( Freshwater Biomes & aqeous environments).pdf

1. Freshwater Biology
Introduction and freshwater biomes

2. Freshwater Biology
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The scientific biological study of freshwater
ecosystems
Seeks to understand the relationships between
living organisms in freshwater and their physical
and chemical environment.
It is branch of Limnology i.e. “study of inland
waters”. It is often regarded as a division of
ecology or environmental science. It covers the
biological, chemical, physical, geological, and other
attributes of all inland waters (limnic waters).
Inland: any of the waters (as lakes, canals, rivers, watercourses, inlets, and bays)
within the territory of a state as contrasted with the open seas or marginal
waters bordering another state subject to various sovereign rights of the
bordering state.
Differs from Oceanography : also known as oceanology and
marine science, is the branch of Earth science that studies the ocean.
Freshwater is defined as having a low salt concentration — usually less than 1%.

3. Application of freshwater
biology
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The discipline is also widely used in a
number of industrial processes such as
sewage treatment and water purification
which utilize biological processes to effect
purification.
Water flow is an essential aspect to
species distribution and influence when
and where species interact in freshwater
environments.

4. What is Freshwater?
• Key distinction: salinity = salt content of
the water

5. Numerical definition of freshwater
• Fresh water can be defined as water with less
than 500 parts per million (ppm) of dissolved
salts.
Freshwate
r
Brackish
water
Saline Brine
0.05% 0.05–3% 3–5% 5%
Just as per cent means out of a hundred,
so parts per million or ppm means out of a
million. Usually describes the concentration
of something in water or soil. One ppm is
equivalent to 1 milligram of something per
liter of water
1ppm = 1/1000000 = 0.000001 = 1×10-6
1ppm=1mg/liter of water= 1 milligram of something per kilogram soil (mg/kg).
One ppm is equal to 0.0001%:
Other sources give higher upper salinity limits
for fresh water, e.g. 1000 ppm or 3000 ppm.

6. Where is freshwater?
• Fresh water is naturally occurring water on the
Earth's surface in ice sheets, ice caps, glaciers,
icebergs, bogs, ponds, lakes, rivers and
streams, and underground as groundwater and
underground streams.
An ice cap is an ice mass that covers less
than 50,000 km² of land area (usually
covering a highland area). Masses of ice
cap that covers more than 50,000 km² are
termed an ice sheet in Antarctica and
An iceberg is a large piece of freshwater ice
that has broken off a glacier or an ice shelf
and is floating freely in open water
An ice shelf is a thick floating platform
of ic glacier or ice sheet flows down to
a coastline and onto the ocean
surface. Ice shelves are only found in
Antarctica, Greenland and Canada.

8. • The term sweet water“ has been used to
describe fresh water in contrast to salt
water

9. Freshwater biome
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Most wide spread biome 20% of earth
A biome is a regional or global community of organism. Biome are
climatically and geographically defined as contiguous areas with similar climatic
conditions on the Earth, such as communities of plants, animals, and soil
organisms, and are often referred to as ecosystems.
Fresh water biome consist of Rivers, Ponds,
lakes, streams, wetlands and marshes,
ground water and aquifers.

10. Different Types Of water Biomes
Wetlands : For regulatory purposes under the
Clean Water Act, the term wetlands means
those areas that are inundated or
saturated by surface or ground water at a
frequency and duration sufficient to support,
and that under normal circumstances do
support, a prevalence of vegetation typically
adapted for life in saturated soil conditions.
Wetlands generally include swamps, marshes,
bogs and similar areas.

11. Wetlands
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Wetlands : areas of non-moving water that
maintain Aquatic plants, marshes, swamps, and
bogs are all consider wet lands.
Plant life has adapted to the very moist and
hum i d c ond i ti ons c al l e d hyd rop hyte s,
Hydrophytes are plant that grows only in water or
very moist soil, these Include pond lilies, cattails,
sedges, tamarack, and black spruce.
Marsh plant also Include species such as cypress
and gum. Wet lands are known to have the
highest diversity of species out of all the
ecosystems.

