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INTRODUCTION
Water is the basic and primary need of all vital life process. It is an essential and the
most abundant substance in protoplasm of all living organism (Tripathi and Pandey,
1990).Water is described as the living organism. Water is described as the mother of life and
in the liquid gold. It form’s the principle external as well as internal medium of an aquatic
habitat. Water is largest medium for life of organism. Water cover’s about 71% of the earth
surface and constitutes about 70-90% of protoplasm and is most essential for almost all the
metabolic and chemical reactions. Freshwater makes up only 26% water also acts as a major
controlling factor of the organism.
Water is not only essential to life but is Predominate inorganic constituent of living
matter forming nearly three quarters of the weight of a living cell. In living tissue water is the
medium for many biological reactions and extraction processor of inorganic nutrients
photosynthetic ingredients and minerals etc. are transported in aqueous medium. In short
water is essential for life and plays a unique role virtually as medium in all biological
process.
Water quality includes all physical, chemical and biological factors that influence the
beneficial use of water. Physico-chemical analysis is the prime consideration to assess the
quality of water for its best utilization like drinking, irrigation, fisheries, industrial purpose
etc. and helpful in understanding the complex processes, interaction between the climatic and
biological processes in the water.
Water maintained by several physicochemical factors and any decrease or increase
cause the death of organisms as cited by Pritchard et al., (2008). Water quality and the risk to
waterborne diseases are critical public health concerns in many developing countries today.
The increasing anthropogenic pressure influences in recent years in and around aquatic
systems and their catchment areas have contributed to a large extent to deterioration of water
quality and dwindling of water bodies leading to their accelerated eutrophication as reported
by Bhatt et al., (2004). Good quality of water is essential for living organisms. The quality of
water can be assessed by studying its physical and chemical characteristics as well as by
plankton growing in it. Because of vast population and negligence of human being the quality
of water is being deteriorated day by day. The limnology plays an important role in decision
making process for problems like dam construction, pollution control, fish and aqua culture
practice. Changes in the water quality affect the biotic community of the aquatic ecosystem
which ultimately reduces the primary productivity as per Rossiter et al., (2010).
River are the major sources of drinking water, besides their usages in agriculture,
washing, bathing etc. Water is essential element of life for growth and vital activities of
human beings on the earth. Only small amount of water that occurs in fresh water rivers,
streams, lakes and tanks is available for the terrestrial life. The river Narmada is the third
holy and fifth longest west flowing river of India and the biggest west flowing river of the
state of Madhya Pradesh (Mukati et al., 2014). It is obvious that water is a poor thermal
conductor and slight variation in temperature result in rapid change in its density. The surface
tension and viscosity of water play a significant impact in shaping the characteristics of
concerned planktonic communities and other micro-organism. The interaction between
physical and chemical factor’s of any aquatic ecosystem determines the nature of aquatic
fauna and flora inhabiting it. The temperature and day length are the most important factors
to determine seasonality. According to Welch (1952) in 20th century, the progress of
Limnology is rapid as a result of which it has become an integrated and coherent branch of
Biology.
River Narmada is the most important river system of the state of Madhya Pradesh.
Besides being a very important source of water. The Narmada basin lies between east
longitudes 72o32’ to 81o45’ and north latitudes 21o20’ to 28o45’. Narmada River is a lotic
water resource. It is the only non snow fed perennial river in India. Narmada River water is
mainly used for irrigation, drinking, fishery, electricity generation and domestic purpose. Few
of the physico-chemical parameters are studied to assess the quality of water. Pollution is the
biggest problem now a days. Besides our atmosphere soil and all water resources are affected
by pollution.
The increasing rate of human population and industriallization have created problems
of domestic and Industrial effluents which are discharged into nearby river’s reservoirs and
even adjoining fields.
The investigation of hydrobiological characteristics of inland water bodies is
absolutely necessary and provides proper and complete spectrum to develop it, which can
play an important role in the economy of every country of the world. The biotic flourishing in
freshwater are influenced by a large number of physical and chemical factor’s such as
temperature, turbidity, transparency, pH, hardness, dissolved O2, BOD, COD, total alkalinity
etc. Which are interlinked between it self.
Limnology is a “Science of freshwater system or aquatic ecology comprising inter
disciplinary science including hydrobiology, hydrophysics and geology” (Golterman 1975).
