Journal Article

How does the interaction between the stress status of bivalves (Mytilus galloprovincialis) and marine environmental factors unfold through a principal component analysis approach?

Nadir, Maryam, El Mourabit, Youssef, Lefrere, Latifa, Ait Haddou, Mohamed, Abou Oualid, Jaouad, Agnaou, Mustapha, Moukrim, Abdellatif, Ait Alla, Aicha, Mabrouki, Jamal, Abbassi, Mohamad

2025

Overview

The Bay of Agadir, located in Morocco, is of significant economic and ecological value, yet it has faced persistent pollution challenges due to industrial, port, and tourism activities. Despite recent improvements following the implementation of wastewater treatment plants, particularly in the Anza-Imouran sector, knowledge gaps remain regarding the interactions between marine environmental factors and pollution biomarkers in marine organisms. This study examines the influence of environmental factors on the biomarker responses of Mytilus galloprovincialis across three sites (Anza, Aourir, and Imouran) in Agadir Bay, covering the period from January 2017 to December 2018. Principal Component Analysis (PCA) was employed to explore the relationships between four key biomarkers (Catalase (CAT), Glutathione S-transferase (GST), Malondialdehyde (MDA), and Acetylcholinesterase (AChE)), and seven marine environmental factors (water temperature, air temperature, salinity, pH, dissolved oxygen, electrical conductivity, and precipitation). At Anza, Aourir, and Imouran, the first two principal components explained a significant portion of the total variance (80.19%, 78.63%, and 88.60%, respectively). Notable findings include a negative correlation between GST and water temperature ( r  = − 0.57) at Anza. In Aourir, CAT exhibited a positive correlation with rainfall and dissolved oxygen ( r  = 0.78 and r  = 0.41, respectively) but a negative correlation with pH and salinity ( r  = − 0.58 and r  = − 0.44, respectively). Additionally, GST was positively correlated with rainfall ( r  = 0.52), while showing a negative relationship with pH and water temperature ( r  = − 0.40 and r  = − 0.53, respectively). MDA was negatively correlated with salinity ( r  = − 0.59), and AChE was inversely associated with electrical conductivity ( r  = − 0.41). In Imouran, CAT was positively correlated with rainfall ( r  = 0.70), while exhibiting negative correlations with pH, salinity, and electrical conductivity ( r  = − 0.73, r  = − 0.60, and r  = − 0.61, respectively). GST showed a positive correlation with electrical conductivity and salinity ( r  = 0.55 and r  = 0.48), but a negative correlation with water temperature ( r  = − 0.47). MDA was positively correlated with rainfall ( r  = 0.66) and negatively with pH, electrical conductivity, and salinity ( r  = − 0.74, r  = − 0.58, and r  = − 0.67, respectively). These findings highlight the intricate relationship between marine environmental factors and biomarker variability in M. galloprovincialis , emphasizing the importance of further understanding their impact on marine organism health amid ongoing environmental changes. Graphical abstract

• Publisher: Springer International Publishing,Springer Nature B.V
• Subject: Acetylcholinesterase / Air temperature / Aquatic Pollution / Atmospheric Protection/Air Quality Control/Air Pollution / Biomarkers / Catalase / Climate change / Correlation / Dissolved oxygen / Earth and Environmental Science / Earth Sciences / Ecosystems / Effluents / Electrical conductivity / Electrical resistivity / Environmental changes / Environmental Chemistry / Environmental factors / Environmental Management / Environmental Science and Engineering / Enzymes / Glutathione / Glutathione transferase / Marine environment / Marine organisms / Mollusks / Mytilus galloprovincialis / Original Paper / pH effects / Plastic pollution / Pollutants / Principal components analysis / Rainfall / Salinity / Salinity effects / Seawater / Shellfish / Tourism / Tourist activities / Waste Management/Waste Technology / Waste Water Technology / Wastewater treatment / Wastewater treatment plants / Water Management / Water Pollution Control / Water temperature / Water treatment