Haojie Liu - Academia.edu (original) (raw)
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Spatial variability of soil properties is important for hydrological studies. However, little inf... more Spatial variability of soil properties is important for hydrological studies. However, little information is available on the spatial variability of hydro-physical properties of peat soils. Three study sites: natural, degraded and extremely degraded peatland were selected for this study. At each site, 72 undisturbed soil cores were collected from 5m by 5m grid cells in an area of 40m by 45m. The saturated hydraulic conductivity (Ks), soil water retention curves, total porosity, macroporosity, bulk density and soil organic matter (OM) content were determined for all sampling locations. The van Genuchten model parameters (θs, α, 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 for the different sites. The soil physical properties (e.g. OM content and bulk density) exhibited different levels of spatial autocorrelation depending on the soil degradation stage. The cross-semivariograms showed a strong or moderate spatial dependency between soil physical properties and van Genuchten model parameters. The more a peat soil is degraded, the more likely it is that soil physical properties are spatially dependent. In conclusion, degradation stage plays an important role and should be considered more often in spatial analysis. The obtained cross-semivariogram may serve as a basis for 2D and 3D hydrological modelling.
Peatlands have been drained for land use for a long time and on a large scale, turning them from ... more Peatlands have been drained for land use for a long time and on a large scale, turning them from carbon and nutrient sinks into respective sources, diminishing water regulation capacity, causing surface height loss and destroying biodiversity. Over the last decades, drained peatlands have been rewetted for biodiversity restoration and, as it strongly decreases greenhouse gas emissions, also for climate protection. We quantify restoration success by comparing 320 rewetted fen peatland sites to 243 near-natural peatland sites of similar origin across temperate Europe, all set into perspective by 10k additional European fen vegetation plots. Results imply that rewetting of drained fen peatlands induces the establishment of tall, graminoid wetland plants (helophytisation) and long-lasting differences to pre-drainage biodiversity (vegetation), ecosystem functioning (geochemistry, hydrology), and land cover characteristics (spectral temporal metrics). The Paris Agreement entails the rewetting of 500,000 km 2 of drained peatlands worldwide until 2050-2070. A better understanding of the resulting locally novel ecosystems is required to improve planning and implementation of peatland rewetting and subsequent management.
Frontiers in Environmental Science
Spatial variability of soil properties is important for hydrological studies. However, little inf... more Spatial variability of soil properties is important for hydrological studies. However, little information is available on the spatial variability of hydro-physical properties of peat soils. Three study sites: natural, degraded and extremely degraded peatland were selected for this study. At each site, 72 undisturbed soil cores were collected from 5m by 5m grid cells in an area of 40m by 45m. The saturated hydraulic conductivity (Ks), soil water retention curves, total porosity, macroporosity, bulk density and soil organic matter (OM) content were determined for all sampling locations. The van Genuchten model parameters (θs, α, 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 for the different sites. The soil physical properties (e.g. OM content and bulk density) exhibited different levels of spatial autocorrelation depending on the soil degradation stage. The cross-semivariograms showed a strong or moderate spatial dependency between soil physical properties and van Genuchten model parameters. The more a peat soil is degraded, the more likely it is that soil physical properties are spatially dependent. In conclusion, degradation stage plays an important role and should be considered more often in spatial analysis. The obtained cross-semivariogram may serve as a basis for 2D and 3D hydrological modelling.
Peatlands have been drained for land use for a long time and on a large scale, turning them from ... more Peatlands have been drained for land use for a long time and on a large scale, turning them from carbon and nutrient sinks into respective sources, diminishing water regulation capacity, causing surface height loss and destroying biodiversity. Over the last decades, drained peatlands have been rewetted for biodiversity restoration and, as it strongly decreases greenhouse gas emissions, also for climate protection. We quantify restoration success by comparing 320 rewetted fen peatland sites to 243 near-natural peatland sites of similar origin across temperate Europe, all set into perspective by 10k additional European fen vegetation plots. Results imply that rewetting of drained fen peatlands induces the establishment of tall, graminoid wetland plants (helophytisation) and long-lasting differences to pre-drainage biodiversity (vegetation), ecosystem functioning (geochemistry, hydrology), and land cover characteristics (spectral temporal metrics). The Paris Agreement entails the rewetting of 500,000 km 2 of drained peatlands worldwide until 2050-2070. A better understanding of the resulting locally novel ecosystems is required to improve planning and implementation of peatland rewetting and subsequent management.
Frontiers in Environmental Science