Tharavathy N.C. et. al. / International Journal of Modern Sciences and Engineering Technology (IJMSET)
ISSN 2349-3755; Available at https://www.ijmset.com
Volume 3, Issue 4, 2016, pp.19-22
Studies on the occurrence of hydrophytes in relation to water parameters
in fresh water ecosystems in Dakshina Kannada
Sr. Daina Marina Fernandes1
M.Sc. Biosciences
Department of Biosciences
Mangalore University
Mangalore-574199, Karnataka
[email protected]
Sandhya2
M.Sc. Biosciences
Department of Biosciences
Mangalore University
Mangalore-574199, Karnataka
*
Tharavathy N.C.3
Associate Professor
Department of Biosciences
Mangalore University
*Corresponding Author
[email protected]
Abstract
Studies were carried out in two natural (pond 1 and 2) and two artificial (pond 3 and 4) freshwater
ponds to study the occurrence of hydrophytes in relation to water parameters. The values of pH recorded in
water samples in pond 1 and 2 were 5±0.71 and 6±0.71 respectively and in both artificial ponds, it was
6.5±0.71. The temperature recorded was 32±1.410C and 34±1.410C in natural ponds 1 and 2 and 30.5±2.120C
and 29±1.410C in artificial ponds 3 and 4 respectively. Dissolved oxygen was 23±2.83 mg/l and 19.5±2.12 mg/l
in natural ponds 1 and 2 and 17.5±0.71 and in artificial ponds 3 and 4, it was 19.5±2.12 mg/l respectively. BOD
was recorded as 26.5±0.71 mg/l and 21± 1.41 mg/l in natural ponds 1 and 2 and 18.5±3.54 mg/l and 19.5±2.12
mg/l in artificial ponds respectively. Phosphate was 15±7.07 mg/l and 7±2.83 mg/l in natural ponds 1 and 2
and in artificial ponds 3 and 4, it was 10.25±0.71 and 17±11.31 mg/l respectively. The biodiversity of
hydrophytes were studied in all four fresh water ponds and they were identified. It was found that in natural
ponds 1 and 2 Potamogeton sp., Isoetes sp. and Typha sp. were abundant, whereas in artificial pond 3, Pistia
sp. and Eichhornia sp. were abundant and in artificial pond 4, Hydrilla sp. and Lemna sp. were abundant.
Key words: Hydrophytes, Dissolved oxygen and Biological oxygen demand.
__________________________________________________________________________________________
1. INTRODUCTION:
Plants which grow in wet places or in water either partly or wholly submerged are called
hydrophytes or aquatic plants. Examples are Utricularia, Vallisneria, Hydrilla, Chara, Nitella, Lotus,
Ceratophyllum, Trapa, Pistia, Eichhornia (water hyacinth), Wolffia and Lemna. Aquatic environment
provides a matrix for plant growth in which temperature fluctuation is at minimum and the nutrients
occur mostly in dissolved state but light and oxygen become deficient with the increase in depth of
water bodies. According to their relation to water and air, the hydrophytes are grouped into three
categories. They are submerged hydrophytes, floating hydrophytes and amphibious hydrophytes (Palit
and Mukherjee, 2012). Submerged hydrophytes are plants which grow below the water surface and
are not in contact with atmosphere. They may be free-floating or rooted, for example Vallisneria,
Hydrilla, Potamogeton and Najas, Ceratophyllum, Mynophyllum, Utricularia, Chara and Nitella.
Floating hydrophytes are plants that float on the surface or slightly below the surface of
water. They are in contact with both water and air and may or may not be rooted in the soil. On this
ground, the floating plants have been divided into free floating hydrophytes and floating but rooted
hydrophytes. Free floating hydrophytes are plants which float freely on the surface of water but are
not rooted in the mud. Examples are Wolffia arhiza and Wolffia microscopica (a rootless minute duck
weed), Trapa bispinosa, Lymnanthemum, Eichhornia crassipes (water hyacinth), Salvinia (a fern) and
Azolla (a water fern). Floating but rooted hydrophytes are submerged plants that are rooted in muddy
substrata of ponds, rivers and lakes but their leaves and flowering shoots float on or above the surface
of water, for example Nelumbo speciosum (Lotus), Victoria regia (water lily) and Ceratopteris
thalictroides (a hydrophytic fern of family Parkariaceae).
