Ulansuhai Nur (Mongolian: Улан сухай нуур, meaning “Red Water Lake”) is a freshwater lake situated in the eastern part of the Inner Mongolia Autonomous Region of the People’s Republic of China. It is the largest natural lake in the region and lies near the city of Hohhot, the regional capital. The lake is part of the larger Hailar–Ulan‑Lake basin and is fed primarily by the Hailar River and several smaller tributaries.
Geography
- Location: Approximately 20 km southeast of Hohhot, spanning the districts of Xincheng and Huimin within the Hohhot municipality.
- Coordinates: Roughly 40°41′N 112°02′E.
- Surface area: Varies seasonally between about 150 km² in the dry season and up to 210 km² during periods of high precipitation.
- Maximum depth: Approximately 6 m, with an average depth of around 3 m.
- Elevation: About 1,050 m above sea level.
Hydrology
Ulansuhai Nur is a shallow, endorheic lake whose water balance is governed by inflow from the Hailar River, precipitation, and evaporation. Seasonal fluctuations are pronounced; water levels typically rise during the summer monsoon months (June–August) and recede during the winter when evaporation rates decline but inflow is reduced.
Ecology
The lake supports a variety of wetland habitats, including reed beds, marshes, and open water zones. Notable flora includes species of Phragmites australis (common reed) and Typha spp. (cattails). Faunal assemblages comprise:
- Fish: Indigenous species such as Cyprinus carpio (common carp) and Ctenopharyngodon idella (grass carp).
- Birds: The lake is an important stopover and breeding site for migratory waterfowl, including the Eurasian wigeon (Anas penelope), the black‑necked grebe (Podiceps nigricollis), and the white‑fronted goose (Anser albifrons).
- Mammals: Semi‑aquatic mammals such as the Eurasian otter (Lutra lutra) have been recorded in the surrounding wetlands.
Economic and Cultural Significance
Ulansuhai Nur provides water for agricultural irrigation, livestock watering, and domestic use for nearby settlements. The lake’s fishery sector contributes to local livelihoods, with annual catches reported in the low‑thousands of metric tonnes. Recreational activities, including birdwatching and limited tourism, have developed around the lake, particularly after the construction of a modest visitor center in the early 2010s.
The name “Ulansuhai” combines the Mongolian words ulan (“red”) and suhai (“water”), reflecting traditional observations of the lake’s occasional reddish tint caused by algal blooms.
Environmental Concerns
- Eutrophication: Agricultural runoff containing nitrogen and phosphorus has led to periodic algal blooms, reducing water clarity and oxygen levels.
- Water Level Decline: Over‑extraction for irrigation and prolonged drought periods have contributed to a gradual decline in lake surface area over the past two decades.
- Conservation Measures: In response, the Inner Mongolia government designated parts of the lake’s shoreline as a nature reserve in 2015, implementing monitoring programs for water quality and wildlife populations.
Research and Monitoring
Scientific studies conducted by the Inner Mongolia Academy of Sciences and regional universities have focused on hydrological modeling, biodiversity assessment, and the impacts of climate variability on lake dynamics. Data from these studies are incorporated into the national water resources monitoring network.
See also
- Hailar River
- Inner Mongolia wetlands
- Mongolia’s endorheic lake systems
This article reflects information compiled from Chinese geographic surveys, scientific publications, and regional environmental reports available up to 2024.