The Study of AnzaliWetland Potential for the Natural Growth of Astacus Leptodactylus by Using the Geographical Information System (GIS)

Due to the economic and currency importance of king prawn in the fresh water, an investigation was carried out in Anzali wetland to study the potential Habitat for the natural growth of Astacus Leptodactylus. The samples were selected from 13 station from inflow rivers (Behamberoud, Morghak, and Khalkayi, Spand, Koulehsar, Chomestghal, Nargestan, Siadarvishan, Hendekhaleh, Pirbazar, Bigroud, Ghanadi, Ramezan Bekandeh, Sheyjan). The superficial water samples were prepared by Nansen bottle, and were prepared according to the APHA standard method to determine their physiochemical parameters. To determine the parameters of BOD, Calcium, total Phosphor, total hardness and NH4, the Standard Method for Water and waste Analysis was used. The results showed that the average temperature ranged from 18.39 to 19.25oc, and the mean minimum and maximum oxygen solution changed between 6.28 and 6.9 (ppm) in stations 1 to 13, and these amounts were in proportion to the best needs of this type. Also the amount of Calcium, the most important factor for the growth of this type, ranged between 58.29 to 67.93 in 13 stations, and these amounts were ideal, and Calcium did not seem to be a limiting factor for the growth of king prawns in Anzali wetland. The king prawns had a good survival and physiological capacity in PH between 6.5 to 8, and these amounts were in proportion to the mean values ranging from 7.28 to 7.87 obtained from the stations in questions. It can be stated that the most effective factors in reducing the reservoirs of king prawns of Anzali wetland were the increased rate of water pollution, diseases, and probably recent droughts, the immigration of Macrobroachyim and Azola, the release of fish cubs called Zander, the increased number of hunters, the reduction of average depth of wetland, sedimentation and retention times of salinity in this Habitat, especially during the past two years.