species composition of marine microalgae in...

Chapter I

Species Composition of Marine Microalgaein Arokiapuram

lp

Studies on the Biotechnological Applications of Marine Microalgae

1. Introduction

Marine phytoplankton comprise a complex community of several thousands of

floating microalgae in the sea ranging in size from about 1 pm upto a few millimeters.

Based on their size. phytoplankton can be classified as macroplankton (more than

1mm), microplankton (less than 1mm, retained by nets of mesh size 0.06 mm),

nanoplankton (between 5 and 60 micrometers) and ultraplankton (less than 5

micrometers). Many phytoplankton species belong mainly to the nanoplankton and

microplankton fractions.

Studies on the various aspects of species composition, density, distribution and

seasonal variations of marine phytoplankton relating to coastal waters have been

carried out from various parts of the world by Ignatiades and Mirnicos (1977) from the

Sarnikos Gulf waters; Figueira (1989) from the Spanish waters of Atlantic coast;

Yong (1990) from Maxiwell Bay of George Island and Yamaguchi et al. (1994) from

Thale Sap Songkhia of Thailand.

Fritsch (1935), Singh (1939 a,b; 1942 a,c; 1941), Rao, (1939, 1940) and

Parukutty (1939, 1940) made effective contribution to the Indian flora of algae.

Publications by Iyengar and Desikachary (1944, 1946 a & b, 1953, 1954) and

Desikachary (1945; 1946 a & b, 1953) added considerably to the existing knowledge

of Indian algae, particularly the blue green algal flora of south India.

Chapter I- Species Composition of Marine Microalgae in Arockiapurani Coast

13


In India, such studies have been carried out from the east and west coasts.

Preliminary and systematic accounts on the phytoplankton of Madras coast

(Subrahmanyan, 1946) and the shore waters of Gulf of Mannar (Prasad, 1958) are

found to be very useful and significant. It was Menon (193 1) who reported for the first

time diatoms of the east coast of India. The distribution of phytoplankton of east coast

was studied by Shetty ci al. (1962), Santhakumari (1971), Vijayalakshrni and

Venugopalan (1973), Devendran ci al. (1974), Ramadhas (1977), Premila and Rao

(1977), Ragothaman and Rao (1978), Sundararaj (1978), Thankaraj et al. (1979),

Kannan and Job (1980), Ilangovan (1981), Chandran (1982), Ilangovan and

Krishnamoorthy (1983), Prabha Devi (1986), Mani ci al., (1986). Balusamy (1988),

Subramaniam and Bhavanarayana (1989), Gouda and Panigrahy (1996) and Bharati ci

al. (2001).

This was followed by the contribution to the phytoplankton flora of

Trivandrum coast by Nair (1959). Studies on the phytoplankton of the west coast of

India were carried out by Subrahmanyan (1960), Krishnamoorthy and Viswanathan

(1968), Gopinanthan ci al. (1970). Qasim ci al. (1972), Devassy and Bhattathira

(1974), Joseph and Pillar (1975), Kumaran and Rao (1975), Qasim and Gupta (1981),

Nair ci al. (1983), Rao ci al. (1989) and Nandan and Azis (1996). Lower species

diversity but higher phytoplankton standing crop and chlorophyll concentration have

been reported due to severe eutrophication from the Visakhapatnam harbour waters as

against near normal conditions of the open sea (Raman and Paniprakash, 1989).

Chapter 1- Species Composition of Marine Microalgae in Arockiapuram Coast

14


Seasonal distribution of marine phytoplankton and the seasonal averages of

primary production rates have been reported from different regions of the EEZ of

India (Supriya and Bhargava, 1993). The marine phytoplakton studies were also

carried out from the coastal waters of Tranquebar-Nagapattinam region

(Sampathkumar and Kannan, 1998), 65 species of diatoms, 25 species of

dinoflagellates and one species of blue green alga have been encountered. In the

Mandovi-Zuari nearshore waters of Goa, population density of marine phytoplankton

was studied by Rajagopal (1981); Bhargava and Dwivedi (1974); Bhargava et al.

(1977); Devassy (1983); Verlencar and Qasim (1985).

