5. Freshwater ecosystems : are one of the types of aquatic
ecosystems that exist on planet Earth.
They are known as "fresh water“ because they are formed water
with low salt concentration. In general, they have less than 1%
sodium chloride.
There are different types of ecosystems composed of fresh water,
including lakes, lagoons, rivers and flooded plains.
In general, these can be divided into two groups: lentic
ecosystems and lotic ecosystems.
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6. The lentic ecosystems are those formed by still or slow moving
water, as happens with lakes, lagoons, ponds, natural pools,
swamps, and other flooded plains.
On the other hand, the lotic ecosystems are those that have fast-
moving waters, such as rivers, streams, streams and other water
currents.
The fauna and flora in these ecosystems is very rich and varies
from one area to another. Includes crustaceans, aquatic plants
such as algae, different species of fish, insects such as dragonflies
and mosquitoes, waterfowl, among others.
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7. Lagoons and lakes: Characteristics
-They are static or semi-static bodies of water.
-Can measure a few square meters or thousands of square kilometers.
. Many are seasonal, which means that they appear and disappear depending on the seasons. Others are
permanent and have existed for thousands of years.
. Three zones are distinguished: the littoral zone, the limnetic zone and the deep zone.
-In the littoral zone, the water is warmer. This is because this is the shallowest part of the lake or the lagoon
and, therefore, can absorb more solar radiation.
-The limnetic area is under the literal zone. Due to its proximity to the surface, it receives enough sunlight
but not so much heat.
-The deep zone is the coldest and darkest of the lake or the lagoon. Also, in this area, the water is denser.
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8. Flora and fauna
The fauna and flora vary depending on the layer of the lake. In the littoral zone, there
is a great diversity of animal and plant species, including floating and rooted aquatic
plants such as some green algae.
Also, you can find aquatic snails, clams, crustaceans, fish, snakes, turtles and birds like
ducks. It is also common the presence of insects, such as flies and dragonflies.
In the limnetic area, there is plankton, both the plant (phytoplankton) and the animal
(zooplancton). These are small organisms of vital importance to the food chain in lentic
aquatic ecosystems.
The presence of these beings allows the survival of different species of fish that
inhabit the limnetic area. These fish feed on plankton, invertebrate organisms and
sediments found in lakes.
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9. Ponds characteristics
-The ponds are bodies of lentic water.
-They are shallow water.
There are four zones: vegetation zone, open water, surface and swampy bottom.
-The dimensions of the pond depend on the time of year. Many ponds are produced by
the flooding of the rivers during the spring and disappear with the droughts during the
summer.
Fauna and Flora
The fauna includes snails, fish, aquatic insects (such as mosquitoes and some species of
beetles), frogs, turtles, otters and some species of rats that live near the area.
Also, you can find large fish and alligators. Waterfowl are common, highlighting ducks and
herons. As for the flora, green and brown algae are typical.
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11. Flooded plains: Characteristics
-The flooded plains are territories covered by shallow waters, which allow the development
of aquatic silvers.
-The marshes, swamps and floods are part of this group.
Fauna and Flora
The flooded plains are rich in hydrophytic plant species, which are those capable of living in
areas where the humidity concentration is high. Among these species are lilies, bulrushes
and sedges.
Of all the aquatic ecosystems, the flooded plains are those that have the greatest diversity
of animal species. The fauna includes amphibians such as frogs and toads, reptiles, birds
such as ducks and wading birds, insects among which are the dragonflies, mosquitoes,
mosquitoes and fireflies.
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12. Rivers and other water currents: Characteristics
-The water currents originate in high areas, such as mountains.
-They can arise by the action of groundwater that rise to the surface as springs, by
the melting of perpetual snow or glaciers, among others.
- They follow a course that ends in another bigger river, in a lake, in the sea or in
the ocean.
-The temperature is lower at the origin of the river than at its mouth. Similarly, it
has higher oxygen levels at the source point.
-Water is usually clearer at the source than at the mouth. This is because the river
collects sediment in its course, so the water tends to get swampy.
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13. Flora and fauna
The flora and fauna of the water courses varies depending on the river area. At the
origin, fish such as trout are found, which withstand very low temperatures and require
large amounts of oxygen to live.
In the middle part of the course, there are several plant species, among which green
plants and algae stand out.
