Parcs

ID	TITEL	DATENTYP
38215	Masterarbeiten Nationalpark Neusiedler See - Seewinkel	Archive
37736	Botanik Nationalpark Neusiedler See - Seewinkel	Archive
38123	Universität Wien	Organisation/Institution

Bemerkungen/Beschreibung

Soda pans of the Carpathian basin are shallow saline lakes with variable water levels. They are critically endangered habitats of European concern. Conservation management is trying to revive traditional grazing in order to preserve the specialised halophytic vegetation surrounding these soda pans. However, explicit effects of grazing on halophytes are unclear apart from changes in community structure by supressing otherwise dominant species like Phragmites australis. This study asks whether low intensity shifting grazing by cattle in the Seewinkel area in Austria affects community composition, halophyte presence, species richness and abundance when reed dominated patches are excluded. I conducted 176 vegetation relevés on randomly chosen salinity-influenced sites around 19 soda pans and took soil samples to further determine the influence of conductivity and nitrate on vegetation. Additionally, I monitored shares of bare soil and reed abundance on the twelve grazed and seven non-grazed pans. In an AICc-based model selection approach grazing per se never showed a relevant influence on halophytes, while share of bare soil turned out to be the main environmental driver. As expected, soil conductivity shaped community structure as well as the ratio of halophyte to glycophyte abundance. Salinity was a relevant factor increasing the presence of two halophytic model species Puccinellia peisonis and Tripolium pannonicum but decreasing presence of glycophytes. Soil nitrate increased glycophyte relative to halophyte abundance and
the presence of reed. Reed cover still shaped plant communities, despite the pre&8208;selection of
study sites to exclude reed&8208;dominated habitats. All models showed higher values of explained
variance when the random effect of soda pan identity was considered, which indicates that other factors than the physical soil and vegetation characteristics measured here play an important
role as well. Re&8208;establishing connectivity between soda pans through grazing corridors
might be crucial for future halophyte population persistence. I conclude that herded cattle grazing at the current intensity does not pose any threat to halophytes around soda pans in the Seewinkel region and might even be slightly intensified without adverse effects.

Masterarbeit Uni Wien

Eintrag Nr. 38706

Halophytes at soda pans in northern Burgenland under the influence of soil conditions and conservation management