Phytoplankton characteristics of coastal and estuarine waters of India have also

been investigated by several authors (Jayaraman,1951; George, 1952; Jayaraman and

Seshappa,1957). Similarly, Gopinathan (1985) revealed the new distributional records

on the marine diatoms of Indian seas. Seasonal distribution and behaviour of nutrients

of Mulki estuary was by Vareethiah and Hanifa (1997), Vijayakumar et al. (2000) and

Rajesh et al. (2000). Mathew and Nair (1980) and Vasanthiamma (1991) studied the

planktonic diatoms and hydrography of the Vizhinjam coast.

On the east coast, in the Hooghly estuary of West Bengal, a total of 91 species

of phytoplankton have been recorded (Santra and Pal, 1989). Of these, 18 species

belong to blue greens, 7 to diatoms and 12 to dinoflagellates. Dc ci al. (1994)

observed the maximum number of phytoplankton species during the post-monsoon

Chapter I- Species Composition of Marine Microalgae in Arockiapuram Coast

15


and pre-monsoon seasons and Coscinodiscus radial us and C. excentricus together

contributed 50% of the total population of phytoplankton. Sivadasan and Joseph

(1997) studied the distribution and role of benthic microalgae in Cochin backwater.

Studies on the microalgae of the east coast have received only very attention.

Chapter 1- Species Composition of Marine Microalgae in A rockiapuram Coast

16


2. Material and Methods

Regular monthly collections samples were made from March 2001 to February

2002 from Arockiapuram coast. The microalgae were collected between 5.30 to 7.00

am with the help of a planktonic net of 38p.m mesh size. Immediately after collections

the samples were preserved in 2% formaldehyde. The cells were counted using a

counting chamber under lSOx magnification. Very small forms had to be counted

under with a magnification of 600x. In order to determine the numerical abundance of

phytoplankton depending on the cell concentration, either the whole sample or a part

(lrnl) of it was counted using 9 Sedwig- Rafter counting cell following Trivedi and

God (1986). The values for the whole samples were computed for cells/m 3 of water

and converted to percentage. Based on the climatic conditions prevailing in the

Kanyakurnari District, the study period (2001-2002) was divided into four seasons,

viz., pre-monsoon (March-May), south-west-monsoon (June- September), north-east-

monsoon (October and December) and post - monsoon (January and February).


17


3 Results

The seasonal occurrence of microalgae recorded at Arokiapuram during the

study period, 2001-2002, is presented in Table 1.

A total number of 48 different genera of microalgae were identified

representing 10 classes such as Bacillariophyceae, Chlorophyceae, Chrysophyceae,

Cyanophyceae, Euglenophyceac, Eustimatophyccae, Prasionophyceae,

Prymesiophyceae, Dinophyceae and Chryptophyceae. Among the 10 classes,

Bacillariophyceae was represented by more number of genera (18 numbers), followed

by Chlorophyceae (8 numbers), Prymensiophyceae (6 numbers), Prasinophyceae (5

numbers), Cyanophyceae (3 numbers), Chrysophyceae (2 numbers),

Eustirnatophyceae (2 numbers), Chrptophyceae (2 numbers), Dinophyceae (1 number)

and Euglenophyceae (1 number).

During the pre-monsoon season, among these 48 genera the Dicrateria

inornata was found in maximum (2564 cells/rn 3 ). Next to Dicrateria, the other species

like Coscinodiscus sp. (1296), Pleurosigma sp. (884 cells/rn 3) and Amphiprora

gigantea (764 cells/m 3 ) showed the maximum representation. This was followed by

Fragilaria sp. (481 cells/rn 3), Tetraselmis tetrahele (438 cells/m 3), Chromulina

feibergenesis (382 cells/rn 3 ), Nannochioropsis sauna (283 cells/rn), Chlamydomonas

sp. (251 cells/m 3 ), Chaetoceros calcitrans (233 cells/rn 3) and Streptotheca indica ( 1 84

cells/m, 3), Platymonas sp. (174 cells/m 3), Peridinium sp. (124 cells/m. 3 ), Chiorella


18


marina (103 cells/rn3), Rhizosolenia setigera (83 cells/m3), Chiorella ova/is (74

cells/m. 3), Ch/ore/la salina (62 cells/m 3), Cryptochrysis fulva (60 cells/m3),

Chaetoceros affinis (54 cells/rn 3 ), Navicula sp. (50 cells/rn 3) and Nitzschia closterium

(41 cells/rn 3). The rest of the species were found in negligible numbers (Table I).

Species such as Chroomonas sp., Teiraselmis gracilis, Dicrateria gilva, Isochrysis

galbana and Pavlova lutheri showed no representation in the pre-monsoon samples.