Odum (1971) studies on freshwater habitat with special reference to its physico-chemical,
geological and biological characteristics is termed as limnology. The study of functional
relationship and productivity of freshwater, biotic communities as they are affected by the
dynamics of physical, chemical and biotic environmental parameters (Wetzel, 2001).
Existing physico-chemical characteristics of the water are conductive to life of
organism. Temperature, dept, turbidity and light constitute the more important physical
parameter on which the planktonic community of river depends. Fluctuations in this
constitution often creates on adverse environment to organism limiting their planktonic
community. The role of planktonic organism in aquatic environment is an essential link in the
food chain and they are capable of affecting the entire aquatic biota.
The study of freshwater habitats is known as limnology. Freshwater habitats can be
further divided into two groups as lentic and lotic ecosystems based on the difference in the
water residence time and the flow velocity. The term lotic (from lavo, meaning ‘to wash')
represents running water, where the entire body of water moves in a definite direction. These
may comprise brooks, streams, rivers and springs. Brook is a term used for the small body of
water while river is a term used for a relatively large natural body of water. The stream is
generally designated as smaller than a river but bigger than a brook. Spring is an issue of
water from the earth, which takes the form of a stream on the surface (Kalff, 2002; Wetzel,
2001).
TROPHIC INTERACTIONS IN AQUATIC FOOD CHAIN
In most aquatic food chains, the community interactions are often controlled by
abiotic factors or predation at higher levels of food chain. The control of primary production
by abiotic factors such as nutrients is called “bottom-up control”. The control of primary
production by the upper levels of food chain is referred to as “top-down control”. The idea
that predation at upper levels of food chain can have cascading effect down through the food
chain is called the “trophic cascade” (Dodds, 2002). The bottom-up hypothesis requires that
the biomass of all trophic levels is positively correlated and depend on fertility (limiting
resources) of the habitat.
MONITORING OF WATER BODIES
With the advent of industrialization and increasing populations, the range of
requirements for water has increased together with greater demands for higher water quality.
Industrialization coupled with intensive agriculture in early 1980's to meet the growing
demand of ever increasing populations, the range of requirements for water has increased
manifolds. In addition to many intentional water uses, there are several human activities,
which have indirect and undesirable, if not devastating, effects on the aquatic environment,
which include uncontrolled and unplanned land use for urbanization or deforestation,
accidental (unauthorized) release of chemical substances, discharge of untreated waste or
leaching of noxious liquids form solid waste deposits. Similarly, uncontrolled and excessive
use of fertilizers and pesticides for agricultural purposes has long-term effects on the ground
and surface water resources.
In order to protect the water resources from continuing deterioration, and to supply
higher quality water for human consumption, there is a need to assess the quality of water.
The main reason for assessment of quality of aquatic environment has been to verify whether
the observed water quality is suitable for intended use. The overall process of evaluation of
physical, chemical and biological nature of water in relation to natural quality, human effects
and intended uses, particularly the uses which may affect human health and health of the
aquatic ecosystem itself is termed as water quality assessment (UNEP, 1996).
Plankton is a word derived from Greek for “drifters”. It refers to all the plants and
animals that drift with the ocean currents as inhabitants the open waters of the sea and also
fresh waters; but our concern here is with marine environments. Zooplanktons, the planktonic
animals, are all weak swimmers, whereas phytoplankton, planktonic plants, do not swam al
all. Plankton have traditionally been distinguished from nekton, those animals which swim
rapidly and migrate where they choose, irrespectively of the directions of the currents, e.g.
fish, squid, marine mammals, and sea turtles. In the open sea everything must float, swim, or
sink. The only physical objects that can remain near the surface without floating are living
organisms. For living plants and animals, there are only a few ways to remain near the
surface in safety. This is because in open water there is no sever, no trees or rocks beheld
behind which they can hide.
Plankton, particularly phytoplankton, has long been used as indicators of water
quality. Because of its short life span and quick responses to environmental changes the
standing crops and species composition indicate the quality of water in which it is found.
