Hannu Marttila, Tapio Tuukkanen & Bjørn Kløve
Proceedings of the 14th International Peat Congress
degree-of-humification, erosion, peat-mining, peatland, soil-properties
Theme II. Peat for horticulture, energy and other uses
Active peat mining is carried out in circa 60 000 ha in Finland. Drainage and production operations enhance the peat soil properties and expose bare peat to weathering forces, and further release elements to water courses. The erosion rate at production surfaces is mainly controlled by climate conditions and peat soil properties. However, earlier studies have scarcely investigated the effect of the varying characteristics of the peat layers to erosion rate. To study this phenomenon, we took peat core samples (1m depth, 2 replicates) from 15 peat mining sites across Finland. Peat soil and hydraulic properties from different layers (10 cm slices) were measured in detail in the laboratory. Further, critical shear stress and erosion rate was determined using a cohesive strength meter instrument. This paper (and oral presentation) presents preliminary results from this study with a special focus on the effect of humification on erosion. Potential differences of peat deposits and their effect on contributing to the load to water courses are discussed.