Stable nitrogen isotope ratio in wood substrates and xylotrophic fungi in forest ecosystems of Western Siberia

• Published in: Russian journal of ecology Vol. 45; no. 6; pp. 539 - 546
• Main Authors: Mukhin, V. A, Voronin, P. Yu, Velivetskaya, T. A, Ignat’ev, A. V
• Format: Journal Article
• Language: English
• Published: Moscow Springer-Verlag 01.11.2014; Pleiades Publishing; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; climatic factors; decayed wood; Ecology; Environment; forest ecosystems; Forests; Fungi; Isotopes; Life Sciences; mineralization; Nitrogen; Russian Academy of Sciences; Terrestrial ecosystems; This Number of the Journal is Dedicated to the 70th Anniversary of Institute of Plant and Animal Ecology; Ural Branch; Wood; Siberia; Russia, Siberia; stable isotopes; xylotrophic fungi; Western Siberia; nitrogen; wood pool; forest ecosystems
• ISSN: 1067-4136; 1608-3334
• DOI: 10.1134/S1067413614060095

It has been shown that wood substrates are the main source of nitrogen for xylotrophic fungi, which have almost the same isotopic signature as their substrate. This fact and a strong positive correlation in nitrogen isotope composition between the substrates and fungi provide evidence for a closed type of nitrogen turnover in the wood-fungus system that is based on retention and repeated utilization of this element. Its isotope composition in the fungi depends on that in the substrate, which is enriched in the heavy isotope in deciduous wood and in the light isotope in coniferous wood. The nitrogen isotope composition in the fungi and wood substrates does not depend on the degree of wood mineralization or climatic conditions, and δ¹⁵N is not an indicator of fungal physiological activity or wood decomposition rate but rather a marker of the isotopic composition of nitrogen sources for the fungi.