Impact of micro- and macroelement content on potential use of freshwater sediments (gyttja) derived from lakes of eastern Latvia

Abstract

Organic-rich freshwater sediments formed from the remains of water plants, plankton and benthic organisms, which are transformed by microorganisms, and mixed with mineral components supplied from the lake basin, are known as gyttja (sapropel or dy). Gyttja is a valuable natural resource that can be used in various fields such as agriculture, forestry, construction, chemical industry, balneology and the latter ones are especially interested in chemical composition and safety of natural materials. The aim of the study was to investigate micro- and macro-element content of gyttja derived from lakes of eastern Latvia (north-east of Europe). Depending on composition, sediment samples were identified as peaty, various algae, green algae, diatom, carbonate and organic-silicate types of gyttja. Dried samples were wet-digested by heating in HNO/HO solution until complete mineralization. Sample solutions were analysed by atomic absorption spectrometry (AAS) to detect concentration of Ca, Fe, K, Mg, Mn, Na and Zn, but inductively coupled plasma mass spectrometry (ICP-MS) was applied for As, Ba, Cd, Co, Cr, Cu, Li, Ni, Pb, Rb, Se, Sr and V concentration measurements. Total content of elements was variable; higher macroelement concentration was detected for gyttja of carbonate type, but higher microelement concentration-for organic-silicate gyttja. As concentration of several elements was much lower than permitted by the European Union legislation, gyttja is not only safe, but also highly valuable resource applicable in organic agriculture. There is a potential to use gyttja as a peloid in health care, but element bioavailability should be estimated likewise.

Peat as a Raw Material for Plant Nutrients and Humic Substances

“…Small amounts of other trace elements compared to iron concentration were detected in both acid extracts. Data in the literature confirm experimentally obtained results that peat contains high concentrations of Fe, and the concentrations of other trace elements vary across a wide range [19,30,31].…”

Natural medicinal resources and their therapeutic applications

“…Gyttja is a Swedish term for organic-rich freshwater mud, which is a mixed organic-rich mud that is rapidly accumulated in eutrophic lakes; the organic component that makes up to 40% of the dry mass results from the partially anaerobic putrefaction of plankton. It is a unique geological formation occurring at the bottom of water bodies (mostly in overgrowing, eutrophic lakes) [28]. According to Korde [15], gyttja contains not less than 15% and up to 90% of organic matter.…”

“…However, gyttja is also known for its high mineral content. For example, in gyttja samples derived from lakes of eastern Latvia, minerals such as Ca, Fe, Mg, K, Mn, Na, Zn, and Ba were detected at concentrations above 50 mg/kg [28]. Sr, Cu, Cr, Ni, Pb, V, As, Co, Rb, Li, Se, and Cd were found at concentrations below 50 mg/kg.…”

“…Sr, Cu, Cr, Ni, Pb, V, As, Co, Rb, Li, Se, and Cd were found at concentrations below 50 mg/kg. Because metal elements are incorporated in organic substances, it is important to evaluate the concentration of potentially toxic microelements such as As, Cd, Cr, and Pb [28].…”

Effectiveness of Sapropel Application in Diets of Geese

“…Sapropels and their products are environmentally friendly, non-toxic, and contain essential nutrients (Stankevica et al, 2016). Sapropels (gyttja or dy) are centuries-old freshwater sediments, which contain up to 15% of organic substances (Kurzo et al, 2004;Obuka et al, 2015) and are formed of benthos, i.e., remnant phytoplankton and zooplankton, and fractions of soil humus (Kurzo, 2005;Rutina et al, 2013;Vincevica-Gaile and Stankevica, 2018). Sapropels can only develop in stagnant fresh waters, at bottoms of stagnant lakes with reduced oxygen availability (Lacis, 2003;Obuka et al, 2015).…”