Paleofloristic and paleofaunistic analysis of Dudváh River oxbow and implication for Late Holocene paleoenvironmental development of the Žitný ostrov Island (SW Slovakia)
Abstract
Žitný ostrov, the largest island of the Danube River (SW Slovakia) gained its present shape in the Neoholocene period. As a result of increased flood and geomorphological Danube river activity dated to 1378-1528 AD, the Lower Dudváh River was abandoned and its alluvium became a part of the Žitný ostrov. Study of a Dudváh terrestrialized paleomeander by means of pollen and macrofossil analysis provides new information about the paleoenvironments of the Danubian Plain. The meander under study was cut-off during the Sub-Boreal period when the land was mostly covered by oak-dominated mixed forest with a notable high frequency of <italic>Fagus</italic> and <italic>Abies.</italic> In low-lying depressions, <italic>Alnus glutinosa</italic> formed typical alder carrs. The largest decline of the mixed forest occurred during the Sub-Atlantic period. Until the mid-19th century the region was strongly influenced by shallow groundwater and periodical floods, as reflected by pollen of aquatics and marsh species. Amongst non-arboreal taxa, pollen of Cyperaceae, Brassicaceae/<italic>Cuscuta</italic>, Poaceae and Apiaceae prevailed. Local successional changes started with i) stage of abandoned oxbow still with influx of moving water, poor in both macrophytes and molluscs, ii) shallow eutrophic oxbow lake with slowly flowing or stagnant water overgrown with aquatics (<italic>Ranunculus</italic> subgen. <italic>Batrachium, Potamogeton</italic> sp., <italic>Ceratophyllum demersum</italic> etc.) and abundant molluscs, iii) an open marsh dominated by Cyperaceae (mainly <italic>Carex riparia</italic>) with <italic>Atriplex prostrata</italic>, supporting diverse molluscan and Ostracod fauna. Present-day habitat is a result of landscape changes, which have been associated with draining, intensified agriculture, ruderalisation and spread of invasive species.
- Publication:
-
Geologica Carpathica
- Pub Date:
- December 2010
- DOI:
- 10.2478/v10096-010-0032-1
- Bibcode:
- 2010GCarp..61..513P
- Keywords:
-
- Holocene;
- SE Slovakia;
- paleoecology;
- palynology;
- paleomeander;
- Mollusca;
- Ostracoda;
- Dudváh River