Agglutinated foraminifera from the Chilka Lake, Orissa, east coast of India

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1 Indian Journal of Geo-Marine Sciences Vol. (), April 1, pp Agglutinated foraminifera from the Chilka Lake, Orissa, east coast of India R. Anil Kumar *, K. Bangaku Naidu & R. Kaladhar Department of Geology, Andhra University, Visakhapatnam - 3, India *[E.Mail: profkaladhar@gmail.com, anilgeo@gmail.com] Received December 13; revised February 1 Sediment and water samples were collected at stations from the Chilka Lake during May and December, 9 for foraminiferal studies and determination of important sediment and water parameters. The salinity ranges from 7.9 to.9, the temperature range is from 3. o to 3 o C, the dissolved oxygen content ranges from. to. ml/l and the substrate of the lake is characterized by sand, silty sand, muddy sand, clayey sand and sandy clay. Sand dominates the other types of substrate towards the mouth of the channel at Arakudha Village. Organic matter content of the sediment varies from.31 to. %. Fifteen agglutinated foraminiferal species - Ammobaculites agglutinans, A. directus, A. exiguus, Ammotium fragile, Gaudryina exilis, Haplophragmoides canariense, Jadammina macrescens, Miliammina fusca, M. fusca var., Reophax dentaliniformis, Textularia earlandi, Tiphotrocha kellettae, Trochammina advena, T. hadai and T. ochracea of which Miliammina fusca, M. fusca var. and Ammobaculites exiguus are of abundant occurrence tolerating relatively higher salinity and temperature. [Keywords: Chilka Lake, Agglutinated Foraminifera, Organic Matter] Introduction The Chilka Lake is a brackish water lagoon, spreading over the Puri, Khurda and Ganjam Districts of Orissa State on the east coast of India. The western and eastern margins of the lake are fringed by the Eastern Ghats 1. It is the largest coastal lagoon (1, 1 km ) in India and the second largest in the world. It is located between 19 ' and 19 ' N and ' and 3' E (Fig. 1)..3 to. m in the dry season and 1. to. m during the rainy season. The width of the Old Channel (Magarmukha) is about m. The lake is divided into four separate zones: the southern, central and northern sectors, and the outer channel area. The 3 km-long outer channel connects the lake with the Bay of Bengal at Arakudha Village. The lake is vaguely pear-shaped and has a maximum length of.3 km with a mean width of.1 km. Materials and Methods Sediment samples for foraminiferal studies, sediment texture analysis and determination of organic matter content and water samples for the determination of salinity and dissolved oxygen content were collected from stations (Fig. ) Fig: 1 Location map of the Chilka Lake A km-long barrier beach called Rejhansa formed by northerly currents in the Bay of Bengal resulted in the formation of this lake that forms its eastern side. Several inland rivers such as Bhargavi, Daya, Makara, Malguni and Nuna carry freshwater and silt into the lake. It is estimated that 13 million tons of silt is brought annually into the lake by rivers and rivulets that drain into it 3. The depth of the lake varies from Fig: Map showing the sample location in Chilka Lake

2 3 INDIAN J. MAR. SCI., VOL., NO. APRIL 1 during May and December 9 (pre-monsoon and post-monsoon seasons) from the lake. Temperature and hydrogen-ion concentration were measured at all the stations. Living foraminifera and sediment and water characteristics were determined following standard methods (living fauna, sediment texture -7, organic matter, salinity and dissolved oxygen 9, Systematic scheme has been followed for identification and classification of foraminiferal genera -11. The foraminifer s crop was counted and studied under the stereo binocular microscope. Results and Discussion During the observation period, bottom water salinity ranges from 3. at station in the central sector to 33.3 at station 11 in the outer channel in December. It varies from 7.9 at station in the central sector to. at station in the outer channel. Salinities are recorded somewhat higher in the outer channel in May. Bottom water temperature has range of 3. o C at station in the outer channel to 9. o C at station 3 in the central sector in December. It ranges from 9. o C at station in the outer channel to 3. o C at 11 stations out of the stations. It is more or less uniform in the lake in May. Dissolved oxygen ranges from. ml/l at station 1 in the northern sector to 7. ml/l at station in the outer