Uptake of 87Sr from microcline and biotite by ectomycorrhizal fungi in a Norway spruce forest

• Published in: Soil biology & biochemistry Vol. 38; no. 8; pp. 2487 - 2490
• Main Authors: Wallander, Håkan, Hagerberg, David, Åberg, Göran
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-08-2006; New York, NY Elsevier Science
• Subjects: 87Sr/ 86Sr ratio; Agronomy. Soil science and plant productions; Biochemistry and biology; Biological and medical sciences; Biotite; Chemical, physicochemical, biochemical and biological properties; Economic plant physiology; Ectomycorrhiza; ectomycorrhizae; field experimentation; forest soils; Fundamental and applied biological sciences. Psychology; Microcline; mycorrhizal fungi; nutrient uptake; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Picea abies; radiolabeling; silicate minerals; Soil science; strontium; Strontium isotopes; symbiosis; Symbiosis (nodules, symbiotic nitrogen fixation, mycorrhiza...); Weathering; Sweden; Weathering; Microcline; Ectomycorrhiza; Biotite; Strontium isotopes; 87Sr/ 86Sr ratio; Forests; 87Sr/86Sr ratio; Symbiont; Strontium; Absorption; Softwood forest tree; Gymnospermae; Mycorrhiza; Coniferales; Spermatophyta; Soil science; Isotopes; Picea abies
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/j.soilbio.2006.02.002

Ectomycorrhizal (EM) fungi growing in symbiosis with tree seedlings have been found in laboratory experiments to stimulate weathering and the uptake of nutrients from silicate minerals. In the present study, we used the natural abundance of strontium isotopes to confirm that these fungi obtain strontium from biotite and microcline under field conditions. Minerals enriched in radiogenic
87Sr were introduced into fungal in-growth mesh bags and placed under a 5–10
cm thick humus layer developed on boulders in a Norway spruce (
Picea abies (L.) Karst) forest in south-western Sweden. EM root tips were sampled above the mesh bags and the
87Sr/
86Sr ratio was used to calculate the fraction of Sr in the root tips that originated from the minerals. In the EM root tips sampled above the mesh bags containing the different minerals, 1.5% of the Sr originated from biotite and 6.4% from microcline. The amount of Sr was more than 300 times higher in the mesh bags containing microcline than in those containing biotite, indicating that proportionally more Sr was released from the biotite. This study demonstrates that EM fungi have the potential to take up measurable amounts of nutrients, such as Ca and K, from microcline and biotite in the field.