical eDNA from fish in freshwater sediment to determine how pristine fish communities looked like, say >1-300 years back in time?
I would like to collect data for a review about development in the "lower" Crustacea: Decapoda, specifically shrimps or prawns classified within the Dendrobranchiata (penaeids and sergestids). I am particularly looking to collect information from studies reporting: (1) relative durations of different immature phases (egg/embryo, nauplius, protozoea, mysis, decapodid/postlarva) and/or stages within these phases (nauplius I, II, III, ...); and/or (2) how the number and duration of stages (and total development) is affected by temperature. I have been able to find a handful of relevant studies, although some of these are older and only give very broad ranges for stage durations. Any recommendations for studies/data sources would be greatly appreciated!
Fish nursery grounds are significant for the life cycle of fishes and frequently these grounds are not particularly well examined or the processes understood. The juvenile stage of fish is frequently considered to be particularly hard to work on
To calculate mean pH, you have to convert first to ion concentration, but the std. dev. you get cannot be converted back into pH (or at least isn't a logical number).
Sturgeon biologists - I am studying early life history of white sturgeon (Acipenser transmontanus), and we are in the early stages of building an individual-based model to determine why juveniles do not live past about 6 months of age (recruitment bottleneck). What are your thoughts about the most important mechanisms for survival at this age?
I have just recently encountered and read on the concept magnetoreception in salmons. So far, the way of observing or detecting such is quite complicated. I'm wondering what is the simplest way possible that would be able to observe this phenomenon in aquatic animals?
In what ways do they provide insight on the disposition of a given body of water? Are there certain characteristics that are common among these organisms that allow them to demonstrate the quality of the water?
I have carried out plankton sampling in a natural stream and I can't see any organism? Is this situation feasible in nature? What can be the reasons?
I am working on population genomics of freshwater shrimp, Paratya australiensis. I am trying to extract high quality, high molecular weight DNA (~3ug, >50kb); from Paratya for RAD-sequencing. I have tried different extraction methods on fresh and frozen samples so far, e.g. Spin-Column extraction, CTAB extraction and Salt extraction. Besides, I have also tried an extended gDNA extraction procedure by incorporating a salting out step prior to phenol/chloroform cleanup. But unfortunately these methods have all produced what appears to be a smear of degraded DNA rather than high molecular weight band on agarose gels. Can anyone suggest me any other procedures that might help?
We have been monitoring a temperate lake during the winter and observing Daphnia under the ice, when normally they would not be found in the water column. Some of which still have asexual eggs. The system is hyper-eutrophic which is leading us to think perhaps food conditions still permit growth even though temperature is cold.
Has anyone else observed Daphnia in winter or under the ice in lakes? Thanks.
I am working with Daphnia magna and meet serious problems:
1/ 24 hours after feeding, medium started to be oily and have opaque light green (fig 2).
(3 months ago, I fed the same concentration of food (Chlorella vulgaris and YTC) but medium have very clean light green color after feeding 24 hours).
Concentration of food can be clearly observed in fig 1.
2/ Daphnia suddenly have smaller size than before although feeding is same.
3/ Daphnia have many eggs (brown eggs) but they stay long time in brood chamber until turn into "white eggs" (white color) (fig 3) and broken (death). So they can not hatch into babies.
Maybe it's caused by brood parasites? How can we solve this problem?
I am very thanksful for your help.
I am searching for an organism that is also easy to breed in the aquarium and reproduces relatively quickly (say up to 2 or 3 months is ok). I am open to both salt- and freshwater organisms!
Hello! I would like to carry out experiments with live bithyniids (Bithynia spp., especially B. tentaculata and B. leachii), but I would need to separate the sexes for meaningful population dynamics analyses. Is there a reliable way to separate males from females in vivo (based on either or both shell or soft body morphology) without damaging the snails? I need them in good health for my experiment! :) Thanks a lot!
I am looking for any studies that has analysed what happens if a marine reserve is again opened to fishing. Any tips highly welcomed?
We are planning to buy a new licence for Ethovision from Noldus, but we are not sure about its practical use for crayfish and fish.
I need some information on weights for marine investigations. Can you inform me - what types of weights do you use aboard research vessels at the sea? Are there any weights with resolution 0.1 g or higher? We used Pols with such resolution long time at PINRO, but now Pols is not exist. I will grateful if you can provide model name and producer (and site where it will be possible to see it).
I'm trying to calculate secondary production of freshwater benthic communities. Some times (nearly in 50% of cases) I got negative numbers. Does it means that destruction in bigger that production?
I'm want to understand if I have done the mistake or not.
