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In areas that have permanently frozen
ground, tundra ponds are formed. In these areas, the ponds form
where the ground has been thawed. Similarly, where the ground has
too much limestone, beneath the surface of the soil, sinkhole ponds
are formed. It happens when the underground water dissolves the
limestone and the ground sinks. A pond may form where the ground
has sunk. In the United States, there are many such sinkhole ponds
in Florida and Indiana.
When a slow moving stream widens as it
flows over a gently sloping landscape, meadow stream ponds are
formed. This kind of pond has plenty of life. Riverine ponds are
formed where the streams have stopped flowing through old channels.
They also occur where deposits of soil prevent water from entering
channels.
Dependence on nature
Ponds constantly undergo change. Depending on the rainfall in
the region for the year, water levels may rise or fall. As the water
level changes, the type and amount of plant growth also change.
Again, depending upon the amount of plant growth, the number of
animals also varies. Therefore, they are dependent on natural forces
for their maintenance. For instance, floods and movement of ice may
deepen ponds.
Flora and fauna
Ponds have a good variety of plant life and animal life. The
wind and stream carry in eggs and seeds, which develop into various
forms of life. Birds, fish, crayfish, frogs, turtles and insects are
some species of animal life that may be found in ponds. Many
microscopic plants and animals thrive in ponds. Rooted plants may
also be found in plenty in ponds.
What thrives in a pond is determined
largely by the soil, location and the quality of the water in a
pond. For example, ponds in tropical areas may boast of a different
kind of flora and fauna than those found in the ponds in the Arctic
regions or in mountain ranges.
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