Features Related to Faunal Activity

Kooistra, M.J.; Pulleman, M.M.


Soil fauna plays an important role in transporting and altering various soil components, in particular the decomposition of organic matter and the development of soil structure. Fauna-induced features are found in all types of soils and can be so abundant that they determine the nature and intensity of active physical and chemical processes. However, there is still a lack of knowledge of the impact of soil fauna on soils. Micromorphological techniques provide an excellent tool to understand the role of soil animals and their impact on an array of soil properties. This chapter presents a basic outline of the diversity of faunal features recognized in soil thin sections. The first part deals with the variety of void systems produced by soil fauna, such as channels, chambers and modified voids. The second part presents a review of pedofeatures produced by soil fauna, including different types of excrements, coatings and infillings. Each group of faunal species produces a number of different features related to various factors, such as mobility, food source, life cycle phase, body size, soil composition and moisture status, all commonly with important seasonal variations. One group alone, for example termites, earthworms or molluscs, can produce over 50 different kinds of features, with varying effects on soils. Important applications of micromorphological studies of features related to faunal activity are mainly related to soil formation and humus development, landscape reconstruction, archaeology and faunal impact on soil functions as affected by soil management