Biodiversity in the Black Sea: effects of climate and anthropogenic factors

Abstract

The Black Sea ecosystem and diversity underwent dramatic adverse changes during the 1960s and, especially, 1970s and 1980s of the last century. Anthropogenically-induced eutrophication increased through greater biogenic flow, dumping and pollutant discharge, in turn causing red tides, fish kills and oxygen depletion over the northwestern shelf. Anthropogenic pressures, associated with the economic situation of the Black Sea countries, has decreased during the last decade, allowing some improvement in the state and biodiversity of the ecosystem. The abundances of several native species have increased. However, mediterranization-the invasion by species from the adjacent basin and beyond-has continued. The conclusion is grounded, that biodiversity is not only inter-and intra-species diversity but also spatial-temporal variability, abundance and productivity dynamics, differences of the metabolic strategies providing sustainable existence in the changing environment. Biodiversity at the intraspecies level expresses itself in spatial and temporal variations of the Black Sea biota. It has been shown, that preservation of the Black Sea ecosystem's biodiversity must be based on the measures which should be undertaken in national and social spheres, and be directed to the recreation, stabilization and conservation of this unique sea basin. Measures must be implemented nationally to conserve, stabilize or recreate the ecosystem biodiversity of this unique sea basin.

Climate Change and Biodiversity Effects in Turkish Seas

“…The Sea of Marmara exhibits peculiar hydrological conditions, with low salinity waters coming from the Black Sea stratifying over saline waters of Mediterranean origin on the bottom (Unluata et al, 1990). In recent years, climatic change favoured an increase of biotic penetration from the Sea of Marmara into the Black Sea, which therefore has been undergoing a process of 'Mediterranization' (Tokarev & Shulman, 2007;Turan et al 2010;Yaglioglu et al 2014).…”

Mixing and Transport

“…It has been shown by Tokarev and Shulman, (2007 with regards to the existing information in the study area.…”

Heavy Metals Influence on the Ctenophores Mnemiopsis Leidyi and Beroe Ovata Bioluminescence

“…Most contaminants entering the marine environment become local and regional pollution sources disrupting the normal biological processes (Тokarev 2006). Toxic elements actively affect reproduction and metabolic activities of plankton organisms representing the bottom levels of a food chain (Marine report 2009;Luk'yanenko & Cherkashin 1987;Finenko et al 2003;Tokarev & Shulman 2007). Accumulation of heavy metals in organisms of different taxonomic groups, as well as behavioral responses of hydrobionts to the presence of heavy metal ions, have been quite well investigated (Vasil'kov 2005;Klishko et al 2007;Mosharov et al 2009).…”