Clean water supports a great diversity of organisms, whereas, very few organisms survive in
polluted water with one or two dominant forms. Phytoplankton constitutes the basis of
nutrient cycle of an ecosystem, hence, play an important role in maintaining equilibrium
between living organisms and abiotic factors. Planktons are especially important as one of the
most sensitive components of an aquatic ecosystem that signal environmental disturbances is
formed. However, this important biodiversity in aquatic ecosystem has remained neglected.
At the base of aquatic ecosystem phytoplankton are the producers which are looked for as a
major component of any freshwater system. Phytoplankton play a key role in solving several
environmental problems, understanding aquatic ecosystem and also the production of useful
substances (Patil et al., 2013).
Planktons are very sensitive to the environment they live in any alteration in the
environment leads to the change in the plankton communities in terms of tolerance,
abundance, diversity and dominance in the habitat. Therefore, plankton population
observation may be used as a reliable tool for biomonitoring studies to assess the pollution
status of aquatic bodies (Mathivanan and Jayakumar, 1995). The study of plankton as an
index of water quality with respect to industrial, municipal and domestic pollution has been
reported earlier (Acharjee et al., 1995; Jha et al., 1997). The present investigation was carried
out on the surface plankton population in the aquatic ecosystem of Narmada river water.
Within the plankton, itself holoplankton are those organisms that spend their entire
life cycle as part of the plankton (e. g. most Algae, copepods, salps) by contrast meroplankton
are those organisms that are only planktonic for part of their lives (usually the larval stage).
Plankton abundance and distribution are strongly dependent on factors such as ambient
nutrients concentration the physical state of the water column, and the abundance of other
plankton.
Phytoplankton abundance in a fresh water body reflects the average ecological
condition and, therefore, it may be used as an indicator of water quality. In natural waters
such as lakes, rivers and swamps, the greatest amount of biological production is due to the
smallest organisms, namely the plankton. These microscopic plants comprise communities
that drift aimlessly with tides and currents, yet they incorporate and transfer large amounts of
energy that they pass on to higher trophic levels. Thus communities of plankton, as distinct
from those of swamp, forest, or grassland, support other communities of aquatic species and
man (Kumar et al., 2012).
The importance of phytoplankton is beyond question since it occupies the center of
the aquatic food chain. Primary productivity is entirely dependent on phytoplankton
population. Phytoplankton generates 70% of the world’s atmospheric oxygen (R. K. Negi,
Anjana Rajput, 2013). Phytoplankton always live near the surface of the river because, like
all plants, they require light for photosynthesis the transformation of water and carbon
dioxide into short chain sugars. Unlike terrestrial plants that must counteract gravity to reach
toward the sun, with strong trunks, branching stems and large leaves, the plants in the pelagic
zone are exceptionally small, microscopic, and single-celled, buoyantly supported by the
density of the surrounding water. Plants, of course, do not have muscle tissue and so they
cannot swim like oceanic animals. But without special adaptations of some type, these tiny
plants would necessarily eventually either sink to the bottom and die. Plants can remain near
the surface only if they are almost neutrally buoyant. Small objects weight less than large
ones. Small objects have a large surface area in relation to their volume. And since
phytoplankton are very small objects indeed, often only 1/1000th of a millimeter in diameter,
they don’t weigh very much and they have very large surface area/volume ratio. Small
objects and phytoplankton, therefore, sink slowly because they don’t weight very much and
because they have a large surface area in contact with water, which is far stickier than air.
Interestingly some of appendages, called flagella that propel the single-celled plant slowly
through the water. Because the cells sink very slowly, equally slow swimming speeds can
maintain these plants near the surface, other types of cells change their buoyancy by
manufacturing light-weight oils when they sink too deep. Since oil floats, the positively
buoyant cell now floats slowly back toward the surface.
Phytoplankton also remain near the surface because the surface of the open sea and
large lakes are regularly mixed each day by the wind. The sun brings light for photosynthesis
to the water surface but it also brings heat, and the warm surface waters float above the
denser and colder deeper water mass. The transition between these two bodies of water,
where the temperature changes abruptly, is called the thermocline. When the wind blows, it
mixes the surface waters but only down to the thermocline. There the density difference is
sufficiently strong to resist further mixing, and so the heat accumulates mostly near the
surface. The waters above the thermocline mix completely each day, from the surface to
depths of 10 to 100 meters. But single called plants sink at rates of only a few meters each
day, and so even though some kinds of phytoplankton, such as diatoms, sink inexorably
toward the bottom, they are mixed at greater distances and more rapid speeds throughout the
upper water column by the wind each day, for faster than they can ever sink.
