LAKE HUBSUGUL

A view on the lakeshore


Photo: P.Nyamjav

A. LOCATION

• Hubsugul Aimag, Mongolia.
• 50:27-51:37N, 100:51-101:47E; 1,645 m above sea level.

B. DESCRIPTION

Lake Hubsugul is the largest freshwater lake in Central Asia. The landscape complex around the lake is unique and inimitable in its beauty. The lake basin consists largely of highlands, where underground permafrost layers, sometimes as deep as 100-200 m, are widespread.
The climate is severely continental with 300-430 mm of mean annual precipitation. Between the lake shore and the top of high mountains reaching 3,491 m in altitude, there is a series of alternating vegetation zones from steppe, through forest-steppe, forest and forest-tundra, to alpine tundra zone. Forests of larch, cedar, pine and birch predominate on permafrost, together with tundra. The lake basin supports 60 species of mammals including 32 game animals and 800 species of plants of which more than 50% are grasses and herbs.
The lake has three tributaries, while a single river, the Egyn-gol flows out toward Lake Baikal. There are petroleum fields in Hatafal and Hanh on the north and the south side of the lake. More than 30 phosphorite beds have also been exploited.
It is of prime importance for this lake as a natural treasure how to maintain its crystal-clean water against the impact from industrial developments. The exploitation of phosphorite beds may disrupt surrounding environments, Lake Hubsugul, and eventually Lake Baikal via the Egyn. Local authorities are making efforts to cope with the problem, but the processes and extent of industrial influence on the environment still remain unknown because of the lack of comprehensive ecological research on the complex system of the lake, its surroundings, rivers and springs (Q1).

C. PHYSICAL DIMENSIONS (Q1, 2)

Surface area [km2]	2,770
Volume [km3]	381
Maximum depth [m]	267
Mean depth [m]	138
Water level	Unregulated
Normal range of annual water level fluctuation [m]	0.5-2.0
Length of shoreline [km]	414
Catchment area [km2]	4,940

D. PHYSIOGRAPHIC FEATURES (Q1)

D1 GEOGRAPHICAL

• Bathymetric map: Fig. ASI-51-01.
• Names of main islands: Modon Khui and Khadan Khui.
• Number of outflowing rivers and channels (name): 1 (Egyn-gol).

D2 CLIMATIC

• Climatic data at Hatgal, 1980-1989

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Ann.
Mean temp. [deg C]*1	-22.7	-21.2	-13.1	-2.5	5.5	9.2	11.4	10.4	4.6	-3.8	-14.2	-20.4	-4.8
Precipitation [mm]*2	0.8	0.3	2	8	17	77	90	71	31	11	10	0.4	319

*1 1980-1989. *2 1980-1986.

• Number of hours of bright sunshine: 2,773 hr yr-1.

Fig. ASI-51-01
Bathymetric map [m](Q1).

• Water temperature [deg C]

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
0.5	-	-	-	-	5.1	9.9	13.4	13.6	9.5	3.8	-	-

• Freezing period: ca. 15 June-25 October.

E. LAKE WATER QUALITY (Q1)

E1 TRANSPARENCY [m]

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
	30	30	-	-	-	-	19	13	24	-	30	30

E2 pH

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Station 1, Hatgal, 1986-1990
0.5	7.9	7.6	7.8	7.4	6.9	7.9	7.9	7.9	8.0	7.8	8.0	7.6
Station 2, Hanh, 1986-1990
0.5	7.9	7.9	8.0	7.5	7.6	8.2	7.4	7.9	7.7	7.5	8.1	7.8

E4 DO [mg l-1]

Hanh, 1986
Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
0.5	7.7	7.7	10.3	10.9	8.4	7.0	9.0	8.3	9.4	-	-	-

E5 COD [mg l-1]

Determined by KMnO4 method.
Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Station 1, 1986-1990
0.5	1.1	2.7	2.3	2.1	0.9	2.1	1.8	3.1	1.9	2.7	2.4	1.5
Station 2, 1986-1990
0.5	1.4	2.0	3.2	1.8	1.5	3.7	2.2	1.5	3.3	1.4	2.2	2.6

E6 CHLOROPHYLL CONCENTRATION

The content of chlorophyll a of the lake water is very low, being 0.35 micro l-1 in average for the layer of 0-100 m.