channel in May. It varies from.1 ml/l at station in the southern sector to. ml/l at station 7 in the outer channel in May. The dissolved oxygen content of the waters of the outer channel dominates that of the other three sectors where it is more or less uniform. Greater water circulation and presence of some phytoplanktons obviously result in higher concentration of dissolved oxygen in the outer channel. Higher values of dissolved oxygen, especially in the outer channel, supports larger populations of the species. P H ranges from. at station at station in the northern sector to. at station 9 in the southern sector in December. It varies from. at station in the northern sector to. at station in the southern sector in May. The p H of the waters of the outer channel and northern sector are somewhat higher than that of the other areas of the lake. The p H of the waters of the lake, it is observed that, has no much effect on the agglutinated species. The substrate of the lake is characterized by sand, silty sand, muddy sand, clayey sand and sandy clay. Sand dominates the other types of substrate towards the mouth and clayey sand towards the southern part of the outer channel. Northern Sector consists of mostly sandy clay while the central and southern sectors are dominated by clayey sand type of substrate. Organic matter content of sediment ranges from.31 % in May in the outer channel to.1 % in December in the northern sector. Calcium carbonate of the sediments of the Chilka lake has not been determined by us but as per the investigation. Values of the calcium carbonate are low. It is about.1% near the Daya River, ranges from. to.7 % in the northern sector,. to. % in the central sector and 1.7 to. % in the southern sector. The following river water, shells and tests of organism and chemical precipitation from the lagoon water might be the sources for the calcium carbonate in the sediments of the Chilka lake. Sediments of the northern sector consist of somewhat higher organic matter by the inflowing rivers and streams into the Lake. Sand is poor and sandy clay and clayey sand are rich in organic matter content especially in December (Tables 1-3).

3 ANIL et al.: AGGLUTINATED FORAMINIFERA FROM THE CHILKA LAKE, INDIA 33 Table-1. Ecological parameters determined for the Outer Channel of Chilka Lake Station Salinity ( ) Temp.( C ) Dislsoved P H Sediment Organic Depth of the numbers oxygen(ml/l) type Matter (%) water May Dec May Dec May Dec May Dec May & Dec May Dec May Dec sand sand sand sand sand Silty sand Muddy sand Clayey sand Clayey sand Clayey sand Clayey sand Clayey sand Clayey sand Clayey sand Sandy clay Table-. Ecological parameters determined for the Northern sector of Chilka Lake Station Salinity ( ) Temp.( C ) Dislsoved P H Sediment Organic Depth of the numbers oxygen(ml/l) type Matter (%) water May Dec May Dec May Dec May Dec May & Dec May Dec May Dec Sandy clay Clayey sand Clayey sand Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Clayey sand Sandy clay Sandy clay Sandy clay Sandy clay

4 3 INDIAN J. MAR. SCI., VOL., NO. APRIL 1 Table-3. Ecological parameters determined for the Central and Southern Sectors of Chilka Lake Salinity Temp.( C ) Dislsoved P H Sediment Organic Depth of Station ( ) the numbers oxygen(ml/l) type Matter (%) water May Dec May Dec May Dec May Dec May & Dec May Dec May Dec Central sector Sandy clay Sandy clay Clayey sand Clayey sand Clayey sand Clayey sand Sandy clay Sandy clay Clayey sand Clayey sand Clayey sand Clay sand Clay sand Clay sand Clay sand Southern sector Clayey sand Clayey sand Clayey sand Clayey sand Clayey sand Fifteen agglutinated foraminiferal species viz; Ammobaculites agglutinans, A. directus, A.exiguus, Ammotium fragile,gaudryinaexilis, Hapl -ophragmoides canariense, Jadamminamacrescens Miliamminafusca, M. fusca var., Reophax dentalinif ormis, Textularia earlandi, Tiphotrocha kellettae, Trochammina advena, T. hadai and T. ochracea occur in the Chilka Lake. All these agglutinated species except Ammobaculites agglutinans have been identified 13-1 from the Chilka Lake. Among all the agglutinated forms, Miliammina fusca, M. fusca var. and Ammobaculites exiguus are of abundant occurrence and hence their occurrence and distribution in the Chilka Lake in relation to ecology have been discussed in detail. The other agglutinated forms are of common to scarce occurrence and are not much significant in relation to ecology and hence have been described briefly in Table.

