Title Depleted 15N in hydrolysable-N of Arctic soils and its implication for mycorrhizal fungi-plant interaction
Author Yano, Y.; Shaver, G.R.; Giblin, A.E.; Rastetter, E.B.
Author Affil Yano, Y., Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA. Other: Municipality of Anchorage, Human and Health Services
Source Biogeochemistry (Dordrecht), 97(2-3), p.183-194, . Publisher: Springer, Dordrecht - Boston - Lancaster, International. ISSN: 0168- 2563
Publication Date Mar. 2010
Notes In English. 53 refs. GeoRef Acc. No: 310479
Index Terms fungi; geochemistry; isotopes; soils; soil chemistry; tundra; variations; United States--Alaska; Arctic region; Alaska; amino acids; arctic environment; isotope ratios; N- 15; N-15/N-14; nitrogen; organic acids; organic compounds; Plantae; stable isotopes; Toolik Lake; United States
Abstract Uptake of nitrogen (N) via root- mycorrhizal associations accounts for a significant portion of total N supply to many vascular plants. Using stable isotope ratios (delta 15N) and the mass balance among N pools of plants, fungal tissues, and soils, a number of efforts have been made in recent years to quantify the flux of N from mycorrhizal fungi to host plants. Current estimates of this flux for arctic tundra ecosystems rely on the untested assumption that the delta 15N of labile organic N taken up by the fungi is approximately the same as the delta 15N of bulk soil. We report here hydrolysable amino acids are more depleted in 15N relative to hydrolysable ammonium and amino sugars in arctic tundra soils near Toolik Lake, Alaska, USA. We demonstrate, using a case study, that recognizing the depletion in 15N for hydrolysable amino acids (delta 15N=-5.6 ppm on average) would alter recent estimates of N flux between mycorrhizal fungi and host plants in an arctic tundra ecosystem. Copyright 2009 Springer Science+Business Media B.V.
URL http://hdl.handle.net/10.1007/s10533-009-9365-1
Publication Type journal article
Record ID 65007120