Algal assemblage types of bog-lakes in Hungary and their relation to water chemistry,hydrological conditions ad habitat diversity

摘要

Algal flora of 12 bog lakes was investigated during the period of March 1995 to August 1999 in Hungary.Of the 129 samples,624 taxa of algae were identified.Species richness of individual samples ranged between 8 and 107 except the extraordinarily species rich Balate-to where 533 algal taxa were observed.Ordination of the samples resulted in five groups:(1)assemblages sominated by chlorococcalean algae and planktonic cyanoprokaryota;(2)assemblage dominated by flagellates (Dinophyta,Crystophyta,Euglenophyta,hrysophyceae,Raphido phyceae);(3) chlorococcalean algae and cyanprokaryotic assemblages with desmids,cryptophytes,dinoflagellates or euglenophytes as subdominants(4)assemblages dominated by diatoms and (5)a group of sample where other N and P,moreover,theri eater chemical chardcteristic (including pH and conductivity)were rather uniform.Therefore,other factors than chemical properties were responsible for different flora.The above groups were characteristic to certain types of habitats.In the first groupl,plankton samples from relatively large pools with considerable open water can be found.The second group included samples taken from small bog pools.The third group contained the periphyton amples form macrophytes,livig in bogs with constantly relible water supply.Samples of group four and five comprised samll gogs that occasionally dry up.Periphyton of lakes with Sphagnum belonged exclusively to the fifth group.This study has showen that small bog-pools are often inhabited by different species of flagellates and desmids are not as important as it has been widely believed.Hydrological properties and habitat diversity are the major factors influencing species richness of Hungarian bog-lakes.