Among the 48 microalgac identified, the Bacillariophyceae constituted 47.27%

(Fig.2), followed by Pryrnensiophyceac (28.86%), Chlorophyceae (7.92%),

Prasinophyceae (5.47%), Chrysophyceae (4.26%), Eustimatophyceae (3.28%),

Dinophyceae (1.38%), Chryptophyceae (0.73%), Cyanophyceae (0.62%), and

Euglenophyceae (0.17%).

In the south-west-monsoon period, Isochrysis galbana showed the maximum

of 4891 cells/m 3 . followed by other species such as Chromulinafeibergenesis (4533

cells/rn 3 , Coscinodiscus sp. (3894 cells/rn 3), Dicrateria inornata (3581 cells/rn3),

Fragilaria sp. (2693 cells/m 3), P/eurosigma sp. (2094 cells/rn), Nannoch/oropsis

sauna (1784 cells/rn 3 ), Amphiprora gigantea (1681 cells/rn 3), Dicrateria gilva (1480

cells/m 3), P/atymonas (895 cells/m 3 ), Streptotheca indica (705 cells/m), Peridinium

sp. (581 cells/m 3), Chlamydomonas sp. (474 cells/m3), Chiorella marina (361

cells/rn 3), Cryptochrysis fulva (285 cells/m3), Chiorella ovalis (254 cells/rn3),

Tetraselmis tetrahele (231 cells/rn 3) and Chaetoceros calcitrans (186 cells/m'). The


19


rest of the species identified had very low percentage only (Table 1). Phaeocystis sp.

showed no representation during this season.

During this south-west-monsoon period, the classes Bacillariophyceae

constituted 39.84% (Fig.3), followed by Prymensiophyceae (31.07%), Chrysophyceae

(14.25%), Chlorophyceae (7.24%), Eustimatophyceae (5.53%), Dinophyceae (1.78%),

Prasinophyceae (1.02%), Chryptophyceac (1.07%), Cyanophyceac (0.34%) and

Eu glenophyceae (0.03%).

During the north-east monsoon period, Isochrysis galbana was found to be in

maximum number (3562 cells/rn 3 ). Next to this, Coscinodiscus sp. (2981 cells/m3),

Dicrateria inornata (2586 cells/rn 3), Amphiprora gigantea (2364 cells/rn3),

Pleurosigma sp. (2255 cells/rn 3), Nannochioropsis sauna (1875 cells/m3),

Chaetoceros calcitran.s' (1772 cells/rn3), Sireptoiheca indica (1653 cells/rn3),

Platyrnonas sp. (1564 cells/m3), Chiorella marina (1028 cells/rn 3), Rhizosolenia

setrigera (985 cells/m 3), Crvpiochysis virescens (694 cells/m 3), Chlamydornonas sp.

(585 cells/m 3), Phaeocystis sp. (484 cells/m 3), Chaetoceros affinis (361 cells/rn3),

Pavlova lutheri (285 cells/rn 3 ) and ChromulinafeibergenesiS (305 cells/m3 ) were seen

in the samples. Species such as Nannochioris atomus, Peridinium sp. and Tetraselmis

carterformis showed no representation during this season.

Among the 48 microalgae identified, the classes Bacillariophyceae constituted

49.39%, followed by Pryrnensiophyceae (25.54%), Chlorophyceae (12.95%),

Chapter I- Species Composition of Marine Microalgae in A rockiapuram Coast

20


Eustimatophyceae (6.81%), Chrypophyceae (1.83%), Cyanophyceae (0.5%),

Chrysophyceae (0.47%), Prasinophyceae (0.46%), and Euglenophyceae (0.12%). The

classes Dinophyceae had no representation (Fig.4) in the samples.