5 ANIL et al.: AGGLUTINATED FORAMINIFERA FROM THE CHILKA LAKE, INDIA 3 Table-. Agglutinated species of common to scarce occurrence Species Ammobaculites agglutinans No. of stations L: 7 T: 3 Maximum population L: 11 T: Distribution Living individuals are found at stations 1, 3,, and to 13. Dead tests occur at all stations except at stations3,, 7, 9, 3, 37, 3,, 1,, and. A. directus T: 31 Ammotium fragile T: Gaudryina exilis T: T: T: T: Living specimens are absent. Dead tests occur at all stations exceptstations1,,,,, 1, 1, 19,,, 7, 9, 31,,,, and 9 Living specimens are absent. Dead individuals occur at stations, to 17,, 1,, 7, 9 to 39, 1 to and 7 to Living specimens are absent. Dead specimens occur at stations, 11 to 1,,, to and. Haplophragmoides canariense T: T: Living specimens are absent. Dead tests occur at stations 1 to 3,,, 9 to 11, 13 to 1,, 31 to 3,, 7 and 9. Jadammina macrescens T: T: Living specimens are absent. Dead tests occur at stations to1, 1,,,, 3, 33, 3 to, 7, and. Reophax dentaliformis T: T: Living specimens are absent. Dead tests occur at stations 1 to, 7, 9,,,, 17, 19,,, 7, to 3, 3 and 7 to. Textularia earlandi L: T: 7 Tiphotrocha kellettae T: L: T: T: Living specimens occur at stations 1 and 9 to. Dead tests occur at stations 1 to,, to, 17, 19,,, 7,, to 33, 3, 7, 9 and. Living specimens are absent. Dead tests occur at stations to, 17, 19,,,, to. Trochammina advena L: 9 T: L: T: 9 Living specimens occur at stations, 9, 11, 13 to1, and. Dead tests occur at stations 1 to, to 17,,, to, 3, 3, 37,, to, 9 and. T.hadai L: 7 T: L: T: Living specimens occur at stations, 13 to, and 3 to. Dead tests occur at stations, 3,, 7, 9 to 1, 1,, 7 to 9, and to T.ochracea L: T: L: T: 9 Living specimens occur at stations, 11, 1,, 3 to.dead tests occur at stations to19, 1, to, and 3 to. A maximum of 3 species at station 9 in May and species at station in December are found in living condition in the outer channel. Total population of Miliammina fusca varies from species at station in the central sector in May. It ranges from species at stations and 3 in the outer channel to 17 species at station 7 in the northern sector in December. Total populations between and species occur at stations,,, and 9 in December in the Northern Sector. At the remaining stations, the total populations are less than species. Distribution of absolute sizes of living population shows that Miliammina fusca blooms in May and is a dominant species in the Outer Channel in this season. Reduced abundances in December compared to those of May suggest that it is able to survive the higher temperatures and salinities in summer. Miliammina fusca has been shown to reproduce and survive at temperatures o to o C and salinities to 3 -. Present study shows that Miliammina fusca is tolerant of salinity as high as 39. and temperature as high as o C. Of the three abundant agglutinated forms in the Chilka Lake Miliammina fusca is most abundant. The distribution patterns of living and total (living + dead) populations of Miliammina fusca in the lake are represented in Fig.3

6 3 INDIAN J. MAR. SCI., VOL., NO. APRIL Miliammina fusca The species bloom in the Outer Channel first in May and later in December. It has its spurt of reproduction activity in the lake subsequently in May probably at selected centers. In 3 the Pudimadaka Stream Miliammina fusca var. shows an antipathic relationship with Miliammina fusca in distribution and that it occurs in a very limited range of different ecological conditions in December and probably too sensitive to fluctuations in the latter to survive in other seasons. But in the Chilka Lake its relatively large-sized living populations occur in both the seasons under widely varying ecological conditions. The distribution patterns of living and total (living + dead) populations of Miliammina fusca var. in the lake are represented in Fig Miliammina fusca var Fig. 3. Histograms showing the distribution patterns of living and total (living + dead) populations of Miliammina fusca in the chilka lake. Neither living nor dead specimens of Miliammina fusca var. are found at stations 1,, 1, 1 and 31. The standing crop of the size of to 17 specimens/unit volume wet sediment occurs at stations,,, 3,, 9, 37, 3, and 9 in May and at stations,,, 13, 1,, 3 to 3, 1 to 3 and 9 in December. The size is less than specimens at the rest of the stations. Total population size varies from to 9 specimens at stations, 3,, 9, 3 to and 9 in May and at stations, 13, 1, to, 3 to 3, 1 to 3 and 9 in December. At the remaining it is less than specimens STATION NJMBERS Fig..Histograms showing the distribution patterns of living and total (living + dead) populations of Miliammina fusca var. in the Chilka Lake

