Saproxylic insects and fungi in deciduous forests along a rural–urban gradient

For fungal OTU (operational taxonomic units) data: We extracted DNA from 200 mg of each sawdust sample using the Quick-DNA Fecal/Soil Microbe Miniprep Kit (Zymo Research, Irvine, CA, USA) following the manufacturer’s instructions. DNA quantity and quality were measured using Nanodrop. We determined fungal OTUs using the F-ARISA method with the fungal-specific primer ITS1 (Gardes & Bruns, 1993) fluorescently labelled at the 5’-end (FAM) and the unlabeled ITS4 (White et al., 1990). The size of the fluorescent amplified fragments was quantified using Peak Scanner software (version 1.0, Applied Biosystems, Inc.). Peaks with a size ranging from 390 to 1000 bp were considered in the analyses (Ranjard et al., 2001) and according to Taggart et al. (2011), peak sizes obtained were rounded to the nearest base pair. To avoid possible background noise, only peaks with a signal above 1% of the sum of all peak areas were included in the analyses (Li et al., 2007). Peaks that differed in size by more than 2.0 bp were each considered as separate fungal OTU (Barto et al., 2011). Within the datasets: “Composition_Fungal_OTUs_Beech_Abundance_sites”, “Composition_Fungal_OTUs_Oak_Abundance_sites”, and “Composition_Total_Fungal_OTUs_Abundance_sites” the column headings ex. “OTU_459” or “OTU_461” represent the peak sizes of fungal OTUs. So, each column represents a different fungal operational taxonomic unit (OTU), a potential proxy for fungal species richness. For description of landscape, forest site, and branch characteristics, see the second excel sheet in the excel data file of "saproxylic_insect_species_taxonomic_composition". For more details see Materials and Methods section in the article with the same title.