Kurgans – linkage between biodiversity protection and history

Species-rich dry grassland fragments on ancient burial mounds (kurgans) are my primary and favourite research objects. Kurgans are one of the most iconic landscape elements of the Eurasian steppes. They are ancient burial mounds - dating back even to the Eneolithics - of already disappeared cultures such as the Yamnajas, Schitians, Sarmathians. The first kurgans of the Carpathian Basin were built between 3,300-2,500 BC; thus, even it is not obvious for the first sight kurgans have the same age as pyramids of Egypt (the Great Pyramid of Giza was built under the reign of Khufu between 2,580-2,530).

Most of the kurgans were built from the topsoil of the neighbouring areas, which was piled upon a central pit grave. Their height ranges between 0.5 to 15 metres and their area is generally less than one hectare. First we made a comprehensive review on the distribution, vegetation, land use and threatening factors of the kurgans in Eurasia (Deák et al. 2016 Biodiversity and Conservation). We estimated based on the available literature and existing databases, that there are approximately 600,000 kurgans in the Eurasian steppes and they are widely distributed from Hungary to Mongolia. Even though many kurgans have been raided during the past Millennia, they still hide many interesting archaeological artefacts that can contribute to the understanding of our history. Also the kurgans have important cultural values, they act as sacral places and have an important role in the local folklore (there are many tales and sagas about the kurgans).

The Filagória-kurgan functioning as a demonstration site at the Hortobágy National Park, Hungary.

The reason why kurgans are really interesting objects for ecologists is their special flora and fauna. That is why in the past four years we sampled the vegetation, arthropod assemblages, habitat quality and landscape context of 168 kurgans in Hungary.

Map of the surveyed kurgans

Besides their cultural and historical importance kurgans also have outstanding conservational values. In the intensively used agricultural landscapes kurgans preserving grassland habitats can act as habitat islands for many grassland species (see the papers Deák et al. 2016 Biological Conservation and Deák et al. 2018 Landscape Ecology). The reason for that in many cases even in highly transformed landscapes grassland vegetation of kurgans remained intact due to the respect of historical and cultural values. And well, we have to admit: the steep slopes of the kurgans (which is difficult to plough) also contributed to their undisturbed state in many cases. In some other cases there were some administrative reasons for the conservation of the kurgans. Even during the medieval, city borders were fitted on the location of the kurgans, as they were fix and well visible points in the flat plains. The land use intensity on such kurgans were lower than in the neighbouring areas. The situation is the same with the kurgans located on the borderland of countries. One can find extremely diverse and well preserved loess grassland vegetation in the borderland between Hungary and Romania.

Species rich grassland preserved on the Tatár-kurgan, located in the borderland between Hungary and Romania

In Hungary the kurgans with a natural vegetation predominantly harbour loess, alkali or sand grasslands. These grasslands even being small in their area harbour a lot of protected and regionally rare species. These species were formerly widespread in the landscape but due to the high level of landscape transformation and loss of grassland habitats, they become endangered. Such species are the crested wheatgrass (Agropyron cristatum), Jerusalem sage (Phlomis tuberosa) and the dwarf feather grass (Stipa capillata).

A typical species of the kurgan habitats, the protected Phlomis tuberosa

A good example for the biodiversity potential of the kurgans is the seven metres tall Mondró-kurgan, which is located near the village of Hencida (N 47.222028° / E 21.738456°). Even though the kurgan has been surrounded by arable lands at the time of the Second Military Survey of the Austrian-Hungarian Monarchy (1806-1869), during our visit on the kurgan we found several rare grassland specialist species in its small (40 x 60 metres) isolated grassland (Deák et al. 2015 Kitaibelia). The most interesting species were Inula germanica, Ranunculus illyricus, Aster sedifolius and Rosa gallica. Unfortunately, the encroachment of the woody species threatens the existence of the loess grassland of the kurgan, and thus the existence of the rare species. 

The loess grassland of the Mondró-kurgan with several thousands of Inula germanica.

Literature

Deák, B., Valkó, O., Török, P., Kelemen, A., Bede, Á., Csathó, A.I., Tóthmérész, B. (2018): Landscape and habitat and filters jointly drive richness and abundance of grassland specialist plants in terrestrial habitat islands. Landscape Ecology 33: 1117-1132. doi: 10.1007/s10980-018-0660-x PDF

Deák B., Valkó O., Török P., Tóthmérész B. (2016): Factors threatening grassland specialist plants - A multi-proxy study on the vegetation of isolated grasslands. Biological Conservation 204: 255-262.  PDF

Deák, B., Tóthmérész, B., Valkó, O., Sudnik-Wójcikowska, B., Bragina, T.-M., Moysiyenko, I., Apostolova, I., Bykov, N., Dembicz, I., Török, P. (2016): Cultural monuments and nature conservation: The role of kurgans in maintaining steppe vegetation. Biodiversity & Conservation 25: 2473-2490. PDF

Deák, B., Török, P., Tóthmérész, B., Valkó, O. (2015): Mondró-halom kurgan (Hencida, East Hungary), a refugium of loess grassland vegetation. Kitaibelia 20: 143-149. PDF