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andfeatureswhichvarywithincertainlimits.Crossingtheselimitsmayleadto
speciation(Valladares,Gianoli,Gomez2007).
TheEuropeanwhitebirchisahabitat-formingspecieswithabroadecological
scale,resistanttoenvironmentalpollution.Thesetraitsareallthemorevaluable,
becausewithinindustrialdistrictsthereareconsiderableareasofpost-industrial
wastelands,andbirchisasuitablespeciesfortheirafforestation.Athorough
knowledgeofthedevelopmentalbiologyofaBetulapendulaRothpopulationandits
responsetovariableenvironmentalconditionscanprovidepracticalbasesfor
introducingthisspeciesintheareasaffectedbylong-lastinganthropopressure.
Theprocessofvegetationdevelopmentinopenpost-industrialwastelandsisstill
hardlyexplored.Itisworthwhiletoexaminethespatialvariabilityofvegetation
encroachingontheseareas,aswellastowhatextentthelifeconditionsand
individualtraitsarereflectedintheirspatialorganization.Spatialorganizationof
plantpopulationsisoneveryinteresting,althoughobviouslydifficultecological
issues.Theproblemconsistsininvestigatingthecausesbehindtheformationof
specificspatialstructuresandconsequencesofdifferentwaysofspatialoccupation
byspecimensfacedbyapopulationanditssurroundings(Bergon,Mortimer,
Thompson1999;Falińska2002).Still,theprecisedeterminationofthespatial
structuretypemustbeaprerequisiteforthiskindofresearch.Thedistributionof
plantsisdeterminedbyapossibilityoftheirgrowthanddevelopment,aswellasby
manyhabitatfactorsandinteractionsbetweenspecimensoftheirownandother
species(Bergon,Mortimer1981;Krebs2011).
Whenanalysingthephenomenonofspatialvariabilityofplants,particular
attentionwaspaidtoinfluenceexertedbydifferentabioticfactors.Thefollowing
factorswereusuallytakenintoaccount:water,lightandsoilproperties,andthus
factorsthatdeterminetheincreaseandthedevelopmentofplants(Bolibok2002).
Togetherwiththedevelopmentofplantecology,therewereattemptstoconsider
severalfactorsinecologicalprocessesaltogether.Whentryingtomodelthese
relationships,largegapswererevealedandinabilitytodeterminetheresultsoftheir
totalinfluence,whichinturndoesnotpermitgeneralizationoftheserelationships.
Comprehensiveresearchonspatialvariabilityofplantsandtakingintoaccount
severalvariablesinoneanalysis,isnowpossibleduetoadaptationof
thegeostatisticalmethodforspatialanalysisofdatavariability.Forbetter
comprehensionandunderstandingofthespatialstructureofB.pendulainthisstudy,
apartfromclassicalstatistics,alsoanewmethoddescribingthevariability1
geostatistics1wasapplied.Geostatisticaltoolsprovideapossibilitytodescribe
spatialvariabilityofthestudiedvariablesbymeansofafew,easilyinterpretable
parameters1sill,nugget,range(Kapusta2004).Itprovidesanopportunityfor
comparisonofthespatialstructureofmanyvariableswithinoneresearchplotand
singlevariablesbetweendifferentplots.
Theresultsofthepresentedstudycanconstituteanewsourceofknowledge
aboutthedevelopmentofvegetationcover,whichencroachesondegradedareasof
post-industrialwastelands.
Thefollowingresearchhypothesesweredefined.
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