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Abstract

Vlaams Instituut voor de Tm Flanders Marine Institute L a k e U rm iah is a larg e (to tal su rfac e 4 7 5 0-6 1 0 0 k m 2 in re c e n t tim e s) th a la sso h a lin e h y p e rs a lin e lak e (1 5 0-1 8 0 g I-1 in th e p e rio d 1 9 9 4-1 9 9 6), lo c a te d in n o rth w e s te rn Iran. It is th e h a b ita t o f th e e n d e m ic A rte m ia u rm ia n a. O v er th e p e rio d Ju ly 1 9 9 4-J a n u a ry 1996 a sa m p lin g c a m p a ig n w as o rg a n iz e d : 3 6 fixed sa m p lin g sta tio n s, d istrib u ted o v e r th e e n tire la k e 's area , w e re sam p le d w ee k ly to d e te rm in e w a te r te m p e ra tu re , sa lin ity a n d tra n sp a re n c y. A t e a c h o c c a sio n a filter n et w as d ra g g e d o v e r a d is ta n c e o f 4 0 0 m in th e su p erficia l w ater la y e r to a sse ss th e d en sity a n d c o m p o s itio n o f th e A rte m ia p o p u la tio n. A m o re lim ite d sa m p lin g c a m p a ig n fo c u se d on th e a n n u a l flu ctu atio n s in c h lo ro p h y ll c o n c e n tra tio n and on th e re p ro d u c tiv e b e h a v io u r o f th e b rin e sh rim p p o p u la tio n. S ev eral stag es o f b rin e sh rim p su rv iv ed d u rin g w in te r m o n th s (w a te r te m p e ra tu re 3 C) at lo w d en sities. C o m p a re d to av ailab le d a ta fo r th e G re a t S alt L ak e, U S A , L ak e U rm ia h sh o w s a lo w alg al b io m a ss a n d o v erall low A rte m ia d en sity. The in c re a sin g g ra z in g p re ssu re o f th e d e v e lo p in g b rin e sh rim p p o p u la tio n in sp rin g seem s to p re v e n t th e p h y to p la n k to n fro m re a c h in g h ig h b lo o m in g c o n c e n tra tio n s, a n d o v ip a rity is th e d o m in a n t re p ro d u c tiv e m o d e th ro u g h o u t the re p ro d u c tiv e seaso n .

Coexistence of Sexual and Parthenogenetic Artemia Populations in Lake Urmia and Neighbouring Lagoons

“…We conclude that previous studies (CLARK and BOWEN, 1976;BADARACCO et al, 1987;BARIGOZZI et al, 1987;AZARI TAKAMI, 1989;AHMADI et al, 1990;BROWNE et al, 1991;PADOR, 1995;VAN STAPPEN et al, 2001) were correct in their findings about the Artemia population from Lake Urmia; namely, that different batches of cysts originating from different parts of either the lake or the neighbouring lagoons could have led to contradictory conclusions concerning the sexual status of the populations. On the basis of our results, we can assume that BADARACCO et al (1987) and BARIGOZZI et al (1987) used cysts produced in the lagoons adjacent to the lake or harvested from the coastal areas (some of the lagoons occasionally merge with the lake).…”

The impact of one-decade ecological disturbance on genetic changes: a study on the brine shrimpArtemia urmianafrom Urmia Lake, Iran

“…Urmia Lake (37°42′N, 45°19′E) is a landlocked thalassohaline lake with oligotrophic characteristics located in Northwest Iran. Its historical water surface area has ranged from 4,750 to 6,100 km 2 with the average and greatest recorded depths being 6 and 16 m, respectively (Azari Takami, 1993; Van Stappen, Fayazi & Sorgeloos, 2001). It is among the largest hypersaline lakes in the world, like Great Salt Lake, USA, which has an average surface area from 4,400 to 8,500 km 2 (Abatzopoulos et al, 2006; USGS, 2013), and it is inhabited by the brine shrimp Artemia urmiana Günther, 1899.…”

Water-Level Fluctuations of Urmia Lake: Relationship with the Long-Term Changes of Meteorological Variables (Solutions for Water-Crisis Management in Urmia Lake Basin)

“…Urmia Lake, located in northwestern of Iran in a geographic position between 45˚E -46˚E and 37˚4'N -38˚17'N, is an oligotrophic lake of thalassohaline origin with a total surface area between 4750 and 6100 km 2 and a maximum depth of 16 m at an altitude of 1250 m [14]- [16] (Figure 4). The total catchment area of the lake is about 51,876 Km 2 which is 3.15% of that of the entire country, and includes 7% of the total surface water in Iran.…”