E7 NITROGEN CONCENTRATION

• NO3-N [mg l-1]

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Station 1, 1986-1990
0.5	0.05	0.19	0.17	0.32	0.12	0.19	0.20	0.22	0.08	0.11	0.06	0.02
Station 2, 1986-1990
0.5	0.18	0.20	0.27	0.10	0.11	0.19	0.67	0.10	0.10	0.21	0.05	0.02

• NH4-N [mg l-1]

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Station 1, 1986-1990
0.5	0.14	0.16	0.14	0.21	0.16	0.05	0.18	0.30	0.15	0.04	0.10	0.11
Station 2, 1986-1990
0.5	0.11	0.14	0.18	0.13	0.28	0.19	0.24	0.14	0.14	0.04	0.08	0.08

E8 PHOSPHORUS CONCENTRATION

• Total-P [micro g l-1]

Depth [m]	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Station 1, 1986-1990
0.5	46	12	14	4	8	5	7	13	20	15	8	7
Station 2, 1986-1990
0.5	14	2	9	9	6	18	18	4	16	11	23	9

Fig. ASI-51-02
Seasonal change of PO4-P concentration [mg l-1] of surface water (Q1).

E10 PAST TRENDS

Fig. ASI-51-03
Long time fluctuation of PO4-P concentration [mg l-1] of surface water (Q1).

F. BIOLOGICAL FEATURES

F1 FLORA (6)

There are 55 species of floating aquatic plant, 33 species of submerged macrophyte, 2 species of moss and about 10 species of phytoplankton in the lake.

• Emerged macrophytes: Poaceae, Asteraceae, Cyperaceae (Q2).
• Phytoplankton (Q2)
  Cyclotella ocellata, Gymnodinium fuscum, Oocystis sobitaria, O. mongolica, Dictyosphaerium pulchellum, Chroomonas sp., Crucigenia quadrata, Glenodinium sp.

F2 FAUNA (Q2, 6)

• Zooplankton
  Mixodiaptomus incrassatus, Cyclops abyssorum, Daphnia longispina hyalina, Kellicottia longispina, Filinia longiseta, Conochilus unicornis (total 69 species).
• Benthos
  Hydra, Phabdococcida, Planaridae, Nematoda, Oligochaeta, Ostracoda, Gammaridae (total 170 species).
• Fish
  Brachymystax lenok, Coregonus autumnalis migratorius, Thymallus arcticus, T. nigrescens, Rutilus lacustris, Lota vulgaris, Lota lota, Perca fluviatilis (total 9 species).

F4 BIOMASS

• Phytoplankton (8)

Whole lake
	No. of samples	No. [1,000 l-1] Mean (range)	Biomass [mg m-3] Mean (range)
Jun.-Aug. 1972	50	812 (355-1,650)	166 (64-301)
Mar. 1973	21	1,399 (99-2,806)	212 (22-453)

Pelagic water, Hanh region (Q1)
Date		Biomass [mg m-3]
		Cyclotella ocellata	Dictyosphaerium pulchellum	Total
1976	Jun. 16	17	61	113
	Jul. 8	30	58	135
	Jul. 20	46	31	179
	Jul. 29	57	28	140
	Aug. 9	92	33	172
	Aug. 20	96	34	204
	Sep. 18	67	2	95
	Sep. 25	104	2	140
	Oct. 21	37	7	81
	Dec. 22	160	25	226
1977	Feb. 28	36	25	85
	Mar. 21	36	57	137
	Mar. 27	50	73	173
	May. 13	22	78	144
Mean		61	37	145

Fig. ASI-51-04
Vertical and horizontal distribution of phytoplankton biomass in pelagic water, March 1973 (Q1).