During the post-monsoon season, Dicrateria inornata was found to be

maximum with 3893 cells/m 3, followed by Isochrysis galhana (3256 cells/rn3),

Coscinodiscus sp. (2563 cells/m 3), Pleurosigma (2080 cells/rn 3 ), Fragilaria sp. (1684

cells/rn 3), Chromulina feihergenesis (1578 cells/rn 3), Ainphiprora gigantea (1298

cells/m 3), Platynonas (1163 cells/m 3), Chaetoceros calcitrans (1089 cells/rn3),

Chiorcila marina (854 cells/m 3 ), Peridiniu,n sp. (809 cells/m 3), Streptotheca indica

(775 eel ls/rn 3), Nannochioropsis sauna (693 cells/m 3), Phaeocystis (656 cells/m 3),

Ch/ore/la ova/is (569 cells/rn 3), Rhizosolenia setigera (486 cells/rn 3 ), Dicarteria gilva

(395 cells/rn 3 ), Chlamydomonas (296 cells/rn 3 ), Navicula (265 cells/rn 3 ), Chrootnonas

(208 cells/m 3), C,yptochrysis virescens (196 cells/rn 3 ).Cha etoceros affinis (155

cells/rn) and Tetraselmis carter formis (128 cells/m 3). Other species had only poor

presentation (Table 1). Species such as Nannochioropsis atomus, Synechocystis sp.,

Tel raselmis gracilis, Tetraselmis chuii, Pa y/ova salina and Ci yptochiysis fulva

showed no representation during this season.

During this season, the classes Bacillariophyceae constituted 41 .95%, followed

by Pryrnensiophyceae (31.61%), Chlorophyceae (11.66%), Chrysophyceae (6.80%),

Dinophyceae (3.08%), Eustimatophyceae (2.67%), Prasinophyceae (1.06%),


21


Chryptophyceae (0.74%) Cyanophyceae (0.28%), and Euglenophyceae (0.11%) as

given in Fig. 5.

The abundance of phytoplankton showed fluctuation during different seasons

of the study period. Among the 48 species of microalgae identified, the class

Bacilariophyceae came first with maximum number and it comprised 66.4% of total

population. The Pyremenesiophyceae constituted 29.3% in the total population. The

other classes such as Chlorophyceae, Chrysophyceae, Eumastigophyceac,

Pyrasinophyceae, Cyanophyceae, Dinophyceae, Cryptophyceae and Euglenophyceae

represented 9.5%, 6.5%, 4.6%, 2%, 2,1.4%, 1. 1, and 0.1% respectively (Fig. 6).

Two-way ANOVA test conducted for the population density between algae

(Table 2) was statistically significant (F=l 1.003; P<0.05) whereas non-significant

between seasons (F= 0.16; P>0.5)


22


Table I.I. Seasonal occurrences of Marine Microalgae (cells/M3) in

theArokiapuram sea during March 2001- February 2002

SI. _______ Seasons________ _______Classes Name of the microalgae P.M NEM PSMNo

5 174 291 1081. Bacillariophyceae Amphora sp.

(0.5) (0.53) (1.04) (0.41)

8 156 8 IS2. Bacillariophyceae Asterionellajaponica

(0.08) (0.47) (0.02) (0.05)

3. Bacil lariophyceac Chaetoceros affinis54 191 361 155

(0.60) (5.87) (1.29) (0.59)233 186 1772 1089

4. Bacillariophyccae Chaetoceros calcitrans (2.59) (0.57) (6.37) (4.14)

1296 3894 2981 25635. Bacillariophyceae Coscinodiscussp.

(14.46) (11.97) (10.71) (9.76)

764 1681 2364 12986. Bacillariophyceae Amphiprora gigantea

(8.52) (5.16) (8.49) (4.94)

- 184 705 1653 7757. Bacillariophyceae Streptotheca indica

(2.05) (2.16) (5.94) (2.95)-

24 12 108 948. Bacillariophyceae Cymbella sp.

(0.26) (0.03) (0.38) (0.35)-

12 11 105 819. Bacillariophyccae Fragilaria intermedia

(0.13) (0.03) (0.37) (0.30)

481 2693 110 168410. Bacillariophyceae Fragilariasp.

(5.36) (8.28) (0.39) (6.41)

-- 50 85 9 265II. Bacillariophyccae Naviculasp.

(0.55) (0.26) (0.03) (1.00)

41 - 8 254 8912. Bacillariophyceae Nitzschia closterium

(0.45) (0.02) (0.91) (0.33)

Contd........


23


SeasonsSl• Classes Name of the microalgaeNo

P.M SWM NEM PSM

24 35 95 6413. Bacillariophyceae Nitzschia sp.

