Spatiotemporal study of algal veget ation in intertidal area of Bandar-e-Lengeh in south of Iran, (Persian Gulf)

The study of floristic and ecological aspects of seaweeds can provide the basic know ledge for cultivation and commercial exploitatio n of these marine resources. In this investigation, floristic and ecological aspect of the algal vegetation of inter tidal regions of the Bandar-e-Len geh were studied since Oct. 2001 for one year. Three sites were selected in coastal lines of the B andar-e-Lengeh and monthly sampling was carried out along the permanent horizontal transects established in each selected site, which their length differed depend on sites slop gradie nt. Along these transects thirty quadrate were randomly sampled in each month. Environmenta l factors such as air and seawater temperature, salinity, pH, EC and light intensity were measured. In 4 subunit (25 cm2) of each quadrate alga l vegetation were collected and cleaned in laboratory then both fresh and dry weight of each indi vidual species in each subunit were determined an d all data were analyzed using SPSS software. As the results totally 129 species of marine algae including 55 Red, 29 brown, 30 green, 8 blue-green and 7 diatoms and two sea grasses were rec ognized . Number of species was increased from Feb. to May and was seriously decreased in October. Mean primary production of brown, Red, green, blue-green and sea grasses were 51 .5, 48.3, 41.1, 11.8 and 0.62 (gr. Dw/ m2) resp ectively and mean total dried biomass was 152 g r Dw/m2. Average total primary production o f the seaweeds for site1, 2 and 3 were 178, 154 and 119gr.Dw/m2 respectively which were significantly (P 0.05) differences. Average seasonal production also were significantly difference (P 0.05) for spring (112), summer (197), f all (158) and winter (150). Type of substratum, depth of water, and season were important factors which affected significantly the contribution of seaweeds.

The study of floristic and ecological aspects of seaweeds can provide the basic know ledge for cultivation and commercial exploitatio n of these marine resources. In this investigation, floristic and ecological aspect of the algal vegetation of inter tidal regions of the Bandar-e-Len geh were studied since Oct. 2001 for one year. Three sites were selected in coastal lines of the B andar-e-Lengeh and monthly sampling was carried out along the permanent horizontal transects established in each selected site, which their length differed depend on sites slop gradie nt. Along these transects thirty quadrate were randomly sampled in each month. Environmenta l factors such as air and seawater temperature, salinity, pH, EC and light intensity were measured. In 4 subunit (25 cm2) of each quadrate alga l vegetation were collected and cleaned in laboratory then both fresh and dry weight of each indi vidual species in each subunit were determined an d all data were analyzed using SPSS software. As the results totally 129 species of marine algae including 55 Red, 29 brown, 30 green, 8 blue-green and 7 diatoms and two sea grasses were rec ognized . Number of species was increased from Feb. to May and was seriously decreased in October. Mean primary production of brown, Red, green, blue-green and sea grasses were 51 .5, 48.3, 41.1, 11.8 and 0.62 (gr. Dw/ m2) resp ectively and mean total dried biomass was 152 g r Dw/m2. Average total primary production o f the seaweeds for site1, 2 and 3 were 178, 154 and 119gr.Dw/m2 respectively which were significantly (P 0.05) differences. Average seasonal production also were significantly difference (P 0.05) for spring (112), summer (197), f all (158) and winter (150). Type of substratum, depth of water, and season were important factors which affected significantly the contribution of seaweeds.