Amphibious hydrophytes are adapted to both aquatic and terrestrial modes of life. They grow
either in shallow water or on the muddy substratum. Amphibious plants which grow in saline marshy
places are termed as „halophytes‟. Roots and some parts of stems and leaves in these plants may be
submerged in water or buried in mud but some foliage, branches and flowering shoots spring well
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Tharavathy N.C. et. al. / International Journal of Modern Sciences and Engineering Technology (IJMSET)
ISSN 2349-3755; Available at https://www.ijmset.com
Volume 3, Issue 4, 2016, pp.19-22
above the surface of water or they may spread over the land. Present paper comprises the study of
occurrence of hydrophytes in relation to the water (physico-chemical) parameters in fresh water
ecosystems in Dakshina Kannada district.
2. MATERIALS AND METHODS:
Total 4 fresh water ponds were selected for the study. Among the 4 ponds, 2 were natural
ponds (pond 1 and 2) i.e. situated in Ujire, Dakshina Kannada district and other 2 ponds were artificial
ponds (pond 3 and 4) i.e. constructed manually for growing hydrophytes. The water samples from
four fresh water bodies were collected from lentic zones at a depth of 5-10 cm from the surface.
Samplings were done between 4 to 6 p.m. Water samples were collected in plastic containers and
brought to the laboratory. Physical parameters i.e. temperature and pH were measured immediately in
the field. Fixation of dissolved oxygen is performed on the site. In the laboratory, chemical
parameters i.e. dissolved oxygen (DO), biological oxygen demand (BOD) and phosphate were
analysed. All the parameters were analysed according to the standard methods prescribed in APHA,
2005. The hydrophytes were identified in all four water bodies simultaneously. It was compared with
the physico-chemical characteristics of the respective water bodies.
3. RESULTS AND DISCUSSION:
The values of physico-chemical parameters in all four fresh water samples are showed in Fig.
1 and 2.
3.1 PHYSICAL PARAMETERS
3.1.1 pH
It is important to test the pH - the level of acidity or alkalinity - of water. It is one of the most
important measurements commonly carried out in natural and waste waters. pH is defined as the
logarithm (base 10) of the reciprocal of the hydrogen ion concentration. Most natural waters are
generally alkaline due to the sufficient amount of carbonates. pH of water gets drastically changes
with time due to the exposure to air, temperature and biological activity. pH values of water samples
recorded during the study period are represented in Fig. 1. It was recorded 5±0.71 and 6±0.71 in
ponds 1 and 2 respectively and in both artificial ponds, it was 6.5±0.71.
3.1.2 TEMPERATURE
The most common physical assessment of water quality is the measurement of temperature. It
is one of the important abiotic factors in the ecosystem and impacts both the chemical and biological
characteristics of surface water. It affects the dissolved oxygen level in the water, photosynthesis of
aquatic plants, metabolic rates of aquatic organisms, and the sensitivity of these organisms to
pollution, parasites and disease. The values of temperature in water samples recorded during the study
period are represented in Fig. 2. It was 32±1.410C and 34±1.410C in natural ponds 1 and 2 whereas in
artificial ponds 3 and 4 it was 30.5±2.120C and 29±1.410C respectively.
3.2 CHEMICAL PARAMETERS
3.2.1 DISSOLVED OXYGEN (DO)
Dissolved oxygen (DO) is the amount of oxygen present in the water. It is measured in
milligrams per liter (mg/l), or the number of milligrams of oxygen dissolved in a liter of water.
Oxygen gets into water by diffusion from the surrounding air, by aeration (rapid movement), and as a
waste product of photosynthesis. DO is a very important indicator to detect the ability of water body
to support aquatic life. Analysis of DO plays a key role in water pollution control and waste water
treatment process. DO values of water samples recorded during the study period are represented in
Fig. 3.2. It was 23±2.83 mg/l and 19.5±2.12 mg/l in natural ponds 1 and 2 and in artificial ponds 3
and 4, it was 17.5±0.71 and 19.5±2.12 mg/l respectively.
