Definition
The Ulma is a river in Mazanovsky District, Amur Oblast, Russia. It is the longest tributary of the Selemdzha River.
Overview
The Ulma originates on the western slopes of the Turan Range at the confluence of its two headwaters, the Right Ulma and the Left Ulma (also called the Bordak). Flowing generally southwest in its upper reaches, then turning northwest and west across a marshy floodplain, it joins the left bank of the Selemdzha near the villages of Uglovoye and Bogoslovka. The river runs through a sparsely populated area, with the settlement of Ulma situated on its banks. It is noted as a destination for rafting and fishing.
Etymology / Origin
The origin of the name “Ulma” is not definitively documented in publicly available sources. Accurate information is not confirmed.
Characteristics
- Length: 346 km (215 mi)
- Drainage basin: 5 550 km² (2 140 mi²) – fourth largest in the Selemdzha basin after the Orlovka and Byssa rivers.
- Source elevation: approximately 480 m (1 570 ft) in the Turan Range.
- Mouth elevation: approximately 171 m (561 ft) where it enters the Selemdzha.
- Hydrology: The basin is primarily rain‑fed; about 90 % of annual runoff occurs during spring and summer. Flooding is common in spring, summer, and autumn. The river freezes from late October–early November until late April–early May.
- Tributaries: The most significant tributary is the 111 km long Kera River on the right bank; other tributaries are comparatively short.
- Flora and fauna: The Ulma supports a variety of fish species, including taimen, lenok, grayling, crucian carp, pike, burbot, and Amur catfish.
- Protected areas: The Ulma Zakaznik, a nature reserve of about 189 100 ha (467 000 ac), was established in 1981 to protect the middle basin’s ecosystems.
Related Topics
- Selemdzha River (receiving watercourse)
- Zeya River (downstream of the Selemdzha)
- Amur River basin (overall watershed)
- Turan Range (source region)
- Paleolithic Selemdzha culture (archaeological findings at Ust‑Ulma‑1)
- List of rivers of Russia
- Protected areas of Amur Oblast (including Ulma Zakaznik)