Digital soil mapping to improve knowledge of soil-water relationships in Scotland

"This information is crucial for the sustainable management of water and land, especially under a changing climate where drought periods are expected to become more frequent and extensive"

Soils delay runoff, store and redistribute water and provide a supply of moisture for plant growth. These soil functions are fundamental for the understanding of how pollutants travel from land to waters and to evaluate ecosystem services. Dr Zisis Gagkas, a Macaulay Development Trust research fellow based within the James Hutton Institute in Aberdeen, is developing digital soil mapping techniques to help produce maps that can be used in land and environmental risk assessments such as to inform Scotland’s natural flood management measures and reduce flood risk.

Decision makers increasingly need maps that are spatially explicit and at finer spatial resolutions. Digital soil mapping provides the most appropriate tools for producing maps that can meet these demands, by combining statistical and geospatial analysis. Currently, the application of various biophysical resource tools that require soil hydrological information to large parts of Scotland is restricted due to the coarse resolution of the available soil map, coupled with the unknown location of multiple soil types present in some of the more complex landscapes.

Dr Gagkas explains: “By using digital soil mapping, we can improve our understanding of soil processes and produce soil maps at a range of spatial resolutions with an estimate of predicted uncertainty.

“My research examined different digital soil mapping and other numerical techniques to predict and map the rate of water movement through soils and the capacity of Scottish soils to retain water that is available to plants, generally referred as the soil's available water capacity. This information is crucial for the sustainable management of water and land, especially under a changing climate where drought periods are expected to become more frequent and extensive.”

Results showed that applying digital soil mapping techniques to Hutton soils data allows for land evaluations based on more dynamic, statistical approaches - an improvement over traditional expert opinion-based methods.

These digital soil assessments can be further combined with other types of data (e.g. environmental, socio-economical) to help address some of the world's most challenging problems including the impact of climate change on ecosystems and threats to food and water security.

Dr Gagkas said that his Macaulay Development Trust fellowship gave him a unique opportunity for personal development by gaining new and valuable skills and expertise within the fields of digital soil mapping and hydropedology.

“This experience has enabled me to advance my career in digital soils research with regards to developing new methods and tools for mapping soils and waters.

“My next challenge is to find new and innovative ways for integrating digital soil mapping products within frameworks and tools that can be used to facilitate a more integrated and sustainable management of land and water resources in Scotland and beyond.”

To learn more about Dr Gagkas’ research, visit his staff page.