Background: Burial mounds (kurgans) of Eurasian steppes are man-made habitat islands that have the potential to harbour rich plant diversity due to micro-habitats associated with their topography. Aims: We assessed whether kurgan micro-habitats harboured different species pools and functional groups from those found on the surrounding steppes. In addition, we asked if these mounds were affected by different grazing intensities from those on the surrounding vegetation. Methods: We surveyed kurgan micro-habitats (northern and southern slopes, surrounding ditch) and adjacent steppe plains in non-grazed, moderately grazed and heavily grazed sites in northern Kazakhstan. We analysed differences in species composition of four habitats under three grazing regimes using Generalised Linear Mixed Models, PCA ordination and indicator species analysis. Results: Kurgan micro-habitats had diverse vegetation and supported the co-existence of plant species with different environmental needs. We identified 16 steppe specialists confined to kurgan micro-habitats. Steppe vegetation was well-adapted to extensive grazing, although heavy grazing supported ruderals and a decline in steppe specialists. There was a significant interaction between grazing intensity and habitat type: heavy grazing supported ruderals and suppressed steppe specialists especially on the slopes. Conclusions: We highlighted that kurgans play an important role as maintaining high plant diversity locally in extensive steppe plains in Central-Asia by increasing environmental heterogeneity and supporting specialist species confined to these micro-habitats.

Identification of variation in pasture use by domesticated livestock has important implications for understanding the scale of animal husbandry and landscape use in modern and ancient societies alike. Here, we explore the influence of pasture floral composition, salinity, and water availability on the carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopic composition of plants from the steppes of Kazakhstan. Our findings demonstrate geospatially defined differences in the isotopic composition of sedge marshes, saline marshes, and meadow steppes, information which we then use to inform animal management strategies used in the past. We then examine pasture usage by ancient livestock through carbon and nitrogen isotope analyses of bone collagen from animals that grazed in the northern Kazakh steppe. Pasturing strategies varied according to livestock taxa, with horses exhibiting lower δ¹³C and δ¹⁵N values relative to cattle, sheep, and goat. We argue that horses, which are highly mobile and freely graze over pastures extending over wide areas, were grazed under an extensive pasturing system. These data suggest that the isotopic composition of contemporary vegetation communities can help inform animal management strategies used in the past.