Questions tagged [limnology]

The science of inland waters, posts on Biology SE should focus on the biological aspects of this discipline.

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How does the ice layer in frozen lakes acts as insulation? [closed]

Under very low temperatures, only a top layer of ice forms in a lake. I am reading "Life: The science of biology", by Sadava et al. The authors explain the phenomenon by saying that 1) ice ...
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Fresh Water Fish Identification

A couple of days ago I just adopted a group of 7 fishes, 2 inches long each, orange-pinkish color, a black dot before the tail, very fast, active and peacefull. Looks like a kind of tetra fish. Anyone?...
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Why this decay term in Anaerobic Digestion Model?

I am reading about the AM2 model, which appears to be a simplified version of the ADM1 model for modeling anaerobic processes. The author of this doctoral thesis extended the simpler AM2 model by ...
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Lab device to periodically, automatically transfer zooplankton between containers

I need a device to periodically draw a sample of transfer small aquatic organisms from one container to another without crushing/killing them. Each sample would be on the order of 10ml. My sketch of ...
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Movement of Common Jelly Fish

Among the different types of movements in the bodies of various organisms, the movement exhibited by jelly fishes are very unique and peculiar in some ways. I can't understand how to classify the type ...
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Are there taxonomic keys for members of the family poeciliidae in America?

I wish to know what are the taxonomic aspects necessary for the identification of certain species of poecilids, specifically what is the role in the counting of rays and spines and also the ...
2 votes
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What terrestrial trait makes cetaceans so successful in an aquatic lifestyle?

Intuitively, I would expect that an organism that has lived in the ocean for millions of years and can breathe underwater should outcompete any newcomer that is not fully adapted for oceanic life. It ...
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Are there any natural forms of aquatic vegetation which do not stand up in water?

We are carrying out some experiments where we study influence of underwater vegetation on waves. Unfortunately, the stalks of artificial 'vegetation' which we have seem to be too dense (or too stiff). ...
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Why is this giant water bug out of the water?

I recently took a picture of a giant water bug actually out of the water. Every instance that I have seen these of critters they have always been in the water (sometimes even feasting on frogs), but ...
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What species left these underwater eggs?

While inspecting some plants planted about 1.5 ft underwater in my pond, I noticed what appeared to be eggs on many of the plants. Note that the eggs are the white, oblong, opaque things. The clear ...
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How could a water boatman bug get in a place with no water?

I built a pond in my backyard. Before I even topped it off, I started finding water boatman (Corixidae) swimming in there. Note that the nearest body of water from my home is 30 miles away, and its ...
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Sediment Size and Mayfly (Explanation + Literature)

I am doing investigation into association of sediment size with the movement of mayfly nymphs in a choice chamber, sampling the organisms from a stream. I will be doing a chi square test to determine ...
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How can animals that rely on SONAR not see color? [closed]

Humans can sense colors with acuity and can distinguish them because of the light of different spectrum that follows into their eyes. Not its also said that sound is different for different colors, ...
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What kind of animals are these little creatures?

I have 3 tanks. 1 with my fishes and 2 other are technical. The smallest one is 0.5l and I'm using it as trash bin where I put dead plants and algae from main aquarium and it has sand from the see at ...
5 votes
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Are there adaptations in tropical fish to compensate for less oxygen in water?

Warmer water means that the amount of gases- especially oxygen- dissolved in it reduces, since solubility of gases in a solution in most cases decrease with an increase in temperature. I'm interested ...
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How many Watt-hours can an electric eel produce in a day?

Electric eels are cited as being about to produce about 860 watts of energy. But I haven't been able to find information on how long they can sustain their charge. https://www.youtube.com/watch?v=...
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Do electric eels produce current as they just move about, and how/why?

https://www.youtube.com/watch?v=y9wktSQdyaE This video demonstrates how an electric eel can supposedly produce up to 800 watts, and power a Christmas tree, which is very topical (a late Merry ...
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WC small organisms ID?

I have reached the end of my Winogradsky Column experiment, but out of interest I have kept them for a little longer. I have noticed small bug- and worm-like organisms appearing in some of my columns. ...
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Why do diseases in the tap water of developing countries affect people from developed countries more?

My siblings and I went abroad to a country that doesn't have drinkable tap water, but we did not know this at the time as the people who lived there used to drink it all the time with no issues. One ...
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How do fish persist in the upper parts of mountainous rivers with waterfalls?

I was recently traveling in a remote mountain region and hiking alongside a very small river. What caught my attention was the fish in the small ponds under the waterfalls. These ponds were just a ...
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Strange planarian/leech like creatures found with California blackworms

I've been trying to ID these things myself but to no avail. They came with a shipment of California blackworms from Florida. I've heard so many ID's and apparently it's not uncommon to get these ...
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Did humans evolve the ability to swim? Or is it just luck that we are able to swim?

