Regeneration of threatened alkali steppe vegetation after a heavy disturbance by disk tillage

Abstract

Several methods of tillage are among the practices most destructive to inland saline grasslands, and can result in their complete deterioration. Despite the high frequency of habitat destruction by these means, the recovery of the saline vegetation and regeneration abilities of halophytes are still not sufficiently known. The reaction of inland saline grasslands to disk tillage was studied on the Jatov site located in the Pannonian bioregion of Central Europe. Changes in species composition were tested using ordination methods (DCA, CCA). Although the species composition recovered to a certain extent after the 4 years following the disturbance, the original zonation of halophytic vegetation was disturbed and did not recover. Disturbance primarily suppressed perennial halophytes and promoted the occurrence of species with a ruderal strategy. Testing of halophyte reaction to tillage showed the contracting responses of various halophytic species. The species Atriplex littoralis, Plantago maritima and Matricaria recutita reacted positively to tillage due to the reduced competition. The species Artemisia santonicum subsp. patens and Dichodon viscidum were suppressed by tillage in initial stages, but later recovered their populations. Only A. santonicum subsp. patens was able to return to the abundance seen before the disturbance. The only halophytic species which was unable to recover was a shallow-rooted grass Puccinellia distans. Our study showed that a Pannonian alkali steppe is able to recover quite quickly after tillage, if the soil disturbance is shallow and subsequent management takes place. Some halophytes may even profit for a short time from tillage, but the original species composition cannot be restored in the short term.