We use a short range DIDSON in Redwood Cr, and a long range ARIS in the Mad R. Redd surveys are independently counted in Redwood Cr. To date (3 yrs of data), we are not seeing any agreement with sonar counts and redd counts for Chinook salmon and steelhead trout. The redd counts are negatively biased, even if you take into account that not all salmon passing the sonar beam will spawn (pre-spawn mortality). I know there is similar work on the Secesh R in Idaho, and I am wondering if any other place has a similar study going on and what their results might be.
Recently, I downloaded ZooImage software for image analysis of freshwater zooplanktons. I want to know if anybody has used this software and whether this zooImage software is reliable ?
I'm currently working in an area of rapid sedimentation, and I wonder which other factors can influence the density and distribution of mangrove species? I know the tide is one of those.
there are several advancements in the analysis and monitoring of freshwater bodies in all over world; but i need to know the current advancements in the same. like modelling, analysis, prediction, statistical applications etc., can anyone help in this regard
Production of live food is not up to our expectations in alkaline water. Further the dosage for use of organic and inorganic fertilisers under this condition is also not clear.
When working with CG-TSD to analyse OPP in river water and groundwater is there a established range of concentrations necessary to work with? The European Union have established a concentration of 0.1 ug/L of those pesticides in water.
Currently my research project is focus more on fecundity aspect of Macrobrachium rosenbergii. The research main objective is to find the comparison value of potential fecundity form the target locations. However, my main concern now is how much individual sample that I should take off? Should it be more than 30 individual sample?
I tried to use the box model to estimate the salt budget of Iraqi marshes, which explained by the equation concentration of salt input - concentration of salt yield (plus/minus) changes in ground water recharge/discharge. I did the calculation for 10 months period but I think there is a missing content to this equation! Please check the attached file to have a better clue. Thanks in advance
Generally how is batch fecundity expressed? Is it calculated from the total of nos. of hydrated eggs from upper, middle, and lower part (sub samples) of the any (left or right) ovary or average of the results of three sub-samples as done in total fecundity calculations.
I am trying to isolate and cultivate strains of prasinophytes, cryptophytes, haptophytes, pelagophytes. The idea is to use this cultures to identify pigment profile and compare to HPLC data from field samples.
For observation purpose some 15 juveniles were placed in air tight plastic bag.What is the maximum number of days white leg shrimp vannamei could survive without aeration, feed when placed in closed airtight plastic bag with water from fish ponds?
How can we quantify the seaweeds as Caulerpa sp. or lithothamnion sp. (no. of individuals per unit area) using quad rate frame for the calculation of Shannon index?
I want to study on benthic invertebrates and their relation on shrimp
catch, but how i can estimate the relation? What statistical test should i
use? Is there any statistical way to estimate a model with data of
shrimp catch and biomass of benthic invertebrates?
I am interested particularly in assessment of ecological status of hypersaline lakes according to the WFD. If there is a full description of a method based on aquatic macrophytes, I would be grateful. Any suggestions and commets concerning status of hypersaline lakes and/or reference conditions are also welcome.
I would like to use Ceriodaphnia cornuta and Bosminopsis deitersi for a series of experiments but the problem is that they tend to die within a week. I'd used "aged" tap water & distilled water as the culture medium. I monitored the pH, temperature etc. but still can't figure out what's the real problem. Any suggestions?
Decreased light transparency is often associated with higher biomass/chlorophyll production and consequently reduced euphotic zone.
Limited material preferable, power equipment unfortunately not a viable option
I want to conduct lab experiments on sediment nutrient fluxes under aerobic and anaerobic conditions.
why is S. galilaeus one of the tilapiine species with a high occurrence or likelihood of hybridization? is there an ecological reason?
I have received information that a fishing club has been encountering large numbers of freshwater jellyfish in a dam in NSW, Australia. These organisms are considered to be rare and little is know of there biology and ecology.
Specifically those used to handle grab sample data, but ability to handle "continuous" data would be a distinct advantage. Which products work, which ones allow integration with hydrometric data or databases, and how good are the GIS and visualisation tools?
I was wondering if there is any website or portal where I can get information on the specific locations of marine aquaculture farms in Europe, as well as on their production per year.
In a experiment, I have to estimate chlorophyll before and after the experiment and estimation cannot not be done at the same place.
So, is it possible to preserve the spirogyra (in what preservation and for maximum how long) for the later estimation for chlorophyll? Although I know, its good to estimate the chlorophyll content at the same time otherwise the chlorophyll content starts degrading.
I would like to study environmental bacteria under starvation. I would like to dilute a freshwater bacterial concentrate with a medium without any nutrients during several hours incubated on different temperature. What kind of water can I use in order to put the bacteria in starvation condition. Do you think that freshwater ultra-filtrate sterilized by autoclave would be suitable? Or physiological water?