Link; https://daac.ornl.gov/cgi-bin/dsviewer.pl?ds_id=1264

This data set provides the concentrations of soil microbial biomass carbon (C), nitrogen (N) and phosphorus (P), soil organic carbon, total nitrogen, and total phosphorus at biome and global scales. The data were compiled from a comprehensive survey of publications from the late 1970s to 2012 and include 3,422 data points from 315 papers. These data are from soil samples collected primarily at 0-15 cm depth with some from 0-30 cm. In addition, data were compiled for soil microbial biomass concentrations from soil profile samples to depths of 100 cm. The biome map and six estimates of C and N storage and C:N ration in soil microbial biomass are provided in a single netCDF format file.