The saline organic-rich sediments: A short overview.

• Main Author: H. L. BANCIU
• Format: Article
• Language: English
• Published: Cluj University Press 2018-03-01
• Series: Aerul şi Apa: Componente ale Mediului
• Subjects: microbial dark matter; mud therapy; saline; sapropels; Ursu Lake
• Online Access: http://aerapa.conference.ubbcluj.ro/2018/PDF/16_BANCIU_129_135.pdf

Organic-rich sediments (or ‘sapropels’) are complex organo-mineral matrices that form at the O2-depleted bottom of stagnant water basins. Besides geochemical transformations, slow rate microbially-driven processes underpin the early diagenesis of these sediments. The fossil sapropels found in various marine or lacustrine environments are known as proxies for past climate or hydrological fluctuations. Present-day organic-rich sediments have been described both in fresh (‘gyttja’) and brackish or saline waters mostly in the boreal zones. They are currently used for agricultural or therapeutic purposes. Few saline lakes with significant deposits of modern sapropels are known worldwide. On Romanian territory, saline lakes with substantial organic-rich sediments are found in the Transylvanian Basin (e.g. Ursu Lake, Sovata) and in the South-Eastern part (e.g. the inland, athalassohaline Amara, and the coastal, thalassohaline Techirghiol lakes). The exploration of microbial diversity inhabiting the saline sapropels will improve our current understanding on the processes leading to formation and mineralization of organic-rich sediments of economic value.