Uni-Bayreuth grafik-uni-bayreuth



Spatial analysis of soil related environmental risks in the Soyang Lake Watershed

TERRECO Cluster F-02

From 10/2012 to 07/2013

Principal Investigator: Bernd Huwe, Mareike Ließ, Soo Jin Park
Staff: Hannes Oeverdieck

Abstract: The complex interaction of soil forming factors activates particular soil forming processes which lead to characteristic soil properties. Soils on hillslopes are related to one another by hillslope processes, i.e., surface and subsurface flow, erosion and landslides. Digital soil maps will be developed regarding physical soil parameters such as soil cohesion, soil texture, bulk density, water retention and saturated hydraulic conductivity to estimate the spatial distribution of environmental risks.

Methods from the field of statistical learning theory, e.g., recursive partitioning algorithms, linear regression or artificial neural networks, are often applied to develop digital soil maps (DSM). Continuous environmental variables, such as terrain parameters calculated from a digital terrain model (DTM), information derived from remote sensing data (vegetation indices, land use / land cover, climate) as well as geological maps are used as prediction parameters to extrapolate soil information from point data.

To obtain a representative dataset for the Soyang Lake Watershed, a stratified sampling design will be developed, taking regional constraints such as the area’s accessibility and land mine no-go areas into account. The impact of smoothing of the DTM derived terrain parameters on the DSM will be investigated as well as the sensitivity of DSM predicted soil parameters regarding soil erosion, debris slides and landslide source areas. An area specific pedotransfer function will be developed to estimate soil hydraulic conductivity and compare its accuracy to already existing pedotransfer functions.

The spatial risk will be analysed together with nutrient, sediment and debris transport to Soyang Lake to understand the impact on water quality and the dam’s efficiency to generate energy, land and water use policies, and the general vulnerability of the Soyang Lake watershed.

Key words: risk assessment, physical soil properties, sensitivity analysis, pedotransfer function, digital soil mapping


Poster January 2013

last modified 2014-09-27