12. Lakes and Ponds
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Size: The Regions of lakes and ponds can reach
the size of a few square meters to a thousand
square kilometers.
Age: These regions are scattered all around planet
Earth. Many ponds are seasonal only lasting a
couple of months before they dry up. Lakes can
last for hundreds of years maybe more.
Diversity: Depending On the pond or lake they may
have limited species diversity, since they are
mostly isolated from water sources such as rivers
and oceans.
Lakes and ponds are divided into different zones,
which are determined by the depth and distance

13. Lakes and ponds
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What’s the difference?
Ponds typically smaller
May be seasonal—that is, dry up part of the
year
Lakes exist hundreds or thousands of years
But, even lakes can fill in or dry up

14. Stream and River
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Stream and River are bodies of water that flow in one
direction. Streams and rivers can be found everywhere
around the world.
They get started at the headwaters or starting point,
which can be from springs, melting of snow, or waters
from a lake. This flowing waters travel to the mouth of
the river or stream, that moves to another water
channel or the ocean.
During the journey that water flow to the river or
stream changes occurs during the journey to the
source of the mouth.
The water temperatures are cooler at the main source
then at the mouth; the water is also clearer and has
higher oxygen content.
Source: where river
starts
Mouth: where it ends

15. Rivers from start to finish
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Source = Headwaters
Can be:
Snowmelt
Spring
Even a lake
Water is colder, clearer,
more highly oxygenated
Organisms include trout,
mayflies
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Mouth: where the river
ends
Usually the ocean or
another river, or lake
River widens and slows,
getting warmer, siltier.
Middle is most diverse,
lots of plants
Near mouth, increased
sediment limits light and
plants, water is warmest

16. Difference between a river and
stream
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A River and a Stream are both fast moving
bodies of water, but a river is called a River
because it is larger, deeper, and longer
than a stream. Stream is much smaller
than a river not as deep, some you can
even walk across.
Another difference is that a stream is a
small flowing water. And a river is a
collection of many streams.

17. Aquifer
An aquifer is an underground layer of
water-bearing permeable rock or
unconsolidated materials (gravel, sand, or
silt) from which
groundwater can be extracted .
The water table is the surface where the water
pressure head is equal to the atmospheric
pressure (where gauge pressure = 0). It may be
conveniently visualized as the surface of the
subsurface materials that are saturated with
groundwater in a given vicinity. However, saturated
conditions may extend above the water table as
surface tension holds water in some pores below
atmospheric pressure.

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The aquifer of Lahore is quickly depleting and
during the last three decades
it registered decline of over 300 percent which
poses serious threat about availability of water to
the City in the future.
In 2010, aquifer level in Lahore reached the
minimum 21.55 meter and maximum 43.90 meter,
registering a total decline of 15.85 meter and
24.07 meter respectively in just three decades.
At present, 460 tube wells are in operation to
supply water. The tube wells belonging to Pakistan
Railways, M.E.S., Cantonment Board, DHA,
Hospitals, PHA, government buildings, private
societies and industry and for irrigation purposes
are also extracting water from the aquifer of
Lahore.

19. Aquitard
An aquitard is a geographic
material that has ground
water. It however, cannot
lead the water through to the
surface because of low
permeability mostly caused.

20. Threats to Freshwater biome
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Threats to lakes and ponds are Biochemical waste
that is harmful to the biome.
Throwing plastics or any litter can damage the
Biome. The water gets dirty from all this waste
which is bad for any species that live there which
can cause extinction which can mess up the
balance of the food chain causing major havoc to
any living thing in that biome.
The solution to this problem is to make sure we
dispose any chemical waste properly and don’t
pour anything down the drain. We are to make sure
that we put anything wasteful in the trash and make
sure that the water is clean.

21. Where is the fresh water biome
located in the world

22. Freshwater Location
• Freshwater can be found all over the world.

23. Features of freshwater biomes
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FWB is world's most imp biome not only
because of environment and biological
factors but also b/c of climate and
geographic features.
Temperature variation, Littoral 19-25 o C,
middle 8-19 o C and bottom 4-8 o C.

24. Climate in the Freshwater biome
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It Depends on the location of the biome
During the winter times the water would
start to freeze at below zero temperature
causing ice on the surface which animal life
moves allot more slow do to low levels of
oxygen.
Around the spring the ice would melt
making the oxygen levels high again for fish
and other plant life such as algae.
In the summer high temperature, low DO,
high productivity.

25. Source of H2O in Fresh Water biome
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Precipitation, mist, acidic rains (Scandinavia,
Scotland, Wales, USA).
Fresh water has low salts and TDS.
Exclude sea water and brackish water.
Coastal areas fresh water has salts derived
from sea.
Contamination---contamination by insoluble
solids and soluble components of soils. In
Deserts wind picks up sand and dust and
deposit it elsewhere in precipitation.
Example: Significant Fe is transported: Brazil Fe
rich rain derived from sand storm in SAHARA in

26. Fresh Water biome-Types
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Lentic system (Still water, ponds, lakes)
Lotic system (Running water, ground water
which flows in aquifers)
Lentic
Lotic

27. Distribution of freshwater on earth
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2.75% water is fresh on earth
2.05% frozen in glaciers
0.68% is ground water
0.01% surface water in Lakes and rivers
(Lake Baikal and Great Lakes contain 78% )
Atmosphere 0.04% ( Variable area to area)