Can a benthic diatom community complement chemical analyses and discriminate between disturbed and undisturbed saline wetland habitats?

Abstract

Soda pans are protected in the EuropeanUnion as Natura 2000 areas in the category of‘‘Pannonic saline steppes and marshes’’. There are atleast six soda pans of reference status in Serbia andonly a half have strict legal protection. The number ofsimilar, but disturbed (modified) habitats that could bereconstructed is still unknown. We conducted samplingin five natural and two disturbed soda pansaiming to compare a difference in physical andchemical water properties and benthic diatom communities.In addition, we tried to apply recentlydeveloped Diatom Index for Soda Pans (DISP) andTrait-based index (TBI) to test the applicability oftaxonomic and trait-based approaches in ecologicalstatus assessment of soda pans in the southern part of the Carpathian Basin. In contrast to natural soda pans,lower pH and nutrients levels were recorded indisturbed pans. A total of 86 taxa of benthic diatoms,including 11 new for diatom flora of Serbia, wereidentified. A lower species richness and Shannonindex was recorded in natural soda pans. Nitzschiaaustriaca, N. supralitorea, Navicula veneta and N.wiesneri were dominant diatoms in soda pans of thereference status. Both diatom indices were in averagelower in disturbed pans, and this difference wasstatistically significant for DISP index. We concludedthat two indices, supplemented with indicator valuesfor some local diatom species, can be a promising toolfor soda pan conservation in this part of the CarpathianBasin.