Figures & data
Figure 1. Study site description: a) Satellite image illustrating the retreat of the Exploradores glacier in last 70 years. Color lines show the age-limit of the three stages of soil development. b) Photo showing a frontal view of Exploradores forefield glacier. c) A principal component analysis (PCA) of soil features during soil development. F and P-value correspond to PerManova test results. Open symbols: stage 1; light grey: stage 2; dark grey: stage 3
![Figure 1. Study site description: a) Satellite image illustrating the retreat of the Exploradores glacier in last 70 years. Color lines show the age-limit of the three stages of soil development. b) Photo showing a frontal view of Exploradores forefield glacier. c) A principal component analysis (PCA) of soil features during soil development. F and P-value correspond to PerManova test results. Open symbols: stage 1; light grey: stage 2; dark grey: stage 3](/cms/asset/f80bb262-e31c-40a5-b5f8-14a24501347e/uaar_a_1820124_f0001_oc.jpg)
Table 1. Changes in soil biogeochemical features across three stages of soil development of the NPFI chronosequence
Table 2. Differences in the relative abundance of microbial groups, measured as ratios across the three stages of soil development of the NPFI glaciar retreat chronosequence
Figure 2. Changes in microbial community abundance and the nifH gene (i.e. nitrogen cycle gene) across stages of soil development at the NPIF. In a) Archaeal, b) Bacterial, c) Fungal abundances, and in d) nifH gene-copy number. Bars represent mean values and ±1 SE of gene abundance from five samples. Different letters shows significant differences across stages of soil development for F and P-values of ANOVA given in right upper corner
![Figure 2. Changes in microbial community abundance and the nifH gene (i.e. nitrogen cycle gene) across stages of soil development at the NPIF. In a) Archaeal, b) Bacterial, c) Fungal abundances, and in d) nifH gene-copy number. Bars represent mean values and ±1 SE of gene abundance from five samples. Different letters shows significant differences across stages of soil development for F and P-values of ANOVA given in right upper corner](/cms/asset/6f03fbf4-8fa6-401b-af8c-168453634695/uaar_a_1820124_f0002_b.gif)
Figure 3. Changes in the relative abundance of microbial groups as a function of changes in (a) soil C:N and (b) soil pH (i.e., soil variables with the highest relative contribution to change in microbial abundance). Circles: fungal-to-bacterial ratios; Triangles: archaeal-to-bacterial ratios across three stages of the NPFI. (c), (d) Changes in nifH gene copy number. For all panels, open symbols: stage 1; light grey: stage 2; dark grey: stage 3. Solid lines represent significant linear regression adjusted for variables
![Figure 3. Changes in the relative abundance of microbial groups as a function of changes in (a) soil C:N and (b) soil pH (i.e., soil variables with the highest relative contribution to change in microbial abundance). Circles: fungal-to-bacterial ratios; Triangles: archaeal-to-bacterial ratios across three stages of the NPFI. (c), (d) Changes in nifH gene copy number. For all panels, open symbols: stage 1; light grey: stage 2; dark grey: stage 3. Solid lines represent significant linear regression adjusted for variables](/cms/asset/fff8c550-b603-4f80-9323-c38f18701736/uaar_a_1820124_f0003_b.gif)
Figure 4. Differences in mass loss (buried) across stages of soil development in the NPIF chronosequence. (a) Mass loss of Whatman filter after nineteen months in three stages of soil development. T1: after seven months, T2: after 12 months; T3: after nineteen months. (b) Relationship between mass loss of Whatman filters as a function of higher fungal abundance across stages of the NPIF chronosequence. Open circle: stage 1; light grey: stage 2; dark grey: stage 3. Solid lines represent a significant linear relationship (all data included)
![Figure 4. Differences in mass loss (buried) across stages of soil development in the NPIF chronosequence. (a) Mass loss of Whatman filter after nineteen months in three stages of soil development. T1: after seven months, T2: after 12 months; T3: after nineteen months. (b) Relationship between mass loss of Whatman filters as a function of higher fungal abundance across stages of the NPIF chronosequence. Open circle: stage 1; light grey: stage 2; dark grey: stage 3. Solid lines represent a significant linear relationship (all data included)](/cms/asset/ef0a678c-aa66-4cc7-b7c4-a5b5705f0f77/uaar_a_1820124_f0004_b.gif)