fresh water ecosystem

1. A
PRESENTATION
ON
FRESHWATER ECOSYSTEM
Prepared by
Abhishek- 2014bpln022
Prakash Nagesh- 2014bpln023
Gaurav kushwaha-2014bpln028
Pushpender Satyarthi-2014bpln030
Yash Songara- 2014bpln034
Peeysh Kumar Shishodia-2014bpln037

2. CONTENTS
1. What are fresh water ecosystems
2. Type of fresh water Habitats
3. Lentic Ecosystems
4. Lotic Ecosystems
5. Freshwater Wetlands
6. Forest Wetlands
7. Tidal Freshwater Marshes
8. Conclusion

3. What are the Freshwater Ecosystems
 Freshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes
and ponds, rivers, streams and springs, and wetlands
• Occupy relatively a small portion of the surface of earth compared with marine or
terrestrial ecosystems.
• They are most important as being used for the various purposes.
• They are called bottleneck of hydrological cycle.
• They provide a natural waste disposal system.
pond lake

5. TYPES OF FRESHWATER HABITATS
Lentic
Standing Water or
lentic( calm)
ecosystems : lakes
and ponds
Lotic
Running water or
lotic (washed)
ecosystems :
springs, streams
and rivers
Wetlands
Wetlands where
water level
fluctuates up and
down, often
seasonally as well
as annually :
marshes and
swamps
Ground water although a
large freshwater habitat
reservoir but it does
contain life that’s why it
is not considered as
ecosystem

6. To study the environment of lentic ecosystems it is being divided into zones
Lentic Ecosystems
Contained rooted
vegetation along
the shore
Open water
dominated by
plankton
A deep water zone
containing only
heterotrophs
Life forms in a ponds include plankton, nekton, benthos, neuston, periphyton (hydras)

7. Lentic Ecosystems

8. Lentic Ecosystems
In temperate regions, lakes often become thermally stratified during summer and again in winter
During spring and fall,
the entire body of
water approaches the
same temperature,
mixing occurs, occurs.
Blooms of
phytoplankton's often
follow these turnovers,
as nutrients from the
bottom become
available in the photic
zone.
Photic zone is the
lighted portion of a lake
inhabited by
phytoplankton

9. Lentic Ecosystems
Lakes are often classified as either oligotrophic or eutrophic on the basis of productivity
Eutrophic lake has
high nutrients
contents the high
contents of
nutrients causes
lake to go in
process which
known as
eutrophication of
lake.

10. Lentic Ecosystems
Diagram
showing
eutrophication
of lake

11. Lentic Ecosystems
IMPOUNDEMENTS
Humans have changed the landscape in regions
that lack natural bodies of water
In US almost every farm have now includes at
least one farm pond, and large impoundments
have been constructed partially on every river.
The heat budget of impoundments may differ greatly from that of natural lakes, depending on the
design of the dam. If water is released from the bottom- cold, nutrient-rich but oxygen poor
water is exported downstream, whereas warm water is retained in the lakes. This impoundments
becomes a heat trap and nutrient exporter, in contrast to natural lakes. This typre of discharge
affects down stream conditions

12. Lotic Ecosystems
Streams and Rivers
Difference between running and standing water generally revolve around a triad of conditions
1. Current is much more of a major
controlling and limiting factor in
streams
2. Land-water interchange is
relatively more extensive in
streams, result in a more open
ecosystems and a heterotrophic
type of community metabolism
when the size of stream is small
3. Oxygen tension is generally high
and more uniform in streams, and
there is little or no thermal or
chemical stratification , except in
large, slow-moving rivers

13. Lotic Ecosystems
In a given stretch of stream, 2 zones are generally apparent
A rapid zone has a current great enough to keep the bottom clear of silt or other loose
material, thus providing a firm substrate. This zone is occupied by specialized organisms that
become firmly attached or cling to the substrate.
A pool zone has deeper water, where the velocity of current is reduced by, so that sand and
silt settle , providing a soft bottom favorable for burrowing and swimming animals, rooted
plants, and, in large pools, plankton. In fact, the communities of pools in large rivers
resemble those of ponds
River in their upper reaches are generally eroding; they cut into substrate, so a hard bottom
predominates