• Zooplankton (9)

Whole lake survey
Date	No. of samples	Mean No. (range)[1,000 l-1]
		Copepoda	Cladocera	Rotatoria	Total
Jun.-Aug. 1978	18	9.2 (1.7-21.6)	0.66 (0.1-2.4)	0.32 (0.1-0.9)	10.1 (1.9-22.4)
Jul. 1979	9	8.3 (5.1-10.1)	0.44 (0.1-0.7)	0.54 (0.1-1.1)	9.3 (5.8-11.4)

Date	No. of samples	Mean No. (range)[mg m-3]
		Copepoda	Cladocera	Rotatoria	Total
Jun. -Aug. 1978	18	158.2 (11.4-362.0)	11.0 (0.3-34.6)	0.31 (0.1-1.0)	168.4 (11.8-373.4)
Jul. 1979	9	183.6 (78.0-283.0)	8.0 (3.0-16.0)	0.69 (0.1-1.0)	192.2 (82.0-299.2)

• Zoobenthos (8)

Whole lake survey
Zone (depth)	Mean No. [m-2]	Mean biomass [g m-2]
Open water
- Littoral (0-20 m)	4,304	4.8
- Sublittoral (20-50 m)	4,267	5.4
- Upper abyssal (50-90 m)	1.322	0.8
- Lower abyssal (>90 m)	303	0.2
Bays
- Alagasair	7,190	4.5
- Turugsky	5,350	6.5
- Khankhinsky	10,862	3.8
- Mongorinsky	5,903	10.3

Hanh region
Date	No. of samples	No. [m-2]	Biomass [g m-2]
Aug. 1971	6	2,399	1.8
Jun. 1972	15	7,570	3.8
Jul. 1976	2	9.570	5.7
Aug. 1976	8	8,053	2.7
Sep. 1976	4	5,252	1.8

• Total biomass of the whole lake system (Q)

Zone		[g m-3]	[g m-2]	[1,000 t/zone]
Littoral & sublittoral (15% of total lake area)	Phytobenthos	-	0.6-3.5
	Zoobenthos	-	5.0	2,070
Abyssal (85%)	Zoobenthos	-	0.5	1,173
Whole water column	Bacterioplankton	0.03	3.48	9,605
Photic zone (mean depth 16 m)	Phytoplankton	0.17	19.72	54,427
	Zooplankton	0.10	11.60	32,016

F5 FISHERY PRODUCTS (6)

• Annual fish catch [metric tons]
  
  1990: 300.

G. SOCIO-ECONOMIC CONDITIONS

G1 LAND USE IN THE CATCHMENT AREA

	Area [km2](Q1)	[%](Q2)
Natural landscape
- Woody vegetation	-	30-60
- Herbaceous vegetation	-	20-30
- Swamp	-	5-10
- Others	-	5-10
Agricultural land
- Crop field	(9.2)
- Pasture land	2.7	25-30
Residential area	6.5
Total	4,920	100

• Types of important forest vegetation (Q1, Q2)
  Larix sibirica and Betula platyphylla, with Lonicera altaica, Ledum palustre, Vaccinium vitis-idaea, Calamagrostis obtusata, Aconitum septentrionale, Hylocomium proliferum, etc.
• Types of other important vegetation (Q1, Q2)
  High mountain lichen-moss tundra (Cladonia alpestris, Cetraria cuculata).
• Main kinds of crops: No crop field.

G2 INDUSTRIES IN THE CATCHMENT AREA AND THE LAKE

• Numbers of domestic animals in the catchment area (Q2)
  Cattle 8,466, sheep 6,650, others 1,434.

G3 POPULATION IN THE CATCHMENT AREA (Q1)

1990
	Population	Population density [km-2]	Major cities (population)
Urban	5,473	-
Rural	1,163	-	Hatgal
Total	6,636	1.3

H. LAKE UTILIZATION

H1 LAKE UTILIZATION (Q1)

Source of water, navigation and transportation (20,000-30,000 tons of cargo per year during 1953-1990; it will be stopped in the second half of 1991), sightseeing and recreation.