7 ANIL et al.: AGGLUTINATED FORAMINIFERA FROM THE CHILKA LAKE, INDIA 37 Living population size of Ammobaculites exiguus ranges from to specimens at stations, 7 to 11, 1, 19, 1,,,, 9, 31, 3, 39, 3,, and in May and at stations, 7,, 11, 13, 1 to 1, 19,,, 3,, 31, 33, 3, 3, 3 and 7 to in December. At the rest of the stations it is less than specimens. Total population size ranging between and 1 specimens occur at stations,, 9, to,,,, 9, 31,, 1, and in May and at stations 9, 13 to, 17, 1, to, 31, 3, 9 and in December. At the rest of the stations, it is less than specimens. Total populations are of much larger size than the corresponding living populations. Consideration of the living and total population distributions shows that the ecological conditions are more favourable in the outer sector and some parts of northern and central sectors in the lake. Ammobaculites exiguus colonizes only the outer channel and some parts of northern and central sectors. Ammobaculites exiguus is an abundant species in the Gosthani Estuary as also in the Pudimadaka 7 and in the Balacheruvu streams. Its large-sized populations occur in the Gosthani Estuary at salinity. to 31. and at temperature. o to 3 o C. It reproduces more actively around salinity and temperature more than o C and in the Pudimadaka Stream and Suddagedda Estuary at salinity and temperature to and o to 3 o C, respectively. Ammobaculites exiguus in the Choptank River, Maryland, a part of the Chesapeake Bay estuarine system occurs at a temperature range of o to o C and a salinity range of. to 1.. The present study shows that Ammobaculites exiguus reproduces at salinities higher than 3. as has been noted 3 in the Pudimadaka Stream. The distribution patterns of living and total (living + dead) populations of Ammobaculites exiguus in the lake are presented in Fig.. Conclusion The Chilka Lake is a brackish water lagoon. Based on the physical and chemical parameters, the lake is divided into southern, central and northern sectors and the outer channel. Sediment and water samples were collected from stations in the Chilka Lake for foraminiferal studies. Fifteen agglutinated foraminiferal species viz., Ammobaculites agglutinans, A. directus, A. exiguus, Ammotium fragile, Gaudryina exilis, Haplophragmoides canariense, Jadammina Ammobaculites exiguus Fig.. Histograms showing the distribution patterns of living and total (living + dead) populations of Ammobaculites exiguus in the Chilka Lake. The occurrence and distribution of agglutinated foraminiferal species of common to scarce occurrence are summarized in Table. macrescens, Miliammina fusca, M. fusca var., Reophax dentaliniformis, Textularia earlandi, Tiphotrocha kellettae, Trochammina advena, T. hadai and T. ochracea have been identified, among which Miliammina fusca, M. fusca var. and Ammobaculites exiguus are of abundant occurrence. In general, agglutinated species can withstand higher salinities and temperatures. In the Chilka Lake, the three abundant species mentioned above could survive even at higher salinity and temperature conditions.

