Evaluation of spatial and temporal variations in marine sediments quality using multivariate statistical techniques

Area of Science:

• Environmental Science
• Geochemistry
• Marine Biology

Background:

• Sediment quality is crucial for aquatic ecosystem health.
• Matanzas Bay, Cuba, faces potential environmental pressures.
• Understanding contaminant distribution is vital for management.

Purpose of the Study:

• To assess spatial and temporal variations in Matanzas Bay sediment quality.
• To identify key variables influencing sediment environmental quality.
• To introduce new data on Vanadium and Arsenic concentrations in bay sediments.

Main Methods:

• Annual collection of surface sediment samples from 2005-2008 at eight stations.
• Analysis of 12 variables: heavy metals (Zn, Cu, Pb, As, Ni, Co, Mn, V), Al, Fe, CO₃²⁻, and total hydrocarbons (THC).
• Application of multivariate statistical techniques: Principal Component Analysis (PCA), Cluster Analysis (CA), and Linear Discriminant Analysis (LDA).

Main Results:

• Heavy metals (Zn, Cu, Pb, V, As) and total hydrocarbons (THC) were identified as the most significant contributors to sediment quality variations.
• Concentrations of Vanadium (V) and Arsenic (As) were determined for the first time in this ecosystem.
• Sediment samples were differentiated into three distinct groups along the bay, indicating spatial variations.
• Temporal variations in sediment environmental quality were observed over the sampling period.

Conclusions:

• Multivariate statistical methods effectively interpreted environmental data, even with a limited dataset.
• Sediment quality in Matanzas Bay is influenced by specific heavy metals and hydrocarbons.
• The study provides a baseline for future monitoring and management of Matanzas Bay's sediment quality.