A preliminary assessment of the physical-chemical features of water and sediments from different deltaic aquatic systems. Case study: Fortuna lake, Matita lake and Musura bay Danube Delta, Romania

Abstract

The deltaic aquatic systems are of significant importance, being the interface between the particular geographical environments and a much elaborated complex of ecosystems and biodiversity, the characteristics that confers the uniqueness of the Danube Delta territory. Due to natural and human-related pressures to which Danube Delta it is subject, it becomes imperative to diagnose and evaluate the quality of the environmental status in relation to the condition of the water and sediment characteristics. This paper aims to assess the preliminary environmental quality status (water and sediment) in three different aquatic systems situated in the Danube Delta edifice. A research survey was focused on specific sampling field activities, subsequent laboratory analysis, data processing and basic findings. In this sense, 26 water samples, 20 surficial sediment samples and 3 short cores were collected during May 2016, aiming to estimate the water-physical-chemical features and the lithological characteristics of the recent sediments. In water, the environmental indicators agreed generally with environmental standards. In sediments, the percentage distribution of the physical parameters varied according to the specific local environmental conditions of the investigated perimeters. The main findings emphasize the role of the local current conditions of the investigated lakes, sampling sites, seasonal changes in the water budget through hydrological network etc., which influences the water and sediment conventional variables. In conclusion, this study report satisfactory water quality conditions of the investigated lakes. As regards the sediments, the specific environmental conditions are the main factors that control the influx of allochthonous or autochthonous material.