Abstract
Dissolved carbon (C) leaching in and from soils plays an important role in C transport along the terrestrial-aquatic continuum. However, a global overview and analysis of dissolved carbon in soil solutions, covering a wide range of vegetation types and climates, is lacking. We compiled a global database on annual average dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in soil solutions, including potential governing factors, with 762 entries from 351 different sites covering a range of climate zones, land cover types and soil classes. Using this database we develop regression models to calculate topsoil concentrations, and concentrations versus depth in the subsoil at the global scale. For DIC, the lack of a proportional globally distributed cover inhibits analysis on a global scale. For DOC, annual average concentrations range from 1.7 to 88.3 (median = 25.27) mg C/L for topsoils (n = 255) and from 0.42 to 372.1 (median = 5.50) mg C/L for subsoils (n = 285, excluding lab incubations). Highest topsoil values occur in forests of cooler, humid zones. In topsoils, multiple regression showed that precipitation is the most significant factor. Our global topsoil DOC model (R 2= 0.36) uses precipitation, soil class, climate zone and land cover type as model factors. Our global subsoil model describes DOC concentrations vs. depth for different USDA soil classes (overall (R 2= 0.45). Highest subsoil DOC concentrations are calculated for Histosols.
| Original language | English |
|---|---|
| Article number | 1626 |
| Number of pages | 21 |
| Journal | SN Applied Sciences |
| Volume | 2 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 4 Sept 2020 |
Bibliographical note
Funding Information:This research was funded by the NWO New Delta 2014 project no. 869.15.015. W.J.H was funded by the NWO New Delta 2014 project no. 869.15.014. A.F.B. and A.H.W.B. received support from the PBL Netherlands Environmental Assessment Agency through in-kind contributions to The New Delta 2014 ALW projects no. 869.15.015 and 869.15.014. L.V. was funded by the Earth and life sciences (ALW) Open Programme 2016 project no. ALWOP.230 We are grateful to Marta Camino-Serrano (Centre for Ecological Research and Forestry Applications, CREAF) for providing us with a list of several studies to include in the database, which we acknowledge her by mentioning it in the database references concerned. We further thank Peter Janssen (PBL) and Maarten Zeylmans Van Emmichoven (Physical Geography - UU) for assisting in the analysis design and data extraction from maps respectively.
Publisher Copyright:
© 2020, The Author(s).
Funding
This research was funded by the NWO New Delta 2014 project no. 869.15.015. W.J.H was funded by the NWO New Delta 2014 project no. 869.15.014. A.F.B. and A.H.W.B. received support from the PBL Netherlands Environmental Assessment Agency through in-kind contributions to The New Delta 2014 ALW projects no. 869.15.015 and 869.15.014. L.V. was funded by the Earth and life sciences (ALW) Open Programme 2016 project no. ALWOP.230 We are grateful to Marta Camino-Serrano (Centre for Ecological Research and Forestry Applications, CREAF) for providing us with a list of several studies to include in the database, which we acknowledge her by mentioning it in the database references concerned. We further thank Peter Janssen (PBL) and Maarten Zeylmans Van Emmichoven (Physical Geography - UU) for assisting in the analysis design and data extraction from maps respectively.
Keywords
- Carbon leaching
- Database
- DIC
- DOC
- Global model
- Soil carbon
- Soil solution
- Vadose zone
