Sunday 26 September 2021

Grassland restoration on kurgans in the Hortobágy National Park

Kurgans (ancient burial mounds built by nomadic steppic tribes) are iconic landmarks that are included in the European Landscape Convention as features characteristic of the Hungarian landscape. To maintain and highlight their landscape values, in many cases, active restoration actions are necessary. On mounds formerly ploughed or degraded, grassland restoration is a good option to increase the conservation values. This way, weed suppression and the establishment of target grassland species can be supported in a cost-effective way. Suppression of weeds can increase the landscape value of the kurgans and is also beneficial for the farmers as the suppression of weeds on the kurgan also decreases the amount of weeds in the neighbouring croplands. The established grassland species can increase the landscape-scale biodiversity, and the restored grassland patches can be essential elements of the landscape-scale network of semi-natural habitats.


The restoration team: Károly Hoffmann, Balázs Deák, Sándor Újfalusi, Sándor Borza, Orsolya Valkó, Laura Godó, Réka Kiss; and of course Fidó dog:)


Our research group, together with the colleagues of the Hortobágy National Park Directorate aimed to restore the grassland vegetation of three kurgans.

In the Álom-zug, we restored a 0.7-hectare-sized area  by sowing seeds of a fescue species (Festuca rupicola) characteristic of the loess grasslands of the region, in a density of 25 kg/ha. To make sure that the seeds are sown in the most homogeneous way, we broadcasted the seeds from two pickups that were moving in parallel. This enabled a precision sowing and gave us a very funny experience  :) 

We divided the seeds to fix portions for each sector, to make the sowing as homogeneous as possible.

Seeds of Festuca rupicola.

Measuring the portions.

We could broadcast the seeds homogeneously from the two pickups.

We also did magic :)

Seed rain :)
 
On all the three mounds we also introduced grassland specialist species by directed seeding. For this we used the soil disturbances available on the sites, e.g. fox burrows or wild boar rootings. Agropyron cristatum was sown on the top of the mounds, since in natural conditions this species often forms monodominant patches in this micro-habitat. The forb species were sown as a seed mixture into the open patches on the slopes. The seeds of forbs were collected by our research group and by the Hortobágy National Park Directorate. We used the seeds of the following species characteristic of loess grasslands: Achillea collina, Centaurea pannonica, Dianthus pontederae, Galium verum, Hypericum perforatum, Knautia arvensis, Phlomis tuberosa, Salvia austriaca, Salvia nemorosa, Scabiosa ochroleuca, Silene vulgaris and Verbascum phoeniceum. We hope that these species can establish successfully in the establishment gaps, and later they can be abundant on the kurgans.
 
Mixing of the forb seeds with soil.

 
Soil preparation by hoeing.
 
 
Soil preparation by raking.

 
Sowing of the diverse seed mixture.