The Daurian forest-steppe is a mosaic of grass and forest that straddles the border between Russia and east-central Mongolia. The ecoregion includes a small part of China that supports sheep grass and needle thatch grassland in the Inner Mongolia Autonomous Region.
This ecoregion supports large rivers including the Onon and the Ulz. The average altitude of the mid-sized mountains reaches 1400-1800 m while the mean altitude of valleys is 1100-1200 m. Forest types found in this ecoregion include Siberian larch forest with numerous herb species, mixed forests of birch-pine and birch-larch trees, and birch and shrub forests. Aspen (Populus tremula) groves are found in marginal mountains. Steppe extends to the eastern part of the Khentii Mountain Ranges along the Onon-Balj River basins where larch, pine, and birch forest dominate not only hill slopes, but there are also pure pine forests along the sandy river valleys.
Flora of this area is composed of representative species of Daurian forest and mountain steppe, but Mongolian steppe species dominate in the south. Distributed throughout the region is a variety of grass associations such as Carex-Poaceae meadow steppe, Compositae-Gramineae-herbs steppe and sandy versions of saltmarsh-tussock steppe. Bordering these associations are halophytic meadows at lake edges. Also along the shores of the lakes are reed groves, groves of herbs, willow, and aspen (Populus tremula). Sedge-reed and sedge-halophytic herb marshes are found in low, wet depressions. The Red Data Book of Mongolia identifies a number of notable plant species in this ecoregion of which fifteen are considered very rare, four rare, eight endemic, and thirteen sub-endemic.
A large population of white-naped (Daurian) crane nests in wet areas of the steppes in the Ulz and Onon River valleys and in other valleys, which are important habitats for five other species of cranes as well.
Many species of fish and other aquatic species inhabit the Onon and Balj Rivers, including the Arctic lamprey eel (Lampetra japonica), Kaluga sturgeon (Huso dauricus), Khadary whitefish (Coregonus chadary), Haitej sculpin (Mesocottus haitej), Paracottus kessleri, river crayfish (Cambaroides dauricus), Dahurinaina dahurica, Rana chensinensi, and water snake (Natrix natrix).
Grasslands are rich in small mammals such as scilly shrew (Crocidura sauveolens), harvest mouse (Micromys minutus), long-tailed souslik (Citellus undulatus), Maximovich’s vole (Microtus maximowiczii), Daurian pika (Ochotona daurica), Tolai hare (Lepus tolai), a number of hamster species (Phodopus spp.), Daurian zokor (Myospalax aspalax) and Siberian marmot (Marmota sibirica). Predators include wolf (Canis lupus), fox (Vulpes vulpes), polecat (Vormela pereguzna), Eurasian badger (Meles meles), and Pallas’ cat (Otocolobus manul).
About 10 species of mammals such as musk deer, Siberian moose, Daurian hedge-hog, raccoon dog, lynx, as well as 10 species of birds including white-tailed sea-eagle (Haliaeetus albicilla), white-naped crane (Grus vipio), black stork (Ciconia nigra), whooper swan (Cygnus cygnus), swan goose (Anser cygnoides), Baikal teal (Anas formosa), and great bustard (Otis tarda) are registered in Mongolia’s Red Data Book and in the IUCN Redlist.
Detrimental human activities include unregulated road construction, unsustainable grazing practices, and illegal hunting. Increased frequency of droughts, human-induced water shortage, desertification, and wild fires are the most widespread and severe threats to these ecosystems.
The trans-boundary international protected-area network of Dauria interconnects forest steppe and steppe ecoregions. The forest steppe zone is protected by the forest-grassland fringe of Onon-Balj National Park and Ugtam Reserve in Mongolia in the west, and the mighty wetland delta of China's Erguna-Genhe Wetland Nature Reserve in the east. Marshes and reed beds provide breeding habitat for the great-crested grebe (Podiceps cristatus), and several species of crane. Two rare birds that breed on the adjoining plains are the great bustard (Otis tarda, IUCN Vulnerable) and Oriental plover (Charadrius veredus). In Aginsky-Buryatsky Autonomous Province of Russia Aginskaya steppe wildlife refuge is an important waterfowl habitat, while Alkhanai National Park is the best example of forested hilly landscapes and the most important sacred place for all Buriat Buddhists.
Onon River valley (Photo by Vadim Kiriliuk)