short PPT on Fresh Water Biology

1. By
KETAN MAKDE
FRESH WATER
BIOLOGY

2. Oxygen deficit, D = Saturation DO – Actual DO
The saturation DO value for fresh water depends upon the temperature and total dissolved
salts present in it; and its value varies from 14.62 mg/L at 00C to 7.63 mg/L at 300C, and
lower DO at higher temperatures.
OXYGEN SAG ANALYSIS
The oxygen sag or oxygen deficit in the stream at any point of time during self purification
process is the difference between the saturation DO content and actual DO content at that time.

6. The rate of reoxygenation depends upon:
i) Depth of water in the stream: more for shallow depth.
ii) Velocity of flow in the stream: less for stagnant water.
iii) Oxygen deficit below saturation DO: since solubility rate depends on difference between
saturation concentration and existing concentration of DO.
iv) Temperature of water: solubility of oxygen is lower at higher temperature and also saturation
concentration is less at higher temperature.

7. Eutrophication of Water Bodies

8. Tropic Level and Status

14. Nitrogen
Atmospheric nitrogen (N2) isn’t usable by
plants
Most blue-green algae can “fix”
atmospheric nitrogen
Ammonia (NH4) is formed as a product of
decomposition
NH4 and NO3 are both used by algae
Sources include: fertilizer, sewage waste,
animal waste, atmosphere
Phosphorus
 No atmospheric gaseous phase
 Sources: fertilizer, animal and human
wastes, detergents, natural rocks
 Found in runoff and precipitation
 Is the primary plant nutrient of algae

15.  Lawn Fertilizer
29-3-4 on label means
29 parts N : 3 parts P : 4 parts K
 Most lawns have plenty of available phosphorus!
 Phosphorus-free lawn fertilizers are becoming widely
available.
Process of excessive addition of:
Inorganic nutrients
Organic matter, and
Silt
to lakes leading to increased biological
production and a decrease in lake volume.

23. Rivers and their associated floodplains support a wide range of native
flora and fauna, many of which are now rare or threatened. The distribution,
abundance and health of these species and communities are closely associated
with the condition of the riverine environment.
The Victorian River Health Strategy defines a river, stream or natural waterway
as including:
·The channel
·The riparian zone, which includes the area of land that adjoins, regularly
influences, or is influenced by the river.
·The regularly wetted floodplain and any associated floodplain wetlands.
·The estuary or terminal lake.
Flora and fauna in river

24. Flora is the plant life occurring in a particular region or time, generally the naturally
occurring or indigenous—native plantlife. The corresponding term for animal life
is fauna. Flora, fauna and other forms of life such as fungi are collectively referred to
as biota. Sometimes bacteria and fungi are also referred to as flora, as in the terms gut
flora or skin flora.
Flora

25. Fauna is all of the animal life of any particular region or time. The
corresponding term for plants is flora. Flora, fauna and other forms of life such
as fungi are collectively referred to
as biota. Zoologists and paleontologists use fauna to refer to a typical collection
of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or
the "Burgess Shalefauna". Paleontologists sometimes refer to a sequence
of faunal stages, which is a series of rocks all containing similar fossils. The
study of animals of a particular region is called faunistics.
Fauna

28. LIMNOLOGY
 Limnology is the science dealing with the physical, chemical, biological and
meteorological study of inland waters.
 is the study of inland waters
 It covers the biological, chemical, physical, geological, and other attributes of all inland
waters (running and standing waters, both fresh and saline, natural or man-made).
 This includes the study of lakes and ponds, rivers, springs, streams and wetlands.
 Limnology is closely related to aquatic ecology and hydrobiology, which study aquatic
organisms in particular regard to their hydrological environment. Although limnology is
sometimes equated with freshwater science, this is erroneous since limnology also
comprises the study of inland salt lakes.

29. Glaciated
Lake
Reservoir Oxbow
Lake Types

30. Lake Communities

31. Three basic types of freshwater ecosystems:
• Lotic: rapidly-moving water, for example streams and rivers.
• Lentic: slow-moving water, including pools, ponds, and lakes.
• Wetlands: areas where the soil is saturated or inundated for at least part
of the time.

32. Nutrients and Lakes:
 Oligotrophic:
 Low nutrient availability
 Low surface area to volume ratio
 Low biological production
 well oxygenated
 May have high species diversity
 Generally older lakes
 Eutrophic:
• High biological production
• High nutrient availability – particularly N and K
• High surface area to volume ratio
• may be depleted of oxygen – benthos anaerobic  methane
production
 Dystrophic:
• Acidic, high in organic matter