A study has been conducted during April-October 1991, to findout the different constituents of

Lab-Lab Present in four brackishwater aquaculture ponds. The Lab-Lab present in the culture systems were

mainly composed of blue green algae Oscillatoria sp. P honnidium sp, Lyngbya sp, Spirulina sp, and diatoms

Pleurosigma sp, Navicual sp, Amphora sp, Coscinodiscus sp, and micro fauna aopepod, amphipod, polychaete worms and lameli branch spat

Bensam, P

Madhu, K

Madhu, Rema

CMFRI Digital Repository

J. Andaman Sci. Assoc. 12 (1 & 2 ): 23-25,1996Observations on Lab-lab constituents in brackishwater ponds at CocliinREMA MADHU.K.MADHUandP. BENSAM*Central Marine Fisheries Research Inslitule,Cochin, 682 014, Kerala.ABSTRACTA  sludy has been conducJed during  A p r i l -O c to b e r  1991, lo  findoul ihe d ifferent conslitucnls of L ab-L ab  Present in fou r  brackish w ater aqacullurc ponds. TTie Lab-Lab present in the culture  systems were mainly com posed o f  blue green algae Oscillaion'a sp. P lionnidium  sp, Lyiigbya sp, Spirulina  sp, and d iatom s Pleurosifftia  sp ,N a v ic u a l 5^ , A m phora  NUzschio sp, C oscinodisais  sp, and micro fauna aopcpod, am phipod , polychaete worms and lamcli branch spat.Lab-lab Is the natural food In the culture system and it is composed of several m icroscopic organisms dominated by the blue green algae. These constituents of the biological plant and animal complex are suitable natural food for the culture of fin and shell fishes especially milk fish chanos chanos, mullets, prawns, etc. It also serves as a primary food resource In the earlier stages of life cycle of marine and brackish water organisms. The Lab'Lab has been utilised for the successful commercial culture of miikflsh in Indonesia Philippines and Taiwan (Schuster, 1952).In view of the Importance of Lab-Lab In food chain of fishes and prawns, it is very much essential to  study the constituents of Lab-lab in localities where culture operation is Intensive. Thus the present study emphasised to find out the constituents’ of Lab-lab present in the fish culture ponds at Cochin.MATERIALS AND METHODS To study the constituents of Lab-lab four aquaculture ponds, were selected at Cochin.Kerala, Station I Pokkali field at Cheral where seasonal culture of prawn and paddy cultivation are carried out during different seasons of the year,station coconut palm canal at Narakkal excavated between rows of coconut trees for irrigation and utilized as cuture system station IV the experimental perennial culture pond of Central Institute of Brackish water Aquaculture (CIBA) at Narakkal and station IV the supply canal of CIBA (F ig .-I). Fortnlnghtly collectionsFig. 1 : Map showing location of stations.Present Address  : Central Agricultural Research Institute. Port Blair. 744 101, Andamanswere made from these stations during April October, 1991. The Lab-lab is scraped off from the bottom of the ponds during low tide with a Lab-lab sampler consisting of a basal plate of 15 X 15 cm of Galvanised Iron Sheet, a sample of 10 X 10 cm^ was made up into known volume and prosnved fn 5% formalin for counting the algla complex under microscope.The micro-fauna associated with Lab-lab were separated by seving and preserved in 5% formalin with rose bengal.RESULTS AND DISCUSSIONSThe Lab-lab present in these stations were mainly composed of blue green algae Oscillatorja sp, Phormidium  sp, Lyngbya sp, Spirulina sp, diatoms Pleurosigma sp, Navicula sp, Nitzschia sp, Coscinodiscus sp, and micro fauna copepods, amphipods, polychaereabudance of Lat>-!ab constiuents incresed from April to May amounting to 18380, 18340, 12800, 11560/100cm^ and It declined to 2668, 1970, 2795, 4550/100 cm^ it and month of June In station 1.11, III & IV respectively. The abudance of Lab-lab has shown an Increasing trend in the post monsoon season and attained tfie maximum of 78580, 89970, 68705, 50475/100 cm^ In these four stations. (Flg.