VetusLignum wrote:What does a 1% ratio mean? A biomass of 1 fungus per 100 bacteria?
The FFA ratios of PLFA, RNA and proteins were calculated using the amounts of lipids, the proportion of sequences and the abundance of proteins, respectively. The proportion of fungi in relation to bacteria was expressed as follows:
% proportion F: B = Fu n gun l in de xB acterial in de x × 100
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4977315/
and in this same study from 2016 where they analyze a grassland soil
In order to study the link between microbial community structures and the soil carbon cycle, we chose two soils from the Jena biodiversity experiment, a large-scale grassland diversity experiment established in 2002 in Jena, Germany (Roscher et al., 2004). Soils were selected based on the composition of the microbial community derived from PLFA 2007 (Lange et al., 2014).), So that the soils had similar physical and chemical properties, but differed in the structure of their microbial community, and in particular in their F: B ratio. Therefore, the two soils were named "low soil F: B" and "high soil F: B". This nomenclature has been followed throughout this report. The two soils had a similar soil texture (44,6% sand, 39,6% silt, 15,8% clay) and pH 7,75. The C, N, and C: N ratios of soils were also very similar at 2, 0,2, and 10,2%, respectively (Supplementary Figure S1). The two soils differed in the number of plant species (four in the low F: B soil, eight in the high F: B soil) but not in the number of functional groups in the plant ( one grass, one small grass, one tall and legume in both soils). Soil was collected from stainless steel cores in April 2014 to a depth of 0-10cm (from three spatially replicated plots for each soil class), sieved (<2mm), all visible roots were were removed, homogenized and stored 12 days before the establishment of the mesocosms.
I pass the detail of the measurement protocol
Before setting up the experiment on the mesocosm, the composition of the microbial community using PLFA biomarkers was reassessed with soils from the same diversity plots. The total bacterial PLFA content was 18,46 ± 0,05 and 23,55 ± 0,23 μg / g; while the fungal PLFA content was measured at 0,52 ± 0,002 and 0,99 ± 0,01 μg / g in soils with low F: B content and high F: B content, respectively.The proportion of fungi per cent compared to bacteria has been estimated at 2,8 ± 0,01 and 4,2 ± 0,07 at low F: B and high F: sol B, respectively (Figure Figure 1A 1A). The F: B ratio, derived from PLFA, of the high F: B soil microbial community was 1,5 times that of the low F: B soil (single-factor ANOVA; p <0,001 ).
So we stay within 1 to 5%
VetusLignum wrote:What I have quoted is the consensus of many soil microbiologists.
Which