Subproject Fauna
Functional impact of soil animals on urban soils
Prof. Dr. Gerd Weigmann, Dr. Silvia Pieper
Aim of the subproject FAUNA is to identify and characterize the impact of soil faunal activity on turnover processes in urban soils. Next to the estimation of the soil animal functional contribution to the processes of nutrient release and chemical transport in soils, in this second project phase particular attention will be paid to the study of the interrelationships between soil faunal activity and spatially heterogenous soil properties of urban sites.
The results achieved in the first project phase show the importance of the activity of soil animals for the decomposition of organic matter in our experimental urban field sites. In particular, the produced faunal-specific organic structures such as faeces or mucus display characteristic deviations - compared to the parent litter or the soil organic matrix - concerning the quality of the organic matter and the concentrations of nutrients and pollutants.
Soil animals have a species-specific impact on the release pattern of nutrients and pollutants from litter and soil and they modulate in time the composition of the soil solution, as could be demonstrated in microcosm experiments of increasing complexity.
The outcome of field studies of the INTERURBAN group points to the importance of the spatial distribution of heterogenous soil properties such as hydrophobicity for the transport of water and matter through preferential flow in soils.
It will be therefore of particular interest for us in this second phase of the project to understand how soil animal species and their activities may interact with the emergence and persistence of hydrophobic soil patches and the mobilization of nutrients/pollutants from urban soils. Especially, the upgrading from a laboratory investigation scale to field surveys is approached through the set up of field mesocosms, where the burrowing activity of soil animals and the mixing of soil particles with excretion products shall modify the structure of the soil horizons in a relevant scale for the investigated parameters.
Staff:
Prof. Dr. Gerd Weigmann
Dr. Silvia Pieper
Friedemann Linsler
Susann Trautmann
Jörg Schaller