The water turns dark because of the sediments at the mouth of the river. For this
reason, less light can cross the aquatic surface, which causes a decrease in the diversity
of flora.
In this area, fish that do not require high concentrations of oxygen live, such as catfish
and carp.
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125. Natural salt pans or salt flats are flat expanses of ground covered with salt and other
minerals, usually shining white under the sun.
They are found in deserts and are natural formations (unlike salt evaporation ponds,
which are artificial).
A salt pan forms by evaporation of a water pool such as a lake or pond. This happens in
climates where the rate of water evaporation exceeds the rate of precipitation, that is, in
a desert.
If the water cannot drain into the ground, it remains on the surface until it evaporates,
leaving behind minerals precipitated from the salt ions dissolved in the water. Over
thousands of years, the minerals (usually salts) accumulate on the surface.
These minerals reflect the sun's rays (through radiation) and often appear as white
areas.
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126. What are Salt Pans?
A shallow container or depression in the ground in which salt
water evaporates to leave a deposit of salt.
How are salt Pans formed?
A salt plain (also known as a salt pan or salt flat) is a flat area of
ground covered with salt and other minerals. They are usually
purely white. ... When the water dries up, the minerals stay left
behind on the surface of the ground.
Over thousands of years, the minerals (usually salts) build up on
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127. Where are Salt Pans found in India?
The majority of India's salt production can be traced to
one region, the west central-state of Gujarat.
With more than 50 percent of salt workers located in
Gujarat, the state accounts for almost three-quarters of
the country's annual salt production.
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128. Natural salt pans or salt flats are flat expanses of ground covered with salt and other
minerals, usually shining white under the sun.
They are found in deserts and are natural formations (unlike salt evaporation ponds, which
are artificial).
A salt pan forms by evaporation of a water pool such as a lake or pond. This happens in
climates where the rate of water evaporation exceeds the rate of precipitation, that is, in a
desert.
If the water cannot drain into the ground, it remains on the surface until it evaporates,
leaving behind minerals precipitated from the salt ions dissolved in the water. Over
thousands of years, the minerals (usually salts) accumulate on the surface.
These minerals reflect the sun's rays (through radiation) and often appear as white areas.
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129. Why are Salt Pans important
The location of these salt pans is important because they act as
natural barriers to prevent flooding in Mumbai.
Along with mangroves, salt pans hold the seawater from entering
the city and stop flooding.
They are visited by several species of birds and different types of
insects thrive on them as well.
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130. How do you make salt in a salt Pan?
The process involved solar evaporation of seawater,
followed by artificial evaporation of salt using the open-
pan technique in structures known as 'salterns'. Inland
salt production.
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131. Why is Salt Pans obtained from Salt Pans?
Common salt is obtained in huge quantities through a process
called evaporation.
In this process, seawater is filled in large pans in left undisturbed
for some time in open yards during which the water gets
evaporated and salt remains in the pit.
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132. When Sea water is evaporated what is left behind?
Water molecules that evaporate become a gas called water vapor.
Only the water evaporates, leaving the sodium and chloride ions
behind.
The sodium and chloride ions attract each other and re- form salt
crystals
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133. Examples:
The Salar de Uyuni in Bolivia is the largest salt pan in the world. It contains
50% to 70% of the world's known lithium reserves.
Etosha National Park in Namibia, is another prominent example of a salt
pan.
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134. Hydrothermal Vents
A hydrothermal vent is a fissure on the seafloor from which
geothermally heated water discharges.
Hydrothermal vents are commonly found near volcanically active
places, areas where tectonic plates are moving apart at spreading
centers, ocean basins, and hotspots.
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135. Scientists first discovered hydrothermal vents in 1977 while
exploring an oceanic spreading ridge near the Galapagos Islands.
To their amazement, the scientists also found that the
hydrothermal vents were surrounded by large numbers of
organisms that had never been seen before.
These biological communities depend upon chemical processes
that result from the interaction of seawater and hot magma
associated with underwater volcanoes.
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136. Hydrothermal vents are the result of seawater percolating
down through fissures in the ocean crust in the vicinity of
spreading centers or subduction zones (places on Earth where
two tectonic plates move away or towards one another).
The cold seawater is heated by hot magma and reemerges to
form the vents. Seawater in hydrothermal vents may reach
temperatures of over 700° Fahrenheit.
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