(0.10) (0.34) (0.24)

884 2094 2255 208014. Bacillariophyceae Pleurosigma

(9.86) (6.43) (8.10) (7.92)

83 108 985 486IS. Bacillariophyceae Rhizosoleniasetigera

(9.26) (0.33) (3.54) (1.85)

34 124 84 9116. Bacillariophyccae Skeletonema costatum

(0.37) (0.38) (0.30) (0.34)

24 89 208 1517. Bacillariophyceae Thalussionema nitzschioides

(0.26) (0.22) (0.74) (0.05)

36 110 98 6118. Bacillariophyceae Thu lassiosira pseudonana

(0.40) (0.33) (0.35) (0.23)

20 75 65 8319. Chlorophyceae Chiorella vulgaris

(0.22) (0.23) (0.23) (0.31)

62 108 83 7420. Chlorophyceae Chiorella sauna

(0.69) (0.33) (0.29) (0.28)

________ -

74 - 254 71 56921. Chlorophyceae Chiorella ovalis

(0.82) (0.78) (0.25) (2.16)

103 361 1028 85422. Chlorophyceae Chiorella marina

(1.14) (1.11) (3.69) (3.25)

251 474 - 585 29523. Chlorophyceae Chlamydomonassp.

(2.80) (1.45) (2.10) (1.12)

14 38 110 2524. Chlorophyceae Dunaliella sauna

(0.15) (0.11) (0.39) (0.09)

Contd........


SI. ClassesNo I

25. Chlorophyceae

Name of the microalgae

Platymonas


24

33. Eustimatophyceae Nannochioropsis oculata

34. Eustimatophyceae Nannochioropsis sauna

Seasons

P.M SWM NEM PSM174 895 1564 1163

(1.94) (2.75) (5.62) (4.43)

12 41

(0.13) (0.12) - -

382 4533 305 1578

(4.26) (13.93) (1.09) (6.01)

102 205 208

- (0.31) (0.73) (0.79)

26 55 107 34

(0.29) (0.16) (0.38) (0.12)

17 48 12 41

(0.18) (0.14) (0.04) (0.15)

13 8 18 -

(0.14) (0.02) (0.06)

15 Ii 36 29

(0.16) (0.03) (0.12) (0.11)

11 16 22 8

(0.12) (0.04) (0.07) (0.03)

283 1784 1875 693

(3.15) (5.48) (6.74) (2.64)

8 47

- (0.02) (0.16) -

438 231 17 93

(4.88) (0.71) (0.06) (0.35)

23 14 35

(0.25) (0.04) (0.12 -

26. I Chlorophyceae Nannochloris atomus

27. Chrysophyceac Chromulina fi?ibergenesis

28. Chrysophyceae Chroom onus sp

29. I

Cyanophyceae Anabena sp.

30. 1 Cyanophyccae Oscillatoria sp.

31. 1 Cyanophyceae Synechocystis sp.

32. I Euglenophyceae Euglena gracilis

35. I Prasinophyceae Tetraselmis gracilis

36. I Prasinophyceae Tetraselmis tetrahele

37. I

Prasinophyceae Tetraselmis chuii

Contd...


KI


SeasonsSI. Classes Name of the microalgaeNo . P.M SWM NEM PSM

16 74 12838. Prasinophyceac Tetraselmis carierformis

17) (0.22) (0.48)

14 5 28 5639. Prasinophyceae Tetraselmis suecica

(0.15) (0.01) (0.10) (0.21)

1480 105 39540. Prymnesiophyceac I)icrateriagilva

- (0.37) (1.50)

2564 3581 2586 389341. Prymnesiophyccae Dicrateria inornata

(28.60) (11.01) (9.29) (14.8)3

4891 3562 325642. Prymnesiophyceae Isochrysisgalbana

- (15.03) (12.8) (12.40)

80 285 9843. Pryrnnesiophyceac Pay/ova luiheri

- (0.24) (1.02) (0.37)

15 72 8344. Prymncsiophyceae Pay/ova sauna

(0.16) (0.22) (0.29) -

8 484 65645. Prymnesiophyceae I'haeocystis sp.

(0.08) - (1.73) (2.49)

124 581 80946. I)inophyceae Peridiniumsp.

(1.38) (1.78) - (3.08)

60 285 6447. Chryptophyceae Cryptochiysisfulva

(0.66) (0.87) (0.23) -

6 - 64 694 19648. Chryptophyceae Ciypiochrysis virescens

(0.06) (0.19) (2.49) (0.75)

Note: Number within parenthesis denotes percentage

P.M= Pre-Monsoon; SWM= South-west-monsoon. NEM North-East Monsoon, PSM Post-Monsoon

Chapter 1- Species Composition of Marine Microalgae in Arockiapuram roast

26


Table 2. Two -way ANOVA of population density of various algae in

different seasons during the study period.

