Seasonal Diversity Analysis of Epiphytic Diatom Species Gyrosigma and Pleurosigma in Chabahar Bay
Keywords:
Epiphytic diatoms, Gyrosigma, Pleurosigma, Biodiversity, Environmental factors, Chabahar BayAbstract
Chabahar Bay, situated on the southeastern coast of Iran, is a unique marine ecosystem distinguished by its rich biodiversity and complex ecological interactions. This study investigates the seasonal dynamics of epiphytic diatoms, specifically the genera Gyrosigma and Pleurosigma, which are integral to primary productivity and nutrient cycling within the bay. Over a one-year period, diatom samples were collected from six strategically selected stations, each representing diverse habitats, including rocky substrates, seagrass beds, and algal mats. A total of 12 species from Gyrosigma and 6 species from Pleurosigma were identified, demonstrating their adaptability and resilience in response to varying environmental conditions. The research highlighted significant seasonal variations in diatom abundance and diversity, with notable species such as Gyrosigma eximium, Gyrosigma baculum, and Pleurosigma elongatum consistently present across all seasons. Statistical analyses, including the calculation of diversity indices (Simpson and Shannon), revealed fluctuating community structures influenced by factors such as water temperature, salinity, and nutrient concentrations (nitrite, nitrate, and phosphate). Principal Component Analysis (PCA) identified temperature, salinity, silicate, dissolved oxygen, and pH as critical parameters shaping diatom distribution and abundance. Moreover, the study underscores the role of epiphytic diatoms as sensitive bioindicators of environmental health, reflecting shifts in water quality and ecosystem changes due to anthropogenic pressures. Understanding the intricate relationships between diatoms and their environment is crucial for developing effective conservation strategies. This research contributes valuable insights into the ecological dynamics of Chabahar Bay and emphasizes the necessity of ongoing monitoring of diatom populations to inform sustainable management practices. By integrating findings from diatom studies with broader environmental assessments, we can enhance our strategies to protect and sustain this vital marine ecosystem against the backdrop of ongoing ecological challenges.
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