Well that's a big question! :) The first thing you need to ask is "what kinds of bacteria are there?" What do you think? I'll tell you a bit about some of the different kinds of bacteria. Some bacteria live in the surfaces of things and "eat" off of them. For example, when you see a tree decaying in a swamp, most of that decay is happening because bacteria are breaking down the wood. Did you know that some bacteria can live without oxygen? It's true. A lot of them will die if they are exposed to oxygen, just like animals will die if they are not allowed breathe oxygen. Finally, there are bacteria which can live in both places. They can change their physiology (do you know what physiology means? Look it up and see what you find) for either living with or without oxygen.

So what is the next question? You now know that different kinds of bacteria live in different places. Did you know that the mud on the bottom of a swamp usually does not have oxygen? Now you have a clue about one of the environments in a swamp. What other kinds of environments are there in swamps? Why don't you tell me and write back with the answer. Good luck!

Bacteria are very diverse, much more diverse than are animals and plants. There are many types of bacteria that live in swamps. Just outside my window in the lagoon on campus, I did an experiment in my microbiology class to see how many different types of bacteria live in the lagoon. There were photosynthetic bacteria that use light to make energy and food as plants do; there were heterotrophic bacteria that use oxygen and food for energy and give off CO2 as humans do; there were anerobic bacteria that do not need oxygen to survive and in fact are often killed by exposure to oxygen; there
were magnetotaxic bacteria that orient themselves in the water and mud so that they line up with the earth's magnetic fields (and with the north and south poles of a magnet...I tried it!); there were bacteria that get energy from fermentation just like bacteria in beer and wine do; there were bacteria that produce methane which is a gas that we can burn for fuel to heat our houses. Just about every type of bacteria on earth lives in that lagoon, with some exceptions: bacteria that are found only in the deepest
parts of the ocean and bacteria that need to be in extremely hot water to survive (where would you expect to find these bacteria naturally?) are some of the exceptions.

In some swamps, there is so much heterotrophic activity going on (so many things using oxygen to make energy) that there is very little oxygen in the water and in the mud underneath. Many things cannot live in habitats with low oxygen, but bacteria are one of the few types of organisms that thrive in these environments! In fact, some swamps and lagoons have so much bacteria that the bacteria form floating mats on the surface of the water. These mats are full of all different kinds of bacteria.

What kinds of bacteria do you think live in soils? Would they be similar to bacteria living in swamps and lagoons or different? What are the major differences between these two habitats? How are they similar?