Sporocarps of wood decay fungi contain functional information about how different taxa partition carbon and nitrogen resources from wood. We combined carbon and nitrogen concentrations, isotopic ratios (¹³C:¹²C, ¹⁵N:¹⁴N, and ¹⁴C:¹²C, expressed as δ¹³C, δ¹⁵N, and Δ¹⁴C values), and compositional patterns in wood, cellulose, and sporocarps to investigate functional and isotopic differences in six taxa of decay fungi during log decomposition. Radiocarbon (Δ¹⁴C) measurements separated fungi into heartwood colonizers (Fomitopsis and Hericium, ~30+-year-old carbon) and sapwood colonizers (Mycena, Hypholoma, and Trametes, 1-12-year-old carbon). Decay modes influenced δ¹³C, with Hericium, a selective white-rot fungus, higher in δ¹³C than nonselective white-rot fungi because Hericium preferentially assimilated ¹³C-enriched hemicellulose rather than cellulose. Fungal δ¹⁵N was lower in heartwood colonizers than in sapwood colonizers, presumably reflecting greater N turnover and ¹⁵N enrichment in sapwood than in heartwood. Sporocarp δ¹⁵N correlated with sporocarp %N and with the relative proportion of protein in N-containing pyrolysis products because fungal protein was 4–5‰ higher in δ¹⁵N (and 3–4‰ higher in δ¹³C) than non-protein. From these measurements, we improved the quantitative and conceptual understanding of how sources, composition and metabolic processing determined isotopic composition of fungi.

木材腐烂真菌的果皮含有关于不同分类单元如何分配木材中碳和氮资源的功能信息。我们结合碳和氮的浓度，同位素比（¹³ C：¹² C，¹⁵ N：¹⁴ N，和¹⁴ C：¹² C，表示为δ ¹³ C，δ ¹⁵ N，和Δ ^14个C值），并且组成的图案在木材，纤维素和果皮，以研究对数分解过程中六个腐烂真菌类群的功能和同位素差异。放射性碳（Δ ¹⁴ C）测量分离真菌进入心材殖民者（Fomitopsis和猴头，〜30岁以上的碳）和边材定居者（Mycena，Hypholoma和Trametes的1-12岁的碳）。衰减模式影响δ ¹³ C，与猴头，选择性白腐菌，在δ更高¹³下比非选择性白腐菌因为猴头优先同化¹³ C-富集的半纤维素而不是纤维素。真菌δ ¹⁵ n为心材殖民者比边材殖民者下，大概反映更大Ñ周转和¹⁵ Ñ富集边材比心材。子实体δ ¹⁵n，其中子实体％N，并用蛋白在含N的热解产物的相对比例相关联，因为真菌蛋白是4-5‰高于δ ¹⁵ N（和3-4‰，δ更高¹³ C）比非蛋白。通过这些测量，我们提高了对来源，组成和代谢过程如何确定真菌同位素组成的定量和概念性理解。