Hydrological and Hydrobilogical study in the Persian Gulf (Khuzestan province water)

Abstract

This study was carried out in North of Persian Gulf from 2001 to 2002. Sampling was done in two transect (6 stations) in different depth in Khuzestan coastal waters. Some environmental parameters such as temperature, salinity, pH, DO, density, EC and chlorophyll a by CTD instrument and also Nutrient were measured. Phytoplankton was collected with Niskin sampler from 4 layers 0.5, 20, 50 meter and 2 meter above the bottom. Zooplankton and benthic fauna sampled by Pump and Peterson grab respectively. Physical and chemical parameters were showed little fluctuation during the year. The highest variation ranges were observed in: temperature (17.7-33.8), pH (5.3 - 7.2), DO mg/lit (2.9 -7.5), turbidity (3.8-16.3), salinity (39.4-40.9). The most frequent phytoplankton was observed in classes of: Bacilariophyceae (62%), Cyanophyceae (29%), and Dinophyceae (16%).The most frequent genus of each phytoplankton group were Rhizosolenia, Nitzschia, and Pluerosigma. Occurrence of phytoplankton decreased from surface water to depth layers and then increased near the bottom. The highest diversity and evenness indexes were in spring, summer and winter respectively. The most abundant of zooplankton were founded 5 groups included: Crustacean, moullsca and polycheata larvae, protozoa and some a few Chaetognaths. The most frequent groups of zooplankton were Copepod (62.9%); Moullsca larvae (26.1 %) and the most abundant of copepod genus were: paracalanus, Oncea, Oithona, Microsetella. Zooplankton in off shore stations were more than near shore stations. The most abundant of benthic groups were: Amphipoda (25%), Bivalve (18%), and polycheata (17%). The type of sediment in all stations was silt - clay. Max. and Min. anmount organic matter was 47.18% and 15.3% respectively.