Wetlands in Sambhar Salt Lake

SAMBHAR, PHULERA, AND DIDWANA SALT LAKES - Rajasthan.

Location: approximately 60 km northwest of Jaipur, Rajasthan. Sambhar Lake lies west and northwest of Sambhar town, in Jaipur, Nagaur, and Ajmer Districts
Area: Sambhar 23,400 ha; Phulera 600 ha; Didwana 200 ha
Altitude: .365 m
Biogeographical province: 4.15.4 Wetland type: 09,16

Description of site: Sambhar Lake is the largest of these three saline wetlands, the most expansive inland saline depressions in India. The lake receives run-off from a catchment area of about 552,000 ha and has no outlet. Sambhar is fed by four main streams: Roopnagar, Mendha, Kharian, and Khandel. Phulera. (4 km south of Sambhar) and Didwana (60 km to the northwest) are considerably smaller. Sambhar and Phulera lie immediately east of the Aravalli Range which bisects eastern Rajathan. A number of small, shallow, brackishwater marshes are scattered around these saline lakes. Sambhar is surrounded by low hills and fossil dunes, with Sambhar town being located on one such dune. About 7800 ha of the eastern part of Sambhar Lake, north and west of Sambhar town, is devoted to salt production by Sambhar Salts Ltd, a Government of India company. About 200,000 - 250,000 metric tonnes of salt are produced annually. Similarly, approximately 20% of Didwana Lake is given over to salt pans. Sambhar Lake is skirted by the main Jaipur-Jodhpur railway. A 5.16-km long dam (Gudha Jhapog Dam), supporting a railway line used by the salt company, has been constructed through the lake, dividing it into two sections: the reservoir and salt-works, and the main lake. The area of flooding at each of the saline lakes depends upon the volume of monsoon rains, and the depth varies seasonally and from year to year from a few centimetres to a maximum of two metres. Sambhar Lake often dries out completely in early summer (March to June). Following the heavy monsoon rains of 1974, 1975, 1977, and 1980, the Lake retained water throughout the year, but in 1987, following four years of drought, it was completely dry by December. Rainfall was heavy during the monsoon of 1992 and Sambhar Lake had ample water during the winter of 1992-93, attracting large numbers of migratory waterfowl. Intense evaporation creates an extremely saline environment. All three lakes are surrounded by sandflats and dry thorn scrub.

Climatic conditions: Tropical monsoon climate with an average annual rainfall of about 500 mm. Summer temperatures range from 24.4°C to 36.7°C, winter temperatures from 11.7°C to 31.7°C

Principal vegetation: The most dominant algae in Sambhar Lake and the salt pans are Dunaliella saliva, Chlamydomonas sp., Anabaena sp., and Aphanothece halophytica. Most of the permanent vegetation around the Lake is xerophytic in nature. The main tree species growing in the catchment are Acacia Senegal (kumbhet), A.nilotica (babul), Salvadora oleoides, Capparis decidua, Prosopis cineraria, Maytenus emarginata, Azadirachta indica, Tecomella undulata, etc. Prosopis cinererea (Khejari) is the dominant tree in the sandy area. Anogeissus pendula, Euphorbia royleana, and Boswellia serrata are found growing on the nearby hills. The main shrub species are Tamarix dioica, Mimosa hamata, Acacia jacquemontii, Leptadenia pyrotechnics, and Calotropis procera. Other vegetation includes Saccharum bengalensis, S.spontaneum, Sericostema pauciflora, Crotolaria burhia, Tephrosia purpurea, Aerva persica, Tephrosia spp., and Portulaca oleracea . The main grasses are Cenchrus pennisetiformis, C.ciliaris, Chloris dolichostachya, Dactyloctenium aegyptium. Sporobolus sp., Aleuropus lagopoides, and Chloris virgata. The common ephemerals, which make their appearance after the first showers, are Farsetia hamiltonii, Indigofera cordifolia, Corchorus trilocularis, Portulaca oleracea, Trianthema portulacastrum, etc.

Land tenure: Sambhar Lake is state-owned. A part is leased out to the Sambhar Salts Ltd, a Government of India enterprise. The surrounding areas are partly state-owned and partly privately owned

Conservation measures taken: Sambhar Lake was declared a Ramsay Site in 1990. No habitat protection, but shooting is prohibited Conservation measures proposed: None

Land use: Extraction of salt is the only major activity. Domestic livestock graze in the areas, and marble is mined in the nearby hills. About 20 villages are located around Sambhar Lake. Extraction of salt from brine by private individuals is undertaken and some cultivation too

Disturbances and threats: Grazing pressure by cattle, sheep, goats, and camels in the catchment appears to be intense. Hunting of waterfowl by local communities is reported

Fauna: Taken together, the three lakes are probably the most important wintering area for flamingos in India outside the Rann of Kachchh. An estimated 50,000 flamingos were counted at Sambhar in the winter of 1982-83. A large number of ducks and shorebirds occur on passage and in winter. Thirteen species of ducks and 32 species of shorebirds have been recorded, the lakes being particularly important for Anas clypeata and Recurvirostra avosetta. Anser indicus is regularly present in winter in small flocks of up to 170 birds, and up to 150 A. anser have been observed at Phulera and Didwana A mixed flock (totalling approximately 15,000) of the following avifauna were observed at Sambhar Lake in January 1993: lesser flamingo, greater flamingo, tufted duck, pochard, white pelican, brown-headed gull, black-headed gull, herring gull, redshank, greenshank, common sandpiper, blackwinged stilt, pintail, shoveler, dabchick, purple moorhen, demoiselle crane, large Indian pratincole, and avocet. In addition, an estimated 4000 Phoenicopterus ruber and P.minor were observed at the reservoir adjoining the salt pans of Sambhar Lake Phulera Salt Lake is the wintering area fora variety of waterfowl, prominent among them (as recorded in January 1993) being Anser anser (15), Ciconia nigra (37), and several ducks and waders such as Tringa totanus (14 Around Phulera and Sambhar Lakes there are a number of brackishwater marshes that attract migratory waterfowl. The species identified at Mudia talab ackoining Phulera Lake in January 1993 were coot, pintail, pochard, gadwall, common teal, dabchick, red-shank, and brahminy duck. Two shallow brackishwater marshes adjacent to Sambhar Lake had a mixed flock (approximately 250) of garganey, wigeon, redshank, brown-headed gull, black-tailed godwit, pintail, common teal, large egret, little egret, coot, avocet, and large Indian pratincole Special floral values: The green alga Dunaliella saliva is an ecologically and economically interesting saline species Research and facilities: Some waterfowl surveys have been counducted at the lakes, and research on the geological and geomorphological processes of salt generation carried out. The Department of Zoology, University of Jodhpur, has studied the limnology of Sambhar and Didwana lakes. The Cetral Institute of Brackishwater Aquaculture, Madras, has surveyed the saline lakes of Rajasthan for the development of aquaculture