-2). The sudden fall in the month of June is attributed to the high influx of fresh water during the South west monsoon. The same relationship in the distribution of algal complex and diatoms in Cochin backwater during premonsoon, monsoon and postmonsoon period were also reported among other by Gopinathan (1972),' and Joseph and Pillal (1975). Among the various: environmental factors, salinity is found to have] significant influence on the existence of floraworms and lamellibranch spats. The numerical Table  1 : Filamentaj standing Crop o f dominart algae In different station during Aprll-O ctober 1991.S tations Estimated No. o f f ilam ents  (mean value O scllla toria  sp.)Mean le n g lf i o f f ilam en ts  (mm)Estim ated lengthy f ilam en ts /100 cm (mm)Cheral pokkall fie lds ' 1658 0.247 40911. Narakkal coconut grove 6366 0.264 1680III. CIBA experimental pond 4558 0.241 1098IV, CIBA supp ly canal 2175Phormidium sp.0.180 391Cherat pokkali fields 2125 0.241 512Narakkal coconut grove 2966 0.267 791III. CIBA experimental pond 3375 0.283 955IV. CIBA supply canal 2175 Lyngbya sp.0.180 391I. Cheral pokkali fields 800 0.155 124Narakkal coconut grove 708 0.140 99III. CIBA experimental pond 650 0.152 98IV. CIBA supply canal 1541 0.185 285and fauna in an esluarlne system {Bardach etal, 1972 and Harldas ef d/,1973). The length wise production of dominant blue green algae In the four stations are given In tabie-1. It is obsen/ed that the total length of Osclliatorla and Phormidium was relatlyeiy high at filamental standing crop of dominant algae In different stations during April-October 1991.Sanders (1958), Tang and Chen (1967) and Parulekar et al. (1975) reported that the nutrient status and texture of tlie  soil play an Important role in the production of flora and fauna in the bottom of the ponds. A comparison showed the total standing crop of Lab-tab to high In Coconut Palm canal at Narakl<al followed by Pol<kali field at Cheral, Experimental pond of CIBA and its supply canal (Fig.~2). This may be due to the nutrient status of the pond bottom.n « K sF}g. 2  : Variation in total number o f la b - ia b ’ constituents at different stations during Aprii-Oclober 1991.ACKNOWLEDGEMENTSThe authors are thankful to Dr. P.S.B.R. James, the former Director, C.M.F.R.I. Cochin for providing ail necessary facilities during the period of study and to Dr; A. K. Bandyopadhyay, Director, C.A.R.I. Port Blair for tfte encouragement,REFERENCESGardach J.E., Ryther J.H, and W.O. Mo. La^eney. 1972. Milk fish  cu ltu re  in A g r icu ltu ra l, the  fa rm in g  and Husbandary o f Freshwater and Marine Organisms, Interscience, New York, 313-3'19.Desai, S.N, and M. Krishnan Kutty. 1969. A comparison of the marine and estuarine benthic fauna of the near shore regions of the Arabian Sea. Bull. Natl. Insl. Sci, India, 30 (18): 677-606,Gopinathan, C.P. 1972. Some seasonal abundance of phytoplankton in the Cochin backwaters. J. Mar, Biol. Ass, India. 14 (2); 568-577.Haridas, P . , Madhupralap, M. and T.S.S, Rao, 1973, Salinity temperature, oxygen and zooplankton biomass of the backwaters from Cochin to Alleppey, Indian J, Mar. Sci. 2 (2): 94-102,Joseph, K,J, and V,K, Pillai. 1975, Seasonal and spatial d i s t r i b u t io n  o f  p h y to p la n k te r s  in  C o c h in  backwaters. Bull, Dept, Mar. Sci. Univ. Cochin 7 (1):171-180.Parulekar, A,H,, Rajamanickam, G.V. and S.N. Dwivedi. 1975. Benthic studies In Goa estuaries, II. Biomass and fauna! composition In the Zuari estuary, Indian J. Mar, Sci, 4 : 202-205.Sanders, H,L, 1958. Benthic studies In Buzzard Bay, I, A n im a l s e d im e n t  r e la t lo n a is h ip s .  L Im n o f, Oceanogr, 3 :2 45 -2 5 8 ,Schuster, W,H. 1952. Fish Culture In brackish water ponds of Java, Spc, Pubi, Indo, PacK. Fish, C o u n .: 2.Tang. Y.A, and S,H. Chen, 1967, A survey of algal pasture soils of Milkfish ponds in Taiwan, FAO Fish, Rep. 44 (3) : 198-209.

Observations on Lab-lab constituents in brackishwater ponds at Cochin

http://eprints.cmfri.org.in/11311/1/Observations%20on%20Lab-lab%20constituents%20in%20brackishwater%20ponds%20at%20Cochin_Journal%20of%20Andaman%20Science%20Association_K%20Madhu_1996.pdf

Observations on Lab-lab constituents in brackishwater ponds at Cochin

Abstract

Similar works

Full text

Available Versions

CMFRI Digital Repository