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1.INTRODUCTION
Themajorityofscientificworksonthestructureandspatialortemporaltrans-
formationsofmacrophytecommunitiesinwaterbodiescomefromnumer-
ousfloristic,ecologicalandphytosociologicalstudiesconductedinthe20th
century0Atpresent,thereisanincreasingneedfortheresultsofstudiesinto
suchcommunitiesinordertoenhancetheeffectivenessoffisherymanage-
mentandtheprotectionoftheenvironment,waterbodiesandwaterquality0
Suchresearchalsoenablesananalysisofvariousphenomenaandprocesses
inwaterecosystems0Oneoftheaimsofmodernhydroecologyistointensify
thestudiesintotheroleofthemainbioticandabiotic(environmental)factors
intheassemblyofaquaticplantcommunitieswiththeuseofanewgenera-
tionofanalyticsoftware0
Macrophytesareaquaticplants(hydrophytes)withtheexceptionofuni-
cellularandcolony-formingalgae0Taxonomically(Cook1983,1985),morpho-
logicallyandecologically(denHartog,Segal1964)variedasaplantgroup,
theycompriseallCharophyta,someBryophyta,afewPteridophytaand
asmallfractionofSpermatophyta0Thephotosynthesisingorgansofthese
plantsarepermanentlyimmersedinwaterorpartlyfloatingonthewater
surface0Somemacrophytesfloatonthewatersurfaceorunderthewater;
theycanbeanchoredinthesubstrateorstayintouchwiththebottomwith-
outbeingattachedtoit0Someofthemhaveemersedassimilationandre-
productionorgansandsomedonot(Hutchinson1975)0Thearchitectureof
macrophytesisvaried:theycanbeeithershort,rigidandevergreenortall,
flexibleandoverwinteringasperennatingforms0Theformerspeciesdevelop
ground-levelrosettesconsistingofshortandrigidleavesresistanttotearing
byhydrodynamicforces0TheseareplantssuchasLittorellauniflora,Lobelia
dortmanna,Isoëteslacustris,IuncusbulbosusandRanunculusreptans0Thelat-
tergroupismadeupofplantshavingtallshootswithacentrallylocated
mechanicaltissue,whichmakesthemtenuousandresistanttobendingand
stretching0TheseincludeMyriophyllumspicatum,Elodeacanadensis,Stuckenia
pectinata,Potamogetoncrispus,Nupharspp.andNymphaeaspp.forexample0