8 3 INDIAN J. MAR. SCI., VOL., NO. APRIL 1 PLATE 1. Agglutinated foraminiferal species in the Chilka Lake 1) Reophax dentaliniformis: General view. x, ) Miliammina fusca (a) Four chamber side. x (b) Three chamber side. x 3) Miliammina fusca var.: General view. x ) Ammobaculites agglutinans: General view. x 19 ) A. directus: Side view x ) A. exiguus: General view. x 17 7) Ammotium fragile (a) Side view x 1 (b) Apertural view x 7 (c) Side view x 1 ) Textularia earlandi (a)general view x 1 9)Tiphotrocha kellettae (a) Dorsal view x (b) Ventral view x 7 ) Trochammina advena (a) Spiral side view. x (b) Details of the aperture. x References 1. Tripathy, Balaram (7-11). Maritime Heritage of Orissa. Orissa Review (Govt. of. Orissa): pp Singh, Sarina: Joe Bind Loss, Paul Clammer, Janine Eberle. (). India, Lonely Planet, pp Chilka Lake Development Authority, Orissa. (). History of Chilka Lake. International Lake Environment Committee (ILEC, ). Chilka lagoon experience and lessons learned brief. Asish, K. Ghosh, C.E.D. and Ajit, K. Patnaik, CDA. Pp Walton, W. R. (19). Techniques for recognition of living Foraminifera. Contr. Cushman Found. Foram. Res., Vol. 3, pp. -.. Carver, R. E. (Editor). (1971). Sedimentary petrology. John Wiley and sons, Inc., London, 3p. 7. Folk, R. L. (19). The distinction between grain size and mineral composition in sedimentary rock nomenclature. Jour. Geol., Vol., pp Sverdrup, H. U., Johnson, M. W. and Fleming, R. H. (19). The Oceans Prentice-Hall, New York, 7 p. 9. Strickland, J. D. H. and Parsons, T. R. (19). A practical hand book of sea water analysis. Bull. Fisheries Res. Board of Canada, No. 17, 311p.. Loeblich, A. R. Jr, and H. Tappan (19). Foraminiferal genera and their classification. Van Nostrand Reinhold Company, New York. 11. Boltovskoy, E. and Wright, R. Recent foraminifera, Dr. W. Junk K B V, Publishers, The Hague, K. Venkata Ratnam (19). Studies on some aspects of the sediments of the Chilka Lake (A Coastal Lagoon). Ph.D. Thesis Andhra University, Waltair (unpublished). 13. Jayalakshmy K. V. and Kameswara Rao K. (1). Frequency distribution of foraminifera in the Chilka Lake. Jour. Mar. Bio. Ass. India, 3 (1&); pp Kameswara Rao K. et al, (). Foraminifera from the Chilka lake on the east coast of India. Jour. Mar. Bio. Ass. India, (1&); pp Boltovskoy, E. and Boltovskoy, A. (19). Foraminiferos Tecamebas de la Parte Inferior Del Rio Quequen Grande, Provincial de Buenos Aires, Argentina. Inst. Nac. De Invest. De las Cienc. Nat., Hidrobiologia, Tomo II, pp Boltovskoy, E. and Lena, H. (199). Seasonal occurrences, standing crop and Production in benthic Foraminifera of Puerto Beseado. Contr. Cushman Found. Foram. Res., Vol., pp Schafer, C. T. and Sengupta, B. K. (199). Foraminiferal ecology in polluted estuaries of New Brunswick and Maine. Atlantic Oceanographic Labor atory, Bedford Institute, Dartmouth, N.S., Canada. R eport A.O.L., 9-1 (Unpublished manuscript). 1. Murray, J. W. (19a). The living Foraminiferida of Christchurch Harbour, England. Micropaleontology, Vol. 1, pp Elision, R. L. and Nichols, M. M. (197). Estuarine Foraminifera from the Rappahannock River, Virginia, Contr. Cushman Found. Foram. Res., Vol. 1, pp McCrone, W. A. and Charles, S. (19). Geochemical and sedimentary environments of Foraminifera in the Hudson River estuary, New York. Ibid., Vol., pp Coss, D. and Madeira, M. L. (19). Seasonal variations of brackish Foraminifera in the Patos lagoon, Southern Brazil. Univ. Federal Rio Grande do sul, Escola Geol., Publ. Espec. No., pp Freudenthal, M. D., Lee, J. J. and Pierce, S. (193). Growth and physiology of Foraminifera in the laboratory. Pt.. A tidal system for laboratory studies on eulittoral Foraminifera. Micropaleontology, Vol. 9, pp Venkata Rao, T. (197). Recent Foraminifera from the marginal marine environments between Visakhapatnam and Kakinada, East Coast of India. Ph.D. Thesis submitted to the Andhra University (Unpublished).. Nageswara Rao, J. (1979). Studies on Foraminiferida from the Gosthani estuary and the Visakhapatnam shelf and sediments, East Coast of India. Ph.D. Thesis, Andhra University, Waltair. (Unpublished).. Narappa, K. V. (19). Recent Foraminifera from the Godavari and Krishna River estuaries, East Coast of India. Ph.D. Thesis Andhra University, Waltair (Unpublished).. Kaladhar, R. (191). Recent Foraminiferida from the Balacheruvu streams Tandava River estuary, and Rishikonda Rock Pools, East Coast of India. Ph.D. Thesis submitted to Andhra University (Unpublished). 7. Venkata Rao, T. (197c). Studies on Foraminifera of Pudimadaka stream, East Coast of India. Jour. Ind. Acad. Geosci.. Buzas, M. A. (199). Foraminiferal species densities and environmental variable in an estuary. Limnology and Oceanography, Vol. 1, pp. 11-.