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Detecting the Spatial Distribution of Artemia at Urmiea Lake
Regarding the above table it seems that Urmia Artemia is a unique species totally different from others in terms of its biometric indices. Figure no. 1 shows a picture of Artemia Urmiana.  Fig 1: Picture of Artemia Urmiana (Female & Male) Artemia breeding happens in two different ways as bisexual and parthenogentic.In a normal condition where the degree of salinity is low (entrances of river and also in rainy seasons) artemia breeds as parthenogentic while under unfavorable condition with an increase in salinity (dry season and inside the lake) breeding occurs as bisexual. The two different breeding ways may occur in Urmia Lake however prominent breeding condition in Urmia Lake is bisexual due to salinity of the lake. Methodology Preliminary investigations disclosing distribution of artemia in the lake led to sampling methods. Samplings were done in a few points in the lake. Landsat TM images of 31-6-1989 were used to detect spatial distribution of artemia. Following flow chart shows different steps conducted in this study.  Fig 2: Research flowchart Multi-spectral ETM data enhances artemia in the lake specially using training samples collected throughout the lake. Contrast stretch techniques were applied when images were corrected for both geometric and radiometric errors. Colure composite images of 432 shows massive like distribution of artemia in the lake concentrated in a few portions throughout the lake.  Fig 3: Artemia distribution in Urmia Lake (Ghobadlu and north of Islamic Island) |