Aims of InterUrban
Objective
Clarification of the dynamics of water and materials at urban locations with special consideration of the Spatial heterogeneity, the organic soil substance, and soil-biological transformation processes.
In order to achieve this goal, four interdisciplinary questions will be treated.
- Evaluation of spatial heterogeneity and its interaction with sub-processes (subprojects SOIL, MOBIL, GEO and FAUNA)
- Influence of biotic and abiotic factors on the characteristics of the organic substance (subproject MIKRO, HUMUS, FAUNA and COLLOID).
- Recording of water- and material transport from heterogeneous urban locations and appliance to an area (subproject SOIL, GEO and MOBIL).
- Recording of the interaction between biotic and abiotic factors and their participation in the dynamics of the release of pollutants
System comprehension: Dynamics of water and materials at urban locations
Most of the urban soils have a comparatively low age, large developmental dynamics, and are marked by a high variability in small areas. Additionally, larger alterations of the environmental conditions (water-, material-, and heat budget) occur compared to near-natural areas. Therefore, the central questions of this research group are the water- and material transport, spatial variability, as well as changes in the topsoil. The main objective of the research group is to characterize the conversion-processes at urban locations and to evaluate the transport of material. To achieve this goal, a further development and a combined application of new methods as well as an analysis of interdisciplinary interactions is necessary.
Detailed field- and laboratory experiments of all special fields involved on two intensive areas are planned for the first phase of the project. Special emphasis is given to the following four questions:
- Recording and revealing the causes of the small area-variability of soil characteristics and their interactions to other processes.
- Influence of biotic and abiotic factors on characteristics of the organic substance.
- Analysis of water- and material transport of heterogeneous sites and application to an area.
- Characterisation of the interaction between biotic and abiotic Factors and their effect on the Dynamics of the release of pollutants.
The possibilities and limits of different geophysical methods in combination with soil-physical methods will be examined in particular. Coordinated evaluations of soil chemistry, microbiology, and soil zoology will be carried out in order to characterize material transformation. In the course of these evaluations, special consideration is give to soil moisture and the hydrophobicity.
The emphasis of the laboratory experiments was put on the analysis of processes. This involves characterizing the organic soil substance regarding to the physical structural characteristics (colloid-, gel-, glass-structures), their temporal changes, as well as investigations of the effect of interrelations on the material transport i.e. on the mobilization of pollutants.
The implementation of experiments on microcosms combined with narrow analyses of soil horizon differentiation at screening points in a terrain is meant to facilitate a) a clarification of the interaction between soil animals and microbial colonization, b) an analysis of the involvement of material conversion and mobilization, and c) a relation to areas.
In the second stage of the project (years 4-6), the gained knowledge will be used for a further development of existing numeric simulation models, in order to enable prognoses on developments of locations and the leaching of materials. The developed methods and techniques are supposed to be tested regarding their applicability to other locations (regionalization).