Many animals like ducks have evolved features to be able to swim. Even not so aquatic animals like a tiger evolved so that its feet can act as paddles. In humans I don't see any direct feature that ...
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Will ammonia continue to accumulate in an aquarium tank if a strong antibacterial or chlorine is added to the water?

I've always wondered what would happen if dead plants and fecal matter lay in chlorinated waters and/or waters treated with strong antibacterials or antibiotics. I've heard that aquarium tanks ...
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Which animal dug this 5 cm diameter hole deep into mud and build a large mound around it?

I noticed the large structure below today at the edge of a very small pond in northern Taiwan lowlands. It is June and it has rained a bit the past few days, and this 15 cm mud dome with a 5 cm ...
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What is a false crocodile?

On the wikipedia page about crocodiles crocodiles are called true crocodiles. Does this mean there are (or where) false crocodiles as well? Crocodiles (subfamily Crocodylinae) or true crocodiles ...
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Is this aquatic plant duckweed or something else?

This plant has been growing in my pond for quite a time now. It multiplies in large numbers rapidly. Some told me it is duckweed or is it something else?
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What does this skull belong to?

I was cleaning out my pool with a leaf scoop the other day and found a small object, which I assume to be a sort of skull or cartilaginous structure of something that had died. I live in Sydney, ...
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Can someone identify this creature?

I discovered a few of these while cleaning an outdoor fish pond north of Sacramemto California. What is this?
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What are these tiny creatures swimming around my aquarium?

I was checking out my aquarium today, and decided to scoop out a water sample and take a look at it more closely. What I discovered were numerous, very, very tiny white worms (?) swimming around in ...
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Why doesn't alum coagulate my cyanobacteria?

My collected rainwater has a pronounced blue-green tint which I believe to be due to the presence of cyanobacteria. I have been trying to remove the cyanobacteria using aluminium sulphate, but it ...
4 votes
1 answer
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Do unique communities of bacteria form inside water storage in plants?

I assume that plants, like animals, have an ability to fight off bacteria that invade their cells (support: here and here. However, water often harbors quite a bit of bacteria in even unsuspecting ...
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Shrimp in rainwater puddles [duplicate]

After rain, we often find shrimp-like creatures in the puddles left on our concrete patio. We have also found them in the cat's water bowl (on the same patio). They are pink in color, and around 3mm ...
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What is this trilobite-like creature?

This was found under a rock in a freshwater creek in Maryland. Stayed like this for while, then stretched out long, then contracted, and then JUMPED off the rock back into the water. Looks like a ...
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1 answer
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Does human organism consume water or is it only used as solvent?

Dune (novel) describes a body suit called Stillsuit: a stillsuit is a "body-enclosing garment" of Fremen design which performs the "functions of heat dissipation and filtering bodily wastes", ...
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Land Shrimp Sighting (Western Europe): What is it?

This approx. 6cm long insect was moving rapidly across the asphalt in a wavy/jumpy motion. It makes me think of a shrimp. It has a kind of widened head like a hammerhead shark. I got two shots with my ...
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Where does the mass come from when you grow plants in water?

How do plants like green onions seem to grow forever when put in jar of water? I understand that plants get a lot of their carbon from the air (as per this question) but surely they need more than ...
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I want to know the name of this water plant?

Above is an image of an unknown plant. It grows without any care.
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Can an Ichthyologist identify this Canadian freshwater fish?

This will be very simple for a lot of you! But I been getting mixed answers about his catch. Is this a chinook salmon or brown spotted trout? Caught in Angus, Ontario, Canada. (Hwy 90 Bridge) I ...
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What is this plant/creature in my freshwater aquarium?

I've been noticing these really small creatures (or plants, I'm unsure) in my tank recently. They measure less than 1cm in length and I've only seen them at the bottom of my tank; some attached to the ...
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Why do we drink clean water [duplicate]

Most of the street/feral animals (cats, dogs, cows, some wild animals too) drink tap water or dirty water, but it doesnt seem to affect them. So, why do humans drink pure water?
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What kind of fish is this? Spotted or largemouth?

I don't know if this is a weird looking largemouth bass or a spotted bass. It was caught in southern Oklahoma. Please help! Thanks.
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How does eutrophication yield lower levels of dissolved oxygen? [closed]

Where do the oxygen go? Is it consumed by a particular species? Is just not enough being made? Please explain.
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Nutrient limitation in terrestrial and freshwater ecosystems

In terms of primary production, it is often described in textbooks that nitrogen is the most limiting nutrient in terrestrial ecosystems, while phosphorus is the most limiting nutrient in freshwater ...
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The effect of depth on net primary production in aquatic ecosystems

The figure shows the relationship between the water depth and net primary production (=P-R). I want to know why the production (P) initially increases with water depth near the surface? I have seen ...
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Calculation of saturation of carbon in surface waters

I've been looking at some journals lately that look at carbon emission from lakes where some lakes act as sources and other act as sinks. The paper that I have been looking at is http://www3.nd.edu/~...
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