https://doi.org/10.5061/dryad.sbcc2frhh

Description of the data and file structure

All data was collected from published paper by searching “soil particulate organic carbon” at Web of Science and Google Scholar.  We derived the data points from tables involving soil POC and/or extracted from figures vis the Engauge Digitizer software version 10.7. Climate, edaphic, and microbial data not mentioned in papers were extracted from global datasets following our previous studies. SOC, TC, and BD were downloaded from the Harmonized World Soil Database (HWSD, https://daac.ornl.gov/cgibin/dsviewer.pl?ds_id=1247) at a 0.05° × 0.05° resolution grid. Soil C, BD, and TN were extracted from the IGBP-DIS dataset (IGBP, https://daac.ornl.gov/SOILS/guides/igbp-surfaces.html) at a spatial resolution of 0.5′ × 0.5′. MAT and MAP were obtained from the WorldClim database version 2 with a spatial resolution of 30 seconds during 1970 – 2000 (https://www.worldclim.org/data/worldclim21.html). Missing data are entered as Na.

Files and variables

File: POC_0_100cm.csv

Description: 

Variables

• ID: Original Sample ID
• NO.: Sample ID
• Country:
• bd_igbp (g cm-3): Bulk Density from igbp
• tn_igbp (g kg-1): total nitrogen from igbp
• tc_igbp (g kg-1): total carbon from igbp
• CN ratio: carbon :nitrogen ratio
• tc_hwsd (kg C m-2): total carbon from hwsd
• soc_hwsd (%): soil organic carbon from hwsd 
• soc_hwsd (g/kg): soil organic carbon from hwsd
• SM_yearly (v/v): mean annual soil moisture  
• sand (%): 
• Cden_bel (kg m-2): root carbon density
• pH:
• NPP (g m-2 yr-1): net primarily productivity
• MAP (mm): mean annual precipitation 
• MAT (deg C): man annual temperature
• clay (%):
• silt (%):
• bd_hwsd (g cm-3): bulk density from hwsd
• ST_yearly (deg C): mean annual soil temperature
• porosity_bottom: 
• porosity_midlayer:
• porosity_toplayer:
• Biome S:
• Lat F: latitude
• Long F: longitude
• Sand F:
• Silt F:
• Clay F:
• BD F:
• Porosity F:
• SM F:
• TOC g/kg F:
• SOC g/kg F:
• TN g/kg F:
• pH F:
• C/N F:
• POC Sample Type: soil type
• iPOC Total(g/kg_53-2000): POC standardized via igbp 
• hPOC Total(g/kg_53-2000): POC standardized via hwsd
• Group T: group
• POC Calcul F:
• POC Fractions:
• POC Value Type F:
• POC Covert:
• Date F:
• Depth F:
• Reference:
• Method POC_C:
• Method POC:
• Method F:

File: POC_topsoil.csv

Description: 

Variables

• ID_corri:
• NO.:
• Site:
• Country:
• bd_igbp (g cm-3):
• tn_igbp (g kg-1):
• tc_igbp (g kg-1):
• CN ratio:
• tc_hwsd (kg C m-2):
• tc_hwsd (g/kg):
• soc_hwsd (%):
• SM_yearly (v/v):
• sand (%):
• Cden_bel (kg m-2):
• pH:
• NPP (g m-2 yr-1):
• MAP (mm):
• MAT (deg C):
• clay (%):
• silt (%):
• bd_hwsd (g cm-3):
• ST_yearly (deg C):
• porosity_bottom:
• porosity_midlayer:
• porosity_toplayer:
• Biome S:
• Lat F:
• Long F:
• MAT F:
• MAP F:
• Sand F:
• Silt F:
• Clay F:
• BD F:
• Porosity F:
• SM F:
• TOC g/kg F:
• SOC g/kg F:
• TOC g/kg:
• TN g/kg F:
• pH F:
• C/N F:
• POC Sample Type:
• iPOC Total(g/kg_53-2000):
• hPOC Total(g/kg_53-2000):
• Group T:
• Flotation:
• POC Calcul F:
• POC Fractions:
• POC Value Type F:
• POC Covert:
• Treatment Type F:
• Date F:
• Depth F:
• Reference:
• Method POC_C:
• Method POC:
• Method F:
• POC-iTC:

Code/software

Engauge Digitizer software version 10.7 (http://digitizer.sourceforge.net/) 

Scikit-learn packages (version 0.23.2, https://scikit-learn.org) for Python (version 3.7.5, https://www.python.org/)

RStudio software version 4.0.3 (http://www.rstudio.com/)

ORIGIN Pro 2023 (http://www.originlab.com/)

ArcGIS software (version 10.8, ESRI, Redlands, CA)