Abstract In-growth mesh bag technique is widely used for assessing production and turnover of the fungal mycelium in soil, but remains poorly standardized. This research aims at testing the use of quartz sand of different particle size, as a filling for in-growth mesh bags, in order to obtain a maximum amount of fungal mycelium. Mesh bags were incubated in a Norway spruce forest in Central Russia in June and September. Mycelial biomass was higher in sand of coarse (>0.5 mm) particle size and reached maximum (up to 798 μg of mycelium dry weight g−1 sand) in June. A relatively short incubation time (up to 30 days) was sufficient for estimating mycelium biomass and for collecting mycelium for isotopic analyses. The δ13C and δ15N values of fungal mycelium collected at the depths of 10 and 25 cm did not differ. Mycelium was depleted by 2.5‰ in 15N compared to mycorrhizal and by 3.0‰ in 13C compared to saprotrophic fruit bodies. This observation should be taken into account in the isotope-based reconstructions of belowground food webs.

中文翻译：

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使用生长网袋收集真菌菌丝体：沙粒大小和季节性的影响

摘要 生长网袋技术被广泛用于评估土壤中真菌菌丝体的产生和周转，但仍缺乏标准化。本研究旨在测试使用不同粒径的石英砂作为生长网袋的填充物，以获得最大量的真菌菌丝体。网袋于 6 月和 9 月在俄罗斯中部的挪威云杉林中孵化。粗（>0.5 毫米）粒度的沙子中的菌丝体生物量较高，并在 6 月达到最大值（菌丝体干重 g-1 沙子高达 798 微克）。相对较短的孵育时间（最多 30 天）足以估计菌丝体生物量和收集菌丝体进行同位素分析。在 10 和 25 厘米深度收集的真菌菌丝体的 δ13C 和 δ15N 值没有差异。菌丝体被耗尽2。与菌根相比，15N 中为 5‰，与腐生子实体相比，13C 中为 3.0‰。在基于同位素的地下食物网重建中应考虑到这一观察结果。