Planktons are also often described in terms of size. Usually the following divisions are
used
Megaplankton
20 mm.
Meroplankton
2.20 mm.
Mesoplankton
0.2 to 2 mm.
Meroplankton
20 to 200 µm.
Nanoplankton
2 – 20 µm.
Picoplankton
0.2 to 2 µm
Femtoplankton
< 0.2 µm.
Plankton are of immense value as food and play an important role in the disposal of
sewage and in the natural purification of polluted waters. However some plankton, from a
harmful bloom that may cause high mortality among the aquatic organisms and pose a serious
hazard in the water supply for domestic and industrial use. Phytoplanktons (from Greek
Phyton), autotrophic, prokaryotic or Eukarotic algae that live near the water surface where
there is sufficient light to support photosynthesis. Among the more important groups are the
diatoms, cyanobacteria and dinoflagelates.
Planktons are minute organisms and is essential links in food chain in aquatic system.
Phytoplankton’s and zooplanktons are the major group of plankton. Phytoplanktons play a
phenomenal role in the biosynthesis of organic material while zooplankton forms important
components of secondary production. The zooplankton forms of link between phytoplankton
and micro invertebrates which in turn provide food to fishes and aquatic birds. Planktonic
primals in fresh water are dominated by rotifers, cladocerans and copepods. Rotifers are most
sensitive bioindicators of water quality and their presence may be used as a reference to the
physico-chemical characteristics of water.
The plankton community is a heterogeneous group of tiny plants (Phytoplankton) and
animals (zooplankton) adapted to suspension in the sea and fresh water. Their intrinsic
movements, if any are so feeble that they remain essentially at the mercy of every water
current. It is a potentially functional community of similar organizational rank implicit in the
terms ‘forest’ or ‘grassland’ communities. The zooplanktonic assemblage inhabiting fresh
water comprises protozoa, coelenterate, Rotifera, Gastrotricha, Bryozoa and Arthropoda.
Plankton can also be classified on the basis of size (capture methods). Net plankton are those
retained by a townet while nannoplankton will normally pass through. Plankton is also
distinguished as holoplankton and meroplankton: the former remain planktonic through their
life and the latter for a short period of their life, e.g. Glochidium larvae of freshwater mussels.
Plankton are sometimes referred to by their habitat. The plankton from ponds are called
heloplankton of lakes limnoplankton, of running water potamoplankton (rheoplankton) and of
salt water haliplankton. The pseudoplankton is those which occupy the upper layer of water
accidentally. Examples of these may be creeping organisms which rise up along the aquatic
vegetation and are accidentally caught in the planktonic collection.
Plankton consists of any drifting organism (Animals, Plants, archaea or bacteria) that
inhabit the pelagic zone of oceans, seas, or bodies of fresh water. They provide a crucial
source of food to aquatic life. The zooplanktons from major link in the energy transfer at
secondary level in aquatic biotopes. The occupy an intermediate position in aquatic food
webs between autotrophs and heterotrophs. The distribution and diversity of zooplankton in
aquatic ecosystems terms depends mainly on the physico-chemical proportion of water.
Pollution of water bodies by different sources will result in drastic changes in zooplankton
potential of the ecosystem. Zooplanktons are known to accumulate chemicals by direct
absorption from water and through food intake.
The study of different water parameters is very important for understanding of the
metabolic events in aquatic ecosystem. The parameters influence each other as well as they
govern the abundance and distribution of the flora and the fauna. Therefore, it has become
obligatory to analyse at least the important water parameters when ecological studies on
aquatic ecosystem are carried out. Such studies when done from time to time can indicate the
favourable or unfavourable changes occurring in the ecosystem. An ecosystem is a complex
of abiotic and biotic features operating in a very harmonious manner and thus maintaining
population and healthy communities of interacting organisms. Any extraneous influence
shifts this balance and the variations appear through either changes in abiotic or biotic
conditions or both seasonal fluctuations of various physic-chemical factors mediated due to
various factors like morfometry etc. have an important role in thy distributions, periodicity
qualitative and quantitative composition of biota in an aquatic ecosystem.