3.2.2 BIO-CHEMICAL OXYGEN DEMAND (BOD)
Biochemical oxygen demand or biological oxygen demand (BOD) is the amount of dissolved
oxygen needed (i. e., demanded) by aerobic biological organisms to break down organic material
present in a given water sample at certain temperature over a specific time period. The BOD value is
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Tharavathy N.C. et. al. / International Journal of Modern Sciences and Engineering Technology (IJMSET)
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Volume 3, Issue 4, 2016, pp.19-22
most commonly expressed in milligrams of oxygen consumed per liter of sample during 5 days of
incubation at 20 °C and is often used as a surrogate of the degree of organic pollution of water. BOD
can be used as a gauge of the effectiveness of wastewater treatment plants. BOD values of water
samples recorded during the study period are represented in Fig. 2. It was recorded as 26.5±0.71 mg/l
and 21± 1.41 mg/l in natural ponds 1 and 2 and 18.5±3.54 mg/l and 19.5±2.12 mg/l in artificial ponds
3 and 4 respectively.
3.2.3 INORGANIC PHOSPHAT
Phosphrous in natural fresh water is mostly in inorganic form H3PO4, HPO4 & PO4. Major
source of phosphorous in water are domestic sewage, detergents, agricultural effluents with fertilizers
and industrial wastewater. High concentration of phosphorous is an indication of pollution. Phosphate
values of water samples recorded during the study period are represented in Fig. 1. It was 15±7.07
mg/l and 7±2.83 mg/l in natural ponds 1 and 2 and in artificial ponds 3 and 4, it was 10.25±0.71 and
17±11.31 mg/l respectively.
20
18
16
14
12
10
8
6
4
2
0
Fig. 3.1: Variations in pH and
Phosphate
40
Fig 3.2: Variations in
Temperature, DO and BOD
35
Temperature
('C)
DO (mg/l)
30
pH
Phosphate
(mg/l)
25
20
15
10
5
0
Pond 1
Pond 2
Pond 3
Pond 4
Pond 1
Pond 2
Pond 3
Pond 4
3.3 HYDROPHYTES
As the aquatic environment is uniform throughout, the hydrophytes develop very few
adaptive features. Root systems in hydrophytes are poorly developed which may or may not be
branched in submerged hydrophytes. In aquatic plants, stem is very delicate and green or yellow in
colour. In some cases, it may be modified into rhizome or runner. In floating plants, leaves are
generally peltate, long, circular, light or dark green in colour, thin and very smooth. Some aquatic
plants develop two different types of leaves in them. This phenomenon is termed as heterophylly.
Examples are Sagittaria, Salvinia and Azolla. The anatomical modifications in hydrophytes are
increase in the aeration, reduction of supporting or mechanical tissues and reduction of vascular
tissues, reduction in protecting structures where cuticle is totally absent in the submerged parts of the
plants. It may be present in the form of very fine film on the surfaces of parts which exposed to
atmosphere. Epidermis in hydrophytes is not a protecting layer but it absorbs water, minerals and
gases directly from the aquatic environment. Extremely thin cellulose walls of epidermal cells
facilitate the absorption process. Epidermal cells contain chloroplasts, thus they can function as
photosynthetic tissue, especially where the leaves and stems are very thin, e.g. Hydrilla. Hypodermis
in hydrophytes is poorly developed. Its cells are extremely thin walled. Stomata are totally absent in
submerged parts of the plants. In some exceptional cases, vestigial and functionless stomata have
been noticed. Aerenchyma in submerged leaves and stem is very much developed. Air chambers are
filled with respiratory gases and moisture.
