A Comprehensive Review on Microplastic Pollution in Aquatic Ecosystems and Their Effects on Aquatic Biota

Plastic wastes released into the environment break down into fine particles due to exposure to meteorological events such as wind, precipitation, UV radiation, and abrasion. These smaller plastic particles, ranging between 1 µm and 5 mm, are called microplastics and they can be transported over longer distances with the aid of erosion, waste water discharges, winds, and currents. Aquatic habitats are the final sink for many pollutants including heavy metals, pesticides, nanoparticles, and microplastics released into environment. Thus, these pollutants are considered a major threat to aquatic life. In this study, we reviewed studies i: focusing on the type, size and the quantity of microplastics observed in freshwater and marine ecosystems, and ii: studies on the effects of microplastics on aquatic organisms. The data gathered clearly indicates that microplastics are quite abundant in freshwater and marine ecosystems. Furthermore, nearly in all studies reviewed, microplastic uptake and alterations in several biochemical parameters depending on microplastic exposure are recorded. The studies also point out that microplastics will become a global serious health concern both for human beings and aquatic organisms in the near future

A technical guide to develop a statistically valid fish-based index in compliance with the water framework directive: an evaluation for Turkish freshwaters

Abstract Fish are considered as reliable indicators of environmental quality and during the last decades several fish-based indices have been developed to assess the ecological status of water bodies in compliance with the water framework directive. The high number of fish species with a high degree of endemism, lack of knowledge on ecological requirements of certain fish species, absence of a complete dataset for reference conditions, and great variation among freshwater types complicate the development of fish-based indices for Turkish freshwaters. However, this is still possible using statistical approaches. This paper presents a practical guide which is mainly based on the recent approaches that have frequently been used in other countries worldwide. Data collection, metric selection and scoring, ecological quality ratio (EQR) calculation and validation steps are described and discussed with respect to the limitations and available data for Turkish freshwaters. The guide documented here, with minor adjustments, has a potential to be adopted as a fish-based assessment approach for the ecological status in freshwaters in Turkey and adjacent countries

THE EVALUATION OF THE GROWTH PERFORMANCE OF A CYANOBACTERIAL ISOLATE PHORMIDIUM LUCIDUM (KÜTZİNG EX GOMONT 1892) GROWN UNDER DIFFERENT ENVIRONMENTAL CONDITIONS AND ITS USE AS A DIETARY SOURCE FOR DAPHNIA MAGNA (STRAUS 1820)

This study presents the effect of cyanobacterium isolated from BollukLake (Konya, Türkiye) which is a saline lake on the growth performance of Daphniamagna. Isolated cyanobacteria species were identified as Phormidium lucidumaccording to its 16S rDNA sequences. The effects of different growth conditionsincluding pH (7.18, 8.15, 9.17 and 10.26), light intensity (1200, 2400, 3600 and 4800lux), temperature (10, 20, 25 and 30°C) and nitrogen concentrations (0.25, 0.5, 1.0 and1.5 g/L) on P. lucidum was studied. Effects of each environmental factor onbiochemical composition (total protein, total lipid and chlorophyll-a concentration) ofP. lucidum were also studied. The optimum growth conditions were found as pH 7.18,ambient temperature 20°C, nitrogen 0.25 g/L and light intensity 3600 lux, after a 2-week incubation period. The effects of various mixtures of the cyanobacteria andChlorella vulgaris which is a common feed for Daphniids were also evaluated for theireffects on the growth rates of D. magna. The best growth rate for D. magna wasobtained in the medium containing 100% P. lucidum at the end of the 13ᵗ ͪ day