- 1University of Rostock, Faculty of Agricultural and Environmental Sciences, Soil Physics, Germany (ji.qi@uni-rostock.de)
- 2Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, Ontario, Canada (frezanez@uwaterloo.ca)
- 3Cold Regions Research Centre, Wilfrid Laurier University, Waterloo, Ontario, Canada (wquinton@wlu.ca)
- 4Department of Ecoscience, Aarhus University, Aarhus, Denmark (doz@ecos.au.dk)
- 5Botany, School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland (saahmad@tcd.ie)
- 6School of Geographical Sciences, Nanjing University of Information Science & Technology, Nanjing 210044, China (lx.wang@nuist.edu.cn)
- 7College of Resources and Environmental Engineering, Ludong University, Yantai 264025, China (yzhaosoils@gmail.com)
Abstract
The hydro-physical properties of peat play a pivotal role in regulating the water, nutrient, and carbon cycles of peatland ecosystems. Despite their importance and complexity, our understanding of peat hydraulic properties remains limited. In this study, we compiled a comprehensive global database of the peat physical, hydraulic, and chemical properties, including bulk density (BD), porosity, macroporosity, saturated hydraulic conductivity (Ks), carbon content, and carbon density, encompassing tropical peatlands, northern fens, northern bogs, and permafrost regions. Our primary objective was to examine how these properties vary along a BD gradient across different climate zones. The results revealed a robust linear relationship between carbon density and BD for peat types with carbon content exceeding 35% (R2> 0.92, p < 0.001), suggesting that these functions can serve as reliable tools for estimating the carbon stock of peatlands. However, the specific functions differed between peat types and climate zones. Total porosity was found to decrease linearly as BD increased, while macroporosity followed a power-law relationship with BD. These trends were consistent across all peat types, underscoring a strong and reliable association between BD and both total porosity and macroporosity. Additionally, Ks exhibited a general decline with increasing BD, with the relationship characterized by log-log functions that varied among peat types and climate zones. This indicates that Ks is significantly influenced by the peat-forming vegetation such as wood, sphagnum, sedge, and the prevailing climatic conditions of the peatland. This study demonstrated that the key peat hydro-physical-chemical parameters—including carbon density, porosity, macroporosity, and Ks can be reliably estimated using the BD, with relatively high coefficients of determination (R2 > 0.4), highlighting the critical importance of determining BD as a proxy for estimating other hydro-physical properties of peat when direct measurements are unavailable.
Keywords: peat; physical and hydraulic properties; bulk density; carbon density; saturated hydraulic conductivity, permafrost peatlands
Corresponding author: Haojie Liu (haojie.liu@uni-rostock.de)
Phone: +49 (381) 498 3193; Fax: +49 (381) 498 3122
How to cite: Qi, J., Weigt, S., Wang, M., Rezanezhad, F., Quinton, W., Zak, D., Ahmad, S., Wang, L., Zhao, Y., Lennartz, B., and Liu, H.: Hydraulic Functions of Peat Across Types and Climate Zones, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6587, https://doi.org/10.5194/egusphere-egu25-6587, 2025.