The intricate system in an aquatic environment constitutes two main aspects physicchemical and biological both the aspects are significant in monitoring the water quality, yet
the physic-chemical conditions are of primary concern. Physico-chemical parameters often
create an adverse environment to organism limiting their production and interfering subtly
with the physiological process, which reduce their obility to complete with other population
within the environment. Ideally thy quality of water should be assessed on the basis of
physic-chemical and biological parameters in order to provide the complete spectrum of
information required for the purpose of fish culture and its proper management.
Thy physico-chemical characteristic are the most influencing parameters which affect
thy life in water
fluctuations in these constituents often create an adverse environment to
organism limiting their production and interfering in the physiological process. Freshwater
environment are highly diversified and marked by a wide range of physico-chemical
condition which greatly influence the life in water.
Zooplankton communities are highly sensitive to environmental variation. As a result,
changes in their abundance, species diversity, or community composition can provide
important indications of environmental change or disturbance. Zooplankton communities
often respond quickly to environmental change because most species have short generation
times (usually days to weeks in length). Zooplankton communities respond to a wide variety
of disturbances including nutrient loading (e.g. McCauley and Kalff 1981, Dodson 1992),
acidification (e.g. Brett, 1989).
A change in the physico-chemical aspect of a water body brings about a
corresponding change in the relative composition and abundance of the organisms in that
water. Biomonitoring (biological surveillance) is the systematic use of living organisms or
their responses to determine the quality of the environment.
Aquatic ecosystem is the most diverse ecosystem in the world. The first life originated
in the water and first organisms were also aquatic where water was the principal external as
well as internal medium for organism. Limnology has come a long way since the time in
understanding the dynamic of a lentic water bodies subsequently. Limnology was studied
with reference to the organism especially plankton. Zooplanktons are important in an
environmental impact study. They are extremely responsive to change in the environment and
thus indicate environmental changes and fluctuations that may occur. Zooplankton acts as a
biological indicator of water pollution (Chandan Sharma and Rohini Prasad Tiwari, 2011).
Planktons are of immense value as food and play an important role in the disposal of
sewage and in the natural purification of polluted waters. However some plankton, from a
harmful bloom that may cause high mortality among the aquatic organisms and pose a serious
hazard in the water supply for domestic and industrial use (Hasan et al., 2010). Plankton are
organisms of relatively small size mostly microscopic , which have either relatively small
powers of locomotion or else none at all and which drift in the water subject to the action of
waves, currents and other forms of water motion. Phytoplankton mainly includes diatoms and
dianoflagellates. Plankton is of utmost importance in the freshwater ecosystem as these are
the main source of energy and having a very high nutritive value (Mishra and Joshi, 2003).
Biodiversity and conservation of freshwater ecosystems has been the focus of regional
assessments recently since along with their terrestrial counterparts, aquatic ecosystems have
been increasingly placed under pressures to provide renewable resources while being exposed
to the ravages of poor planning and pollution. Listed among the identified impacts on aquatic
biodiversity are deforestation, agriculture (including pesticides and irrigation), urban and
industrial development, river regulation for water and hydropower production, mining,
petroleum extraction, introduction of exotic species, dumping of solid wastes, dredging and
channelization, overfishing and the aquarium trade identified Trinidad and Tobago`s
freshwater ecosystems as being of local importance in terms of biological distinctiveness, but
endangered in term of conservation status. They concluded that they are a priority area for
conservation at the regional scale. The diversity of planktons in the river Narmada which are
declining at an alarming rate (Sharma et al., 2013).
All the aquatic system and their biota affect directly or indirectly human beings. All
forms of life, on the Earth depend upon water for their mere existence. Among all the
freshwater aquatic biota, zooplankton population is able to reflect the nature and potential of
any aquatic systems (Kumar et al., 2011). Zooplankton offer several advantages as indicators
of environmental quality in both lakes and rivers. As a group, they have worldwide
distribution, species composition and community structure which are sensitive to changes in
environmental conditions, nutrient enrichment and different levels of pollution (Jha and
Barat, 2003; Holz and Hoagland, 1996).
