:.: :,)i:.j THE I]NIVERSITY OF MANITOBA Newly Covered Grass As HabÍtat For Fish In Bung BoraPed, Thaíland by Plodprasop Suraswadi A THESIS SUBMITTED TO THE FACULTY OF GRADUATED STUDIES IN PARTIA], FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF ZOOLOGY ,;,.;ti:..tl :':-r:'::'il':l I,üTNNIPEG, MANITOBA FA].L, L976 ..NEWLY COVERED GRASS AS A HABITAT FOR FISH IN BUNG BORAPED, THAILAND'' by PLODPRASOP SURAShIADI A dissertation sub¡nitted to the Faculty of Graduatc Studics of: thc Univcrsity of Manitoba in partiat full'illnrcnt ol' thc rcquirctncnts ol'thc dcgrcc ol' DO(]TOR OF PHILOSOPI{Y @ ï976 Penr¡issir¡rr l¡as bcc¡r grantcd to thc LllllìARY {)¡; T'llU UNlVEll- Sll'Y Ot; ùlANlT0lJ^ to lcnd or sell copies otì this clisscrtittiou, ttr the' NATIONAL LIBRAI{Y OF (:ANAI)A to nricrolittn this dissertation and to len<l or sell copios ol'tlte filnt, tnd UNtVERSI'tY MICROFILMS tr¡ publish rn ubstrlct of this dissertation. The author reserves other publication rights, and neithcr the dissertation nor extensivc cxtracts lionr it uray be printed or utltcr- wise reproduced without tltc autl¡or's writtcn purttrission. ( .:._ ,f,l:,!:,41,:_' Ì.::i.: j,i,:"t.Ì:;f rl.:, ...1::." i::1::.-t::i-. r:.1. :i.:,: ::ì-i t:l:-::: .::::,a,:-,::: !"j:1:"-.::"::a:: t,t-,1 'rl1:ï::::: ):'-1. .... tt DEDICATION To my mother K00NY ING KRONGTONG SURASI^'AD I with great respect and-my fondest love. lt¡ ABSTRACT The characteristics of the grassy habitat, weed covered habitat and open water habitat are described in relation to succession stages. Fish fauna, ,,,, _:. "l stomach contents, benthos, vegetation and associated fauna, water and sediment brere determined. The'effect of continuous water cover on grass-covered habitat *"s evaluated, .l in the attempt to immitate the early succession stage after ' draining and refi l l ing. Information mechanisms ,i about the invoìved in the nutrient cycle and the :,, effects of water level variations on the food chain were obtained. The ¡nter- . I relationshÌp between flora and fauna, especial ly-the advantage of grasses compared to floating weeds for locally important fish species, was studied. This information will be used to improve management and increase fîsh production in Bung Boraped and other reservoirs of Thailand. ' The established grass-covered habitat represents the early impoundment stagecharacterizedbyrapiddecomposition,abundanceofnutrient,highproduc- tionofbenthicorganisms,invertebrateSaSSociatedwithemergentgrasseSandsmall r f ish. The so.i I had lrigh organic matter and a high phosphorus content. ,'j' : -.... Leersia hexandra, Hymenachne pseudoiterum and Cynodon dactylon were the major , , macrophytes. The increas.ing populations of such fish species as Tr.ichogaster pectoral is, T. trichopterus, Cyclochei I ichthys enoplos, Amblyrhynchichthys truncatus, Lusionsoma bleekeri and Anabas testudineus indicated high ecological p roduct i on . The weed-covered habitat represents the late succession stage, charac- terized by low production of benthic organisms and fish, and unfertile soil sediment. The obnoxious plants such as Eíchornþ qrassipes,' Salvinia cucullaiqq, ¡V lsachne globosa and Coix aquatica were abundant and HrS occurred underneath the mats,creating anoxic conditions. The carnivorous fish specÎes such as 0phicephalus strîatus,0phicephalus lucius, 0phicephalus micropeltes,0mpox bimaculatus and \,/al lagonia attu were abundant, indicating a compì icated food ,.ì... web and I ow eco I og i ca I p roduct i on . The open-water habitat represents the intermediate zone characterized by better r¡rater quality, abundance of bentho-planktonic forms and versatile ,,,, pìanktonic feeders such as Paralaubuca sp. and Cirrhinus micropeltes: .,,, Bung Boraped could be maintained at a highly productive level if much of ,,'.,:' the natural communìty were periodically destroyed before it reached the matura- tion stage. Water level manipulatîon in summer appears to be appropriate for maximîzing fish production. By this process the grass-covered habÌtat, which is most favourable for fish production, would be re-establ ished. ACKNO\,ILE DGHENTS 0n behalf of the NatÌonal lnland FÎshery Institute, Thaìland, the author wìshes to thank the canadÎan lnternational Develópment Agency, of the Freshwater lnstitute, Winnipeg, l,lanitoba and the Department possible' Zoology at the university of Manitoba for making this research to his suPer- . The authoF wishes to exPress'hîs deep apprecÎation visor,DF.R.H.'Green,forhÌsencouragementandsuPportduringthe and criticism inception of thìs research and for hîs valuabìe suggestions and Dr' throughout the work. Thanks to Dr. C.C. Lindsey, DF' K' Patalas helpful l.W. Dickson who served as thesis committee members for their crltlclsm. Theauthoris.gratefuìtoMr.V.Varigul,theDirectorofthe National lnland Fishery lnstitute, Thai land, under whose authority to research in ThaÌland was