The distribution, abundance, structure and diversity of hydrophytes are affected by several
environmental factors and biological interactions (Lacoul and Freedman, 2006). Some important
environmental factors are associated with light requirements of plants (Tremp, 2007), sediment
characteristics (Paal et al., 2007), trophic status (Kocic et al. 2008), and hydrology (Tremolieres et al.,
1994). The hydrophytes were identified in all four fresh water ponds. It was found that in natural
ponds 1 and 2 Potamogeton sp., Isoetes sp. and Typha sp. were abundant, whereas in artificial pond 3,
Pistia sp. and Eichhornia sp. were abundant and in artificial pond 4, Hydrilla sp. and Lemna sp.
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Tharavathy N.C. et. al. / International Journal of Modern Sciences and Engineering Technology (IJMSET)
ISSN 2349-3755; Available at https://www.ijmset.com
Volume 3, Issue 4, 2016, pp.19-22
were abundant. Varshney (1981) pointed out that certain aquatic plants like Lemna sp., Eichhornia
sp., and Utricularia sp. can be used as pollution indicator.
4. CONCLUSION:
The study of occurrence of hydrophytes in relation to water parameters revealed that water
in natural pond was slight acidic in nature than artificial ponds where the pH was almost neutral.
Temperature of water was fluctuated more in artificial ponds than natural ponds. In natural ponds
relatively more DO and BOD was recorded. The level of phosphate was variable in all four ponds.
The biodiversity study showed more diverse population in natural ponds than artificial ponds which
were constructed for mono or mixed cultures.
ACKNOWLEDGEMENTS:
The authors are thankful to the authorities of Mangalore University for providing the laboratory facilities.
REFERENCES:
[1].APHA-AWHA-WPCF. Standard methods for the examination of water and wastewater, 21st Edition,
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[2].Kocic, A., Hengi, T. and Horvatic J., 2008. Water nutrient concentrations in channels in relation to
occurrence of aquatic plants: a case study in eastern Croatia, Hydrobiologia, Vol. 603, p 253-266.
[3].Lacoul, P. and Freedman, B. 2006. Environmental influence on aquatic plants in fresh water ecosystems,
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[4].Paal. J, Trel and Viik, 2007. Vegitation of Estonian watercourses, III, Drainage basins of the Moonsund Sea,
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[5].Palit, D. and Mukherjee, A., 2012. Studies on water quality and macrophyte composition in wetlands of
Bankura district, West Bengal, India, Ind. J. Plant Sci., Vol. 02-03, p 221-228.
[6].Tremolieres, M., Carbiener, R. Ortscheit, A. and Klein, JP, 1994. Changes in aquatic vegetation in Rhine
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[7].Tremp, H. 2007. Spatial and environmental effects on hydrophytic macrophyte occurrence in the upper
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AUTHOR’S BRIEF BIOGRAPHY:
Sister Daina Marina Fernandes is an M. Sc. student in the Department of Biosciences,
Mangalore University. She is a student of the third author Dr. Tharavathy N.C., Associate
Professor, Department of Biosciences, Mangalore University. She did project work on
hydrophytes and their habitates under Dr. Tharavathy N.C. during her M.Sc. studies.
Miss Sandhya is also studying in M. Sc. in the Department of Biosciences, Mangalore
University and is a student of the third author Dr. Tharavathy N.C., Associate Professor,
Department of Biosciences, Mangalore University.
She is interested to study on
hydrophytes and their habitates and hence did project work under Dr. Tharavathy N.C.
during her M.Sc. studies.
Dr. Tharavathy N.C., obtained her M.Sc., M.Phil. and Ph.D. in Biosciences at the Dept.
of Biosciences, Mangalore University. Currently she is working as Associate Professor in
the Department of Biosciences, Mangalore University and guiding three Ph.D. scholars in
the field of Environmental Science. She has published a book entitled “Metals and
pesticides impact on algae and protozoa” in International Publisher LAP LAMBERT
Academic Publishing, Germany (ISBN: 978-3-659- 41234-9). She has presented 16
research papers in National and International Seminars/Conferences and published 20
research articles in different National and International Journals. She has also received
“Best Women Scientist Award” from Karnataka Science Congress in the year 2010. She
is a Life Member of National Environmental Science Academy, New Delhi and Editorial
Board Member of Asian Journal of Environmental Science.
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