H2 THE LAKE AS WATER RESOURCE (Q1)

Use rate of domestic water: 1.43 [m3 sec-1].

I. DETERIORATION OF LAKE ENVIRONMENTS AND HAZARDS (Q2)

I1 ENHANCED SILTATION: None. I2 TOXIC CONTAMINATION

• Present status: None.

I4 ACIDIFICATION

• Extent of damage: None.

J. WASTEWATER TREATMENTS (Q2)

J1 GENERATION OF POLLUTANTS IN THE CATCHMENT AREA

b) No sources of significant pollution.

M. LEGISLATIVE AND INSTITUTIONAL MEASURES FOR UPGRADING LAKE ENVIRONMENTS (Q1)

M1 NATIONAL AND LOCAL LAWS CONCERNED

The Government had closed the wool-washing factory from July 1988, and also has decided to remove the petroleum reserve to Muren town within 1991.

M2 INSTITUTIONAL MEASURES

1. Hubsugul Lake Protection Foundation

M3 RESEARCH INSTITUTES ENGAGED IN THE LAKE ENVIRONMENT STUDIES

1. The administration for the Hubsugul Lake protection.
2. Soviet Union and Mongol joint expeditions for the Hubsugul Lake study.

N. SOURCES OF DATA

17. Questionnaire filled by Dr. P. Nyamjav, Head, Surface Water Resource Sector, State Committee for Environmental Control Institute of Water Problems, Ulaanbaatar, Mongolia. (Q1)
17. Questionnaire filled by Mr. Ts. Baldorj, Newspaper of the MPR Government (UNEN), Ulaanbaatar, Mongolia. (Q2)
1. Tserensodnom, J. (1970) Lakes of Mongolia. Ulaanbaatar.
2. Dulmaa, A. (1985) Life in the Lake. Ulaanbaatar.
3. Gira, E. (1985) Climatic Reference Book of the MPR. Vol. 1, Solar Energy Cadastre. Ulaanbaatar.
4. Erbaev, E. A. & Kojova, 0. M. (1990) The problems of zoobenthos study of the Hubsugul Lake. Natural condition and resources of some regions of the MPR. Theses of the talks and conferences, XVII International Scientific Conference on the Results of the Mongolian and the Soviet Union Complex Expedition Work of the Hubsugul Lake.
5. Dulmaa, A. & Tserensambuu, S. (1990) General Estimation of Primary Productivity of the MPR's Lakes. Ulaanbaatar.
6. --- & --- (1990) The Hubsugul Lake monitoring. "Problems of Nature and Environmental Protection of the Hubsugul Lake and the Selenge River Basins." Ulaanbaatar.
7. Kojova, 0. M. & Zagorencko, G. F. (1976) Winter phytoplankton of the Hubsugul Lake. "Natural Condition and Resources of Prikhubsugul, Proceedings of the USSR and MPR Complex Expedition of the Hubsugul", Issue 3-4. Irkutsk-Ulaanbaatar.
8. Kojova, 0. M., Zagorencko, G. E., Pomazkova, G. I., Putyatina, T. N., Erbaev, E. A. & Izmesteva, L. R. (1978) Hydrological regime of the Hubsugul Lake. "Hydrobiological and Ichtiological Studies in the East Siberia." Irkutsk.
9. Pomazkova, G. I. & Shyagina, E. V. (1982) Distribution of zooplankton in the Hubsugul Lake in summer, 1978-1979. "Natural Condition and Resources of Prikhubsugul, The Proceedings of the Research Talks, ISU, MSU."
10. Tsengel, T. (1990) The principal characteristics of the Hubsugul Lake. "Problems of Nature and Environment Protection of the Hubsugul Lake and the Selenge River Basins, The Proceedings of the Research Conference." Ulaanbaatar.