The Plankton occurs in all natural water as well as in artificial impoundment like
ponds, tanks, reservoir, irrigation channels etc. plankton are floating forms drifting into
currents. Now-a-day the distribution and composition of planktonic species are considered as
remarkable measure to study and determined the status of pollution in water. The studies of
phytoplankton are the subject of great interest because of their role as Primary producers in
an aquatic ecosystem. Zooplankton are the major mode of energy transfer between
phytoplankton and fish and important for fish population (Mahor R.K, Singh Beena, 2010).
Phytoplankton are the autotrophic component of the plankton community. The name
comes from the Greek words (phyton), meaning "plant" and (planktos), meaning "wanderer"
or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye.
However, when present in high enough numbers, they may appear as a green discoloration of
the water due to the presence of chlorophyll within their cells.
Zooplankton
The zooplanktons from major link in the energy transfer at secondary level in aquatic
biotopes. The occupy an intermediate position in aquatic food webs between autotrophs and
heterotrophs. The distribution and diversity of zooplankton in aquatic ecosystems terms
depends mainly on the physico-chemical proportion of water. Pollution of water bodies by
different sources will result in drastic changes in zooplankton potential of the ecosystem.
Zooplanktons are known to accumulate chemicals by direct absorption from water and
through food intake.
The grazing rate of zooplankton is one of the major factors influencing the size of the
standing crop of phytoplankton, and thereby the rate of production. A sharp decline in the
number of diatoms following their spring outburst has been found to occur before the
nutrients are fully exhausted. This is correlated with the increase in quantity of zooplankton,
and so grazing by the zooplankton can be suggested as one of the causes for the decline in the
standing crop of phytoplankton. An inverse relationship in the distribution of phytoplankton
and zooplankton is usually discernible. Thus an explosion in the algal production is also due
to the comparative scarcity of zooplankton. A phytoplankton bloom naturally results in the
sudden depletion in the available nutrients in the euophotic zone and so such a bloom is
usually followed by a lower rate of production.
Zooplankton communities of fresh water bodies constitute an extremely diverse
assemblage of organisms represented by most of the invertebrate phyla (kumar et al., 2001).
Zooplankton has short life span and they respond more quickly to environment leads to
change in plankton communication in terms of tolerance, abundance, diversity and
dominance in the habitat. Therefore zooplankton communities of numerous reservoirs, lakes,
river and shallow water bodies have been used as indicators for the status of the lake and
river. The variability observed in the distribution of zooplankton is due to abiotic parameters
(Kolhe et al., 2013).
Zooplankton are the heterotrophic (sometimes detritivorous) type of plankton.
Zooplankton is a broad categorization spanning a range of organism sizes that includes both
small protozoans and large metazoans. It includes holoplanktonic organisms whose complete
life cycle lies within the plankton, and meroplanktonic organisms that spend part of their life
cycle in the plankton before graduating to either the nekton or a sessile, benthic existence.
Although zooplankton are primarily transported by ambient water currents, many have some
power of locomotion and use this to avoid predators (as in diel vertical migration) or to
increase prey encounter rate. Ecologically important protozoan zooplankton groups include
the foraminiferans, radiolarians and dinoflagellates (the latter are often mixotrophic).
Important metazoan zooplankton include cnidarians such as jellyfish and the Portuguese Man
o' War; crustaceans such as copepods and krill; chaetognaths (arrow worms); molluscs such
as pteropods; and chordates such as salps and juvenile fish. This wide range includes a
similarly wide range in feeding behavior: filter feeding, predation and symbiosis with
autotrophic phytoplankton as seen in corals. Zooplankton feed on bacterioplankton,
phytoplankton, other zooplankton (sometimes cannibalistically), detritus (or marine snow)
and even nektonic organisms. As a result, zooplankton are primarily found in surface waters
where food resources (phytoplankton or other zooplankton) are most abundant.
Water Quality Index (WQI)
Water quality index is most efficient tool of environmental audit process to convey
the overall water quality of a water resource. It is a rating of water quality parameters by a
single numerical expression reflecting the complete influence of water quality parameters on
the overall quality of water.
Water Quality Index (WQI) may be defined as the rating that reflects the composite
influence of a number of water quality factors on the overall quality of water. It reduces the
large amount of water quality data to a single numerical value. It is one of the most effective
ways to communicate information on water quality trends to policy makers, to shape sound
public policy and implement the water quality improvement programmes efficiently.
The present study deal with the “Study of planktonic community of Narmada River
with reference to hydrological study”.