6
resting stages, once a year, it is monocyclic ; if
twice, dicyclic , etc. If no changes occur, it is
acyclic .
Thus, in the present chapter, an elaborate discussion of the various terminologies regarding
the biota of wetlands and lakes has been done.
1.7
Essential Nature, Objectives
and Scope of Limnological
Study
Limnology, primarily, is ecological in its bearing. It is essentially a synthetic science composed of elements, some of which extend well
beyond the limits of biology. Limnology relies
on proper application and integration of certain
principles and methodologies of physics, chemistry, geology, geography, meteorology, hydrography, etc. for the solution of problems, which
are, ultimately, biological in nature. As such, in
order to qualify it as a science, limnology must
possess certain central unifying features which
tie the whole subject into a coherent orderly
organised fi eld.
Further, limnology is directed to the analysis
of the modus operandi of the complex web of climatic, physical, chemical and biological factors
in all natural aquatic systems in collaboration
with all disciplines of natural science which are
relevant to the overall picture. For example, geology and meteorology are related to the historical
and climatic; physics and physical chemistry are
relevant to the mechanics and composition of
water; biochemistry and molecular biology are
linked with the material transformation occurring
in the water body. These gave rise to various
research pathways within limnology, like limnochemistry, limnophysics, limnobotany, limnozoology, limnobacteriology and hydrobiology. In
short, the task of limnology is to investigate and
explain the system properties of natural waters.
This provides with the basis of more down-toearth discipline of applied limnology which bears
the responsibility of furnishing with answers to
those problems of freshwater management which
are created by overpopulation and urbanisation
along with environmental protection. Aspects of
sewage treatment, pollution of natural waters,
water quality conservation and restriction are
some of the concerns of applied limnology.
Further areas of application are the fi shery
biology including efforts designed to increase
rate of organic production in natural and artifi cial
waters and hence to remedy the protein differences affecting human nutrition, especially in the
developing countries. Many nations have introduced intensively managed algal growth projects,
particularly, fertilised by the sewage effl uent and
have achieved a high level of protein production.
Nevertheless, the main aim of modern limnology is to understand the natural circumstances
responsible for the tremendous differences in
natural waters and to identify and evaluate the
infl uences which govern a particular form of productivity, in view of the fact that inland waters
display great diversity in the quality and quantity
of life which they contain. Modern limnology
also deals with its relationship with other
branches of science ( Kar 2007a ).
1.8
Present Status of Limnology
Studies in limnology today comprehend three
major areas, namely, physics, chemistry and biology. The physical aspects include studies related
to physiography, morphology, bathymetry, fl uvial dynamics, transparency and thermal profi le,
etc. Chemical area encompasses determinations
and estimations of parameters like pH, dissolved
oxygen (DO), free carbon dioxide (FCO 2 ), total
alkalinity (TA) and total hardness (TH) and the
nutrients like phosphate and nitrate and trace elements like Mn, Mg, Pb, Hg, As, Cd, B and Cu.
The biological components in limnological study
deal with in-depth discourses on the living beings
notably the plankton, the nekton and the benthos
covering both plants and animals ranging from
micro- to macro-level.
Discovery of microscope paved the way for
great stimulus to aquatic investigations through
the discovery of plankton. Although the knowledge of microscopic biota in water could be
traced back to Leeuwenhoek, the discovery of
‘plankton’ (the heterogeneous group of suspended
1 Introduction
resting stages, once a year, it is monocyclic ; if
twice, dicyclic , etc. If no changes occur, it is
acyclic .
Thus, in the present chapter, an elaborate discussion of the various terminologies regarding
the biota of wetlands and lakes has been done.
1.7
Essential Nature, Objectives
and Scope of Limnological
Study
Limnology, primarily, is ecological in its bearing. It is essentially a synthetic science composed of elements, some of which extend well
beyond the limits of biology. Limnology relies
on proper application and integration of certain
principles and methodologies of physics, chemistry, geology, geography, meteorology, hydrography, etc. for the solution of problems, which
are, ultimately, biological in nature. As such, in
order to qualify it as a science, limnology must
possess certain central unifying features which
tie the whole subject into a coherent orderly
organised fi eld.
Further, limnology is directed to the analysis
of the modus operandi of the complex web of climatic, physical, chemical and biological factors
in all natural aquatic systems in collaboration
with all disciplines of natural science which are
relevant to the overall picture. For example, geology and meteorology are related to the historical
and climatic; physics and physical chemistry are
relevant to the mechanics and composition of
water; biochemistry and molecular biology are
linked with the material transformation occurring
in the water body. These gave rise to various
research pathways within limnology, like limnochemistry, limnophysics, limnobotany, limnozoology, limnobacteriology and hydrobiology. In
short, the task of limnology is to investigate and
explain the system properties of natural waters.
This provides with the basis of more down-toearth discipline of applied limnology which bears
the responsibility of furnishing with answers to
those problems of freshwater management which
are created by overpopulation and urbanisation
along with environmental protection. Aspects of
sewage treatment, pollution of natural waters,
water quality conservation and restriction are
some of the concerns of applied limnology.
Further areas of application are the fi shery
biology including efforts designed to increase
rate of organic production in natural and artifi cial
waters and hence to remedy the protein differences affecting human nutrition, especially in the
developing countries. Many nations have introduced intensively managed algal growth projects,
particularly, fertilised by the sewage effl uent and
have achieved a high level of protein production.
Nevertheless, the main aim of modern limnology is to understand the natural circumstances
responsible for the tremendous differences in
natural waters and to identify and evaluate the
infl uences which govern a particular form of productivity, in view of the fact that inland waters
display great diversity in the quality and quantity
of life which they contain. Modern limnology
also deals with its relationship with other
branches of science ( Kar 2007a ).
1.8
Present Status of Limnology
Studies in limnology today comprehend three
major areas, namely, physics, chemistry and biology. The physical aspects include studies related
to physiography, morphology, bathymetry, fl uvial dynamics, transparency and thermal profi le,
etc. Chemical area encompasses determinations
and estimations of parameters like pH, dissolved
oxygen (DO), free carbon dioxide (FCO 2 ), total
alkalinity (TA) and total hardness (TH) and the
nutrients like phosphate and nitrate and trace elements like Mn, Mg, Pb, Hg, As, Cd, B and Cu.
The biological components in limnological study
deal with in-depth discourses on the living beings
notably the plankton, the nekton and the benthos
covering both plants and animals ranging from
micro- to macro-level.
Discovery of microscope paved the way for
great stimulus to aquatic investigations through
the discovery of plankton. Although the knowledge of microscopic biota in water could be
traced back to Leeuwenhoek, the discovery of
‘plankton’ (the heterogeneous group of suspended
1 Introduction