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10Introduction
Charalesalsobelongheredespitebeingfairlyhigh,anchoredandgenerally
inelastic0Macrophytesusetheirresourcesnotonlytogrowandreproduce
butalsotoanchorinthesubstrate(Szmeja2006)0
Themorphologicaldiversityofmacrophytesmayimpacttheformation
ofspatiallyandtemporallypersistentplantstructures0Thedifferentiationof
communitiescanbebasedontherepetitionofspeciescombinations,asinthe
French-Swissschoolofphytosociology(Braun-Blanquet1964),aswellason
speciesdominance0Thedominancecriterionenabledthecreationofaclear
systemofcommunitiesshowingtherealpictureofaquaticvegetationand
facilitatingthecomparisonofplantsfromvariouswaterbodies0Irrespective
oftheoccupiedpartoftheaquatichabitat,beitsurface,underwater,shal-
low-waterordeep-water,thecommonfeatureofmacrophytecommunities
ininlandwatersistheirsimplestructure(Szmeja2006)0Thesecommunities
areexceptionallypoorwithregardtofloraandcharacterisedbyacleardomi-
nanceofonespecies,ormoreseldomtwoco-dominants(Chmaraetal02015)0
Theremaybemanyreasonsfortheformationofsuchastructure,butitis
probablytheabioticfactorsthatplaytheprimaryroleinthisprocess0What
otherfactors–abioticorbiotic–are(orcanbe)responsibleforsuchatype
ofstructures?Isthesimplepatternoftheunderwatercommunityderived
fromthepressureofenvironmentalfactors?Ifso,fromwhichofthefactors
describedasregulatorsofvegetationstructure?Whatistheimpactofsuch
environmentalfactorsaslight,depthorwateracidity/alkalinityonthecom-
munitypattern?
Despitethewealthofliteratureontheconditionsunderwhichaquatic
plantcommunitiesareformed,thesignificanceofeachoftheenvironmental
factorsisstillunclear0Theformationanddifferentiationofsuchcommunities
isanopenissueandrequiresfurtherstudy0Itshouldbeunderlined,however,
thatclonalplants,whichefficientlypopulateandfillintheemptyspace,are
dominantamongmacrophytes0Thankstotheirstructureandabilitytospread,
mostmacrophytesarecosmopolitanspecies0Whatismore,manyofthemare
characterisedbyfairlyhighpolymorphismandhighphenotypicplasticityin
responsetoenvironmentalfactors(Sculthorpe1971;Barrat-Segretain1996;
Santamaria2002)0Iassumethatthisisoneofthemainreasonswhymany
communitiesveryoftenconsistofjustafewspecies0Theformationofper-
sistentandrepetitiveassemblagesmadeupoffourormorespeciesisarare
phenomenoninwaterbodies,especiallyunderthewater,andnotnecessarily,
itwouldseem,dependentonlyonthephysicalandchemicalpropertiesof
theenvironment0Thepersistenceofrepetitivecombinationsofco-occurring
speciesinagivenlakemaybeofcrucialimportance0Inthiswork,Iassume
thatnewrarelyusedmethodsofordinationandotheranalyses,suchasclas-