carried out. Gratitude is also extended Dr. G.H. Lawìer the Director-General of the h/estern Region, Fisheries work in and Harine service, Environment Canada, under whose authority Canada w¿s done. of The author wishes to grateful ly acknowledge the contribution Hr. v. BoonyaratplÎn, Head of the Nakhon sawan Fishery station, who the prôvided accommodatt'on, tfansPortation and hospital ity throughout study period. Thanks are extended to Hr' S' Chareonpong' Mr' P' Siritantrapon and Mr. T. Vasupital< for their invaluable fieìd assistance the soÎl and thro.ughout this study. A special thanks to the staff of laboratory Water Anaìysis Unit, Chemistry Agficultural Division, for H'K' assistance on soi ì analysis, Apprecîation is also extended to Hs' Friesen for critÎcally editing the manuscript' vl Last, but by no mean least, sincere grat¡tude is extended to my wife, Thanya, and my two ìittle sons¡ PÎnsai and Pinsuk who received far less than their share of attention during the work. Their strength dur Io.ng absences f rom Thai land were a constant ':::':'::::.:::, and understand ing ing .my ,,,.:,r,,i:;, inspiration to me. i:J f:.- 1.:-lIì. ;':;.::.1 :.r i - Ît.l 1 TABLE OF CO}¡TEI{TS PAGE iii ABSTRACÏ --- v ACKNOWLEDGIIENTS --------- víii LIST OF TABLES xviii LIST OF FIGURES 1 INTRODUCTION ----- 6 MATERIALS AND METHODS ----------- 30 RESULTS 30 lJa te r 40 Sed i ment 54 macrophytes -------: ------ -- Aquatic -- 69 Invertebrates associated with aquatic macrophytes to Benth i c fauna 103 abundance -- Fish relative LLl Fish stomach contents 140 D ¡ SCUSS I ON ----- *:îï:"::-::::::l:::-::-:::::l::-::-:1:-::::::::::-- , 140 Techniquetorestorethereservoìrproductivity--_- 155 l. Water level maniPÚlation 155 of continuous water cover on a 2- Establ ishment l-58 grass-covered hab i tat 165 L ITERATURE C ITED vt | | LI ST OF TABLES TABLE PAG E | . Physical and chemical properties for oPen-water -;:::.:_.:' .l968-1975. region Ìn Bung Boraped, ìB 2. AquatÌc macrophytes found in Bung Boraped Reservoir, tglu-1975. l9 3. Gastropoda found in Bung Boraped Reservoir, 197\- 1975. z2 4. Pelecypoda found in Bung Boraped Reservoir, 197\- 1975. 23 5. Fish fauna found in Bung Boraped Reservoir, 197\- 2tl 1975. 6. Fish landing statisticsfor Bung Boraped Reservoir, 29 1965-1975. 7. The nutrient elements and major ions in water samples from the Grass Area (a). 37 8. The nutrient elements and major ions in water samples 3B from the Weed Area (c). 'g. The nutrient elements and major ions in water sampìes 39 f rom the Open Ì./ater Area (D) . 10. Analysis of variance for organic matter anÐng the the Grass Area (g) , the t'/eed Area (C) and the Open l^later Area (o) , excl udi ng the dry rnonths 4T llaY'A'nut t 1975 Il. Analysis of variance for Phosphorus among the IX PAGE TABLE the Grass Area (.9) , the. lJe.ed Area (c) and the Open Water Area (D), excludìng the dry months I f'laY-flugust 1975' 43 12. Ana lys is of variance for P.hosphorus between the Weed Area (C) and the Open Water Area (0) over the period'of l4 months, including the dry months May- August 1975. 43 13. An."lysis of variance for FÎne sand fraction (o.z-o.ooz mm) among the G.us Ar.u (g),. the l'Jeed Area (c) and the Open Water Area (0) ' excludinE the dry months MaY-August 1975. 45 14. Analysis of variance for Fine sand fraction (O.Z- Open 0.002 mm) betrveen the \'/eed . Area (C) and the Water Area (O) over the period of l4 months, I+5 incìudíng the dry months Hay-August 1975' 15. Analysis of variance for Silt fraction (O.Z-0.002 mm) among the Grass Area (g), the Weed Area (C) and the Open Water Area (O), excluding the dry months 46 Hay-August 1975. iì,, 16. Anaìysis of variance for si ìt fraction (o.oz-o.ooz i- --: -i .. mm) between the Weed Area (C) and the Open Water Ar.ea (O) ove r the per i od of ì 4 months , i ncl ud ing the dry months Hay-August 1975. :-------- 17. The analysis of variance for Cìay fraction (ìess than g) .,;,,;,¡.,;,, 0. 002 mtn) among t he G ras s Area ( , :1.: l:ii:: :i: :,: -:l-,.:-'- rl, ---:* -'--,. -:-. Ì.-:.i'.',.--.1-1."."j. ..:.-.:ìilr:::,::; PAGE TABLE .The Weed Area (c) and the Open Water Area (p), excludi.ng the d¡y months Hay-Augusl 1975' ?FãF-F-FFF 49 The analysi's of variance for CIa.y fraction (less lB¡ :_,,.. than O.002 mm) between the Ueed Area (C) and the (O) per i od of I 4 months , open l^Iater Area over the . incIuding the dry months Hay-August 1975' .... 19. The mean and 95Î.u conf i dence ì ìmits of o.rganic i.,'. l :'1': Hatter, Phosphorus and Partlcìe sìze Distributîon 51 în soi I samp'le f rom the Grass'Area (n)' ------:------ 20. The mean and 952. conf i dence I i mi t s of 0.rgan i c Hatter,PhosphorusandParticleSizeDistribution in soi I sampìe f rom the \^/eed Area (C)' 52 2l - The mean and 95lz confi dence t i *i ts of O.rgan ic Hatter, phosphorrs ånd part i cì e si ze Di stri bution in soil samples from the Open Water Area (0)'' 53 :cover ZZ.