Journalartikel

Jahr der Veröffentlichung: 2021

Zeitschrift: Geoderma

Bandnummer: 399

ISSN: 0016-7061

eISSN: 1872-6259

Open Access Status: Hybrid

DOI Link: https://doi.org/10.1016/j.geoderma.2021.115123

Verlag: Elsevier

Abstract: 
The spatial variability of soil properties plays an important role in water and carbon cycles in peatlands. The objectives of this study were to analyze the spatial variation of hydro-physical properties of peat soils and to establish pedotransfer functions (PTFs) to estimate the hydraulic properties of peat using readily available soil properties. We selected three study sites, each representing a different state of peat degradation (natural, degraded and extremely degraded). At each site, 72 undisturbed soil cores were collected from 5 m by 5 m grid cells in an area of 35 m by 40 m. The saturated hydraulic conductivity (Ks), soil water retention curves, total porosity, macroporosity (pore diameter >30 mu m), bulk density and soil organic matter content (SOM) were determined for all sampling locations. The Van Genuchten (VG) model parameters (theta(s), alpha, and n) were optimized using the RETC software package. A strong positive correlation between macroporosity and Ks was observed irrespective of the degradation stage of the peat. However, the relationships between macroporosity and Ks differed between the natural and the drained peatlands. Adding macroporosity to the PTFs substantially improves the prediction of K-s as well as VG parameters. Results show that the soil physical and hydraulic properties (e.g. K-s and VG model parameters) exhibit different levels of spatial heterogeneity depending on the peat degradation stage. The geostatistical analysis suggests that the spatial dependence of soil hydro-physical properties varies depending on the considered property as well as land management (e.g. drainage). Bulk density and SOM are spatially dependent, whereas K-s and macroporosity are spatially independent if the peat is severely degraded. In conclusion, the peat degradation stage plays an important role and should be generally considered in the spatial analysis of peatlands. The obtained semivariograms may serve as a basis for 2D and 3D hydrological modelling as well as peatland restoration studies.

Harvard-Zitierstil: Wang, M., Liu, H. and Lennartz, B. (2021) Small-scale spatial variability of hydro-physical properties of natural and degraded peat soils, Geoderma, 399, Article 115123. https://doi.org/10.1016/j.geoderma.2021.115123

APA-Zitierstil: Wang, M., Liu, H., & Lennartz, B. (2021). Small-scale spatial variability of hydro-physical properties of natural and degraded peat soils. Geoderma. 399, Article 115123. https://doi.org/10.1016/j.geoderma.2021.115123