Morphometry, Water Movement, Planktons and Pheriphyton of Fresh Water

Morphometry

The measuring of the physical dimension of the lake is known as the morphometry. This helps for the estimation of biophysical and the chemical properties of the lake. Different types of the morphometry are as follows:

1: Maximum length (l):

The distance on the lake surface between the most two distance points on the lake shore.

2: Maximum width (b):

The maximum distance on the lake at a right angle to the line of the maximum length of the shore.

3: Area (A):

This area includes the lake area (A) and the total lake area (At).

I: Lake area (A):

It is the area of the surface of the lake.

II: Total lake area (At):

The area of the surface of the lake and the area of island inlet and the rocks within the limits of the shore.

4: Maximum depth (d):

It is the greatest depth from the surface of the lake.

5: Maximum volume (v):

The volume of the water in any lake is the integral of the area of each stratum at the successive depth from the surface to the point of the maximum depth. It can also be written as:

Volume= 1/3(A₁+A₂) +√(A₁+A₂)

Where A₁= Area of the upper surface of the lake.

A2= Area of the lower surface of the lake.

Water movement

1: Water movement in the lotic water:

The movement of water in the lotic waterbodies due to the gravitational pull, therefore, two zones are separated by these bodies viz rapid zone and the pool zone. There are also two types of the water movement in the lotic water which are turbulent flow and the laminar flow in the pool zone. In the laminar flow, all the water molecules flow parallel whereas in the turbulent flow the motion of the water molecules rein the rapid way The eroding capacity of the turbulent flow is high whereas, the deposition rate is high in the laminar flow. But in the month of the river stream, velocity suddenly checked and only vertical deposition occurs.

2: Water movement in the lentic water:

In the lentic water bodies, the water movement occurs due to the wind action i.e depends on the exposed surface area, heat, and the thermal gravity. In the shallow lakes, water circulation is more common in the epilimnion i.e upper layer but in the deeper lake internal gravity i.e rotation of earth cause as the water movement from the bottom to the surface. The movement of the water is important in the lentic water to circulate the bottom deposition nutrients upward.

Plankton of fresh water

Planktons are the floating organism whose movement more or less depends on the water current. The plant planktons are phytoplankton and the animal planktons are the zooplanktons. The phytoplanktons can be divided into the two groups on the basis of their sizes. The net planktons are retained by the silk of a plankton net: the nanoplankton includes the tiny algae not captured by the net. The number 20 mesh net is the very popular size. Among the freshwater ecosystem, planktons have the high importance in the lentic ecosystem rather than the lotic ecosystem as there is a great number of the various planktons in the lentic bodies. Lotic bodies contain the very few number or the no number of the planktons.

Phytoplankton in the littoral zones are mainly the algae, green algae, diatoms and the blue-green algae. Zooplankton in the littoral zone is the cladoceran i.e water flesh such as Daphnia, Microcephalus and some of the other species of the Copepods of the family Cyclopoidea, all of the Harpacticoidea, many Ostracods, and some other rotifers. The limnetic zone contains the phytoplanktonic algae which are found in the littoral zone. Besides, there are the algae like green flagellates, chiefly the dinoflagellates, Euglena and the Volvo cnidae. The zooplanktons are represented a few species but they are large in number n number. Copepods such as species of the diatoms, Cladocerans such as species of the Diaphanosoma, Sida, Bosnia and rotifers such as the species of the Aspatancha and the Not holes are present. No more planktons are found in the profundal zone as well as in the lotic bodies. The plankton cannot withstand the pounding of the rapid and they are restricted to the pools as they are floating organism.

Periphyton

This periphyton a word used originally to describe the organisms attached to the artificially submerged objects i.e on the plant stems, leaves and the perhaps submerged sticks. It includes both the flora and the fauna. A film of the diatoms attached by the gelatinous stalks accounts for this. Periphyton assemblages on the epilithic organism can hardly be distinguished from the macrobenthic assemblages unless the strict sessile nature of the organism is observed. Epipelic, Epiphytic, and the Epizoic periphyton organism are attached on the sediment surfaces on the plant leaves and the stems and on the animals respectively. A unique community of such epizoic periphyton organism is attached on the sediment surfaces, on the plant leaves and the stems and on the animals respectively. A unique community of such epizoic periphyton as the green alga Basicladia and a group of the suctorian ciliates make up the major part of this movables aufwuchs.

Studying the role of the attached algae in the lacustrine productivity Wetzel in 1964 discussed the confusing history of the terminology referring to these forms. Now it can be discussed under the epizoic, epiphytic, epilithic the epipelic periphyton as four kinds of aufwuchs.

The production of the both the primary and secondary periphyton has been estimated in the various ways. A common technique is based on the submerging rocks of the glass plates i.e microscope slides are often used for a long period of time and measuring the organic matter that occurs.

References:

Miller, Jr. G.T. Living in the Environment. Wadsworth Publication, 2003.

S.C., Santee. Environmental Science. India, New Center: New Center Book Agency (P) Ltd, 2004.