FRESHWATER ECOLOGY
is the study of a freshwater ecosystem or also termed as Limnology is a specialized subcategory of the overall study of organisms and the environment.Freshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes and ponds, rivers, streams and springs, and wetlands
FRESHWATER ECOLOGY
Freshwater habitats can be classified by different factors, including temperature, light penetration, transparency, etc. Freshwater ecosystems can be divided into lentic ecosystems and lotic ecosystems.
TYPES OF FRESHWATER HABITAT
I. Lentic habitat Calm freshwater habitat or standing water refers to standing or relatively still water, from the
Latin lentus, which means sluggish.II. Lotic Habitat
Washed or the running water refers to flowing water, from the Latin lotus, to
wash
Lentic Habitat
a. Lakes - is a body of relatively still fresh water of considerable size, localized in a basin, that is surrounded by land.
Lentic Habitat
b. Ponds- body of standing water, either natural or man-made, that is usually smaller than a lake.
Lentic Habitat
c. Swamp - is a wetland that is forested
Lentic Habitat
d. Bog - is a wetland that accumulates peat, a deposit of dead plant material—often mosses, and in a majority of cases, Sphagnum moss.
Lotic Habitat
a. Spring – kind of freshwater habitat where water flows out of the ground
Lotic Habitat
b. River - is a body of water with current moving in one general direction.
Lotic Habitat
c. Stream - a thin body of water which has a continuous flow of water, often referred to as a creek or a brook.
LIMITING FACTORS
I. Temperature Water thermal properties combine to minimize
temperature changeII. Current
Current direction is a very important limiting factors
Largely determine the distribution if vital gases, salts and small organisms
LIMITING FACTORS
III. Transparency Turbidity, especially when caused by clay and slit
particles Can be measured using an instrument called a
Secchi disk
LIMITING FACTORS
IV. Concentration of respiratory gases Oxygen and carbon dioxide concentration are often
limiting in the fresh water environmentV. Concentration of biogenic salts
Nitrates and phosphates seem to be limiting in a freshwater ecosystem
Calcium and other salts are likely to be limiting in soft water lakes and streams
MAJOR GROUPS OF FRESHWATER ORGANISMS
Classified into:1. Major niches (based on their position in the
energy level or food chain)a. Autotrophs (producers)b. Phagotrophs (Macroconsumers)c. Saphotrophs (microconsumers/decomposers)
MAJOR GROUPS OF FRESHWATER ORGANISMS
Classified Into:2. Life Form Of Habitat (Based On Their Mode Of
Life)a. Benthos – Resting Or Living In The Bottom Of
Sediments. Ex. Clams And Snailb. Periphyton – Organisms Living On The Stems And
Leaves Of Rooted Plants. Ex. algae, cyanobacteria
MAJOR GROUPS OF FRESHWATER ORGANISMS
Classified into:2. Life form of habitat (based on their mode of
life)c. Plankton – floating organisms whose movements
depend on the current.d. Nekton – swimming organisms able to navigate at
will. Ex. Fishese. Neuston – organisms resting or swimming on the
surface. Ex. protozoans, bacteria
MAJOR GROUPS OF FRESHWATER ORGANISMS
Classified into:3. Region or subhabitat
…. In lakea. Littoral zone – shallow water region with light
penetration to the bottom. b. Limnetic zone – open water zone to the depth of
effective light penetration which photosynthesis balances respiration.
c. Profundal zone – bottom and deep water area.
MAJOR GROUPS OF FRESHWATER ORGANISMS
Zones of a lake
MAJOR GROUPS OF FRESHWATER ORGANISMS
Classified into:3. Region or Subhabitat
….in streamsa. Rapid zone – shallow water where velocity of
current is great enoughb. Pool zone – deeper water where velocity of current
is reduced.
THANK YOU FOR LISTENING