Source of Variation I SS I df I MS I P-value (5%)

Total Variance 1 2027.486 1 191

Variance due to Algae 1591.909 ' 47 33.87041 Significant

Variance due to Seasons 1.560239 3 0.52008 Non-significant

Error Variance 434.016 141 3.078128



Fig. 5 Percentage composition of microalgae during

the Post-Monsoon season at Arockiapuram sea

DBacillariophyceae

-. DChlorophyceae3161

-

41.9 5 -. OChrysophyceaeDCyanophyceae

-- •Eg'nopyceaeDEustimatophyceae

- - 0 Prasinophyceae

1.06--- :- -- :DPrymensiophyceae.DChryptophyceae1

- - - - -028-j 68

30



Fig. 5 Percentage composition of microalgae during

the study period Arockiapuram sea

31

6.

9.

., 1.4 1.1

10 Bacillanophyceaeo Prymnesiophyceae0 ChlorophyceaeO ChrysophyceaeD Eumastigophyceae0 Pyrasinophyceae0 CyanophyceaeO DinophyceaeOCryptophyceae

.DEuglenophyceae

66.4


32


4. DiscussionIn the present study, wide fluctuations in the population density of

phytoplankton were observed. Similar observations were reported from the Vellar

estuary by Chandrari (1985) and Mandovi-Zuari estuarine complex by Devassy and

Goes (1988). Regini (2004) also observed similar fluctuations in Rajakkamangalam,

Kadiapatinam and Manakkudy estuaries.

In the present study, among the identified classes of phytoplankton,

Bacillariophyceac (diatoms) were found dominant followed by Chlorophyceae and

others. Similar observations of dominance were made by Santhanam (1976) and

Sivakumar (1982) in Vellar estuary, Nair et al. (1987) in Ashtamudi estuary,

Gopinathan (1985) in Veil lake, Jagadeesan (1986) in Coleroon estuary, Balusamy

(1988) in Muthupet estuary and Shibu (1991) in Paravur lake. It is evident from

several works that diatoms and dinoflagellates are the predominant forms foundc

almost throughout the year in most of the Indian waters (Devassy and Bhghira. 1974).

Joseph and Pillai (1975) observed the abundance of diatoms in the monsoon and post-

monsoon seasons from the backwaters of Cochin.

Next to diatoms, dominance of green algae (Chlorophyceae) was recorded in

all the four seasons. Similar observations were reported by Gopinathan (1975) and

Mathew and Nair (1981) from the fresh water zone of Veil lake and Balusamy (1988)

in Muthupet estuary.


33


Jsochysis galbana, Dicarteria inornala and Cocinodiscus sp. were abundant

in all the seasons. This observation was supported by the findings of Asha et al. (2002)

with Coscinodiscus sp. in the Lakshadweep sea.

The percentage abundance of microalgae also depended upon the season.

There were no equal representation of the species and population density during

different seasons of the study period. Some of the algae that represented more in

number on one season could not be counted as the maximum in the other seasons

(Bai, 1997).

The phytoplankton density was found to be high during the monsoon and low

during pre-monsoon season in present study. Ramass (1977) in Porto Novo estuary;

Chandran (1982) in Vellar estuary; Jegadeesan (1986) in Coleroon estuary and Shibu

(1991) in Paravur lake also observed high phytoplankton density during monsoon and

low during pre-monsoon seasons. Chandran (1985) reported that the species

composition, bloom formation and population density were low during premonsoon

because of the greater seaward flushing and poor light penetration in Vellar estuary.

In the percent study 43 species of microalgae were recorded in the pre-

monsoon season, 47 species in south-west-monsoon, 45 species in north-east monsoon

and 42 species in post monsoon period. These findings are partly substantiated with

the observations made by Kannan (1980) on the diatoms species diversity of Porto


34


Novo, Tamil Nadu and De etal. (1994) in the species diversity of Hugh estuary, north

east coast of India.

Kannan (1996) has reported a total number of 126 species of phytoplankton

from Manauli and Hare islands of the Gulf of Mannar. But in the present study only 48

species could be recorded from Arockiapurarn sea.


species composition of marine microalgae in...

Documents