14. Lotic Ecosystems
In terms of the chemical composition of the water, lotic ecosystems can be divided in 2 types
1. Hard water, with 100 or more ppm dissolved inorganic solids
2. Soft water, with less than 25 ppm dissolved solids
The water chemistry of carbonate rivers is controlled largely by rock weathering , whereas
atmospheric precipitation is the dominant factor in Cl rivers.
Humic or Black water streams, with high concentrations of dissolved organic material,
represent still another class of streams that are found in warm lowlands.
Springs holds a position of importance as study areas that is far out of proportion to their
size and number .

15. Freshwater Wetlands
Definition It is
defined as an area
covered by shallow
freshwater for at
least part of the
annual cycle.:
accordingly,
wetland soils are
saturated with
water continually or
part of the year .
The key factor that
determines the
productivity and
species composition
of the wetland
community is the
hydro period
River Wetlands
Located in low lying
depression(oxbows)
and flood plains
associated with
rivers. The bottom
land hardwood
forests on the flood
plains of large rivers
are among the most
productive of natural
ecosystems
Lacustrine
Wetlands
Associated with
lakes, ponds or
dammed river
channels. They are
periodically flooded
When these deeper
bodies of water
overflow
Palustrine Wetlands
Include marshes,
bogs, fens, wet
prairies . Occur in
depressions not
directly connected
with lakes or rivers .
Fens are slightly
acidic, bogs are very
acidic as they contain
peat

16. Wetland occupy only about 2 % of the surface of the earth. They are
estimated to contain 10 to 14 % of the carbon. Wetland soil histosol may
contain 20 % carbon by weight. Peats are even more carboniferous.
Draining of wetland releases large quantities of CO2 .
Freshwater Wetlands
Bog
In the last century public attitude towards wetland changed dramatically as
ecological and economic studies revealed previously unrecognized values

17. Freshwater Wetlands
Rice culture is one of the most productive
and dependable of agricultural systems yet
devised by humans it is a freshwater marsh
ecosystem. The flooding, draining and
careful rebuilding of the rice paddy each
year of the rice plant.
The flooding process is similar to the
hyperiod ( duration, frequency and depth)
of natural wetlands.

18. Forested Wetlands
Swamp and floodplains occur in river bottoms, often intermixed with marshes especially
where large rivers cross coastal plains. They are also found in large depressions, lime sinks
and other low-lying areas that are flooded at least some of the time. As with marshes,
hydrology plays a major role in determining species composition and productivity.
Bald cypress
The knees of bald cypress trees conduct air from atmosphere to roots when a swamp is flooded and
the water logged sediments contain little or fee oxygen. The greatest productivity occurs where the
soil surface is flooded in winter or spring and is relatively dry during most of the growing season
Water Tupelo

19. A tidal marsh is a type of marsh that is found along coasts and estuaries of which the
flooding characteristics are determined by the tidal movement of the adjacent estuary, sea
or ocean. According to the salinity of the flooding water, freshwater, brackish and
saline tidal marshes are distinguished. In low lying coastal plains, tides extend inland on
large rivers.
For example-meter amplitude tide occurs on the Potomac river beyond Washington DC and on the
James River as far inland as Richmond, Virginia, creating a unique habitat of freshwater wetland.
Fleshy, low –fiber vegetation is produced in fresh water tidal marshes summer, which then
decomposes back to mud in winter, in contrast to salt marshes where the more fibrous
marsh grass remain standing all year around
Potomac river marshes
Tidal Freshwater Marshes

20. 1. Freshwater Ecosystems are very important part of our earth ecosystem as they provide
the water for various purposes and use.
2. They also help the domesticated and Terrestrial ecosystem to survive and keep these
kind of ecosystem alive in nature.
3. Ecosystem of Freshwater are very less on our earth
4. They just occupy 1 %total water present on earth which supports the more than 7
billion human population and thousand of species present on our earth.
5. So it is important to keep fresh water ecosystem safe from other system as it is a life for
other ecosystem.
Conclusion