M. Arasimowicz

Assessment of the Black Sea Ecosystem Pollution With Copper and Cadmium In Selected Bays of Sevastopol Region

A high level of anthropopressure has been registered in Sevastopol region, connected with its strategic role as the main city in the region, but also due to Russian Black Sea Fleet stationing there for many years. A significant source of the Black Sea contamination in Sevastopol area is the industry located in this city, municipal waste and agriculture. Implementing measures aimed at protection of the Black Sea and the evolution of their results requires monitoring conducted in the regions with various levels of anthropopressure. The work was aimed at the assessment of copper and cadmium content in water and algae in selected bays of the Black Sea in the vicinity of Sevastopol. Samples of water and algae were collected in August 2012 from eight Sevastopol bays (Galubaja, Kozacha, Kamyshova, Kruhla, Strieletska, Pishchana, Pivdenna and Sevastopolska) and from the open sea in the vicinity of Fiolent. Algae (Cystoseira barbata and Ulva rigida) were collected from the same places. Collected water was preserved on the sampling place and brought to the laboratory where its copper and cadmium concentrations were assessed. Collected algae were rinsed in distilled water, dried, then homogenised and mineralised. Copper and cadmium content were determined in the mineralizates using ASA method with electrothermal atomisation. Cadmium concentration in water ranged from 0.13 to 1.74 μg Cd∙dm-3, and copper from 7.07 to 22.56 μg Cd∙dm-3. Considerable differences in the content of the analysed elements were registered in individual bays. The highest content was assessed in Galubaja and Sevastopolska bays, whereas the lowest one in the water collected in the open sea and in Pivdenna bay. Copper concentrations in the analysed algae fluctuated from 3.375 to 14.96 mg Cu∙kg-1 d.m. No differences were noted in this element content between the algae species. Cadmium content in the algae ranged from 0.133 to 1.133 mg Cd∙kg-1 d.m. Higher accumulation of cadmium was observed in Cystoseira barbata than in Ulva rigida. The value of copper bioaccumulation coefficient (BC) ranged from 181 to 1201, whereas cadmium from 181 to 5256. The contents of the analysed metals, both in biotic and abiotic elements of the studied ecosystems point to anthropogenic enrichment and the results obtained for Sevastopolska, Galubaja and Kozacha bays indicate a hazardous, excessive bioaccumulation of copper and cadmium and to potential threat to the life of aquatic organisms and seafood consumers.

CONTENT OF REDUCED GLUTATHIONE FORM AS A BIOMARKER OF OXIDATIVE STRESS IN SPINACH PLANTS GROWING IN SOIL CONTAMINATED WITH ZINC

The aim of the paper is the assessment of the efficiency of anti-oxidative system in spinach plants growing in the substratum polluted with zinc. The assessment was conducted on the basis of changes of reduced glutathione (GSH) form concentration in the plant aboveground organs. Spinach plants, ‘Matador’ c.v., were cultivated in soils contaminated with zinc in two pot experiments conducted in 2010 and 2011. The experimental substratum was light, slightly soil with granulometric composition of sandy silt loam. Zinc in the acetate form, was supplied to the soil in four doses corresponded to this metal critical concentrations in soil with 0, I, II and III degrees of pollution with this element according to IUNG classification. Simultaneously, the control with natural Zn content in soil was maintained. Zn concentrations in spinach ranged from 412.8 to 1722 mg ∙ kg -1 d.m. and increased with growing degree of substratum pollution with this element. Over the course of the vegetation period the content of Zn in plants was generally greater. GSH content in spinach grown in both years of experiments fluctuated from 31.70 to 238 µg ∙ g -1 f.m. The biggest content of this compound in spinach was stated in the initial phase of plants growth. The plants tolerated only the first two Zn doses supplied to the substratum. Spinach growing in the objects where zinc additions to the soil equalled II and III degree of substratum pollution died shortly after germination. The plants from these objects in the initial growth phase contained significantly less GSH than spinach from the objects with two first degrees (0 and I) of substratum pollution with zinc or from the control. The content of reduced glutathione form in spinach is a good biomarker of oxidative stress caused by zinc presence in plants. Synthesis of a bigger amount of GSH conditions spinach plant resistance to over the norm zinc content in soil. The efficiency of anti-oxidative system in spinach is bigger in the initial phase of this plant growth.