Roots take up water and nutrients from the soil, they store carbon compounds, and they provide physical stabilization. We investigate how the subterranean plant parts influence the forest ecosystem.
While the fine roots (roots with a diameter below 2 mm) are evident in the uptake of water and nutrients, both fine and coarse roots (roots with a diameter of 2 mm and above) are relevant in tree stability. Our research delivers an important contribution to the biology and ecology of tree roots, and the results support science as well as extension and teaching. Our aim is the support of the sustainability of forest ecosystems.
Roots - the hidden half
Roots take up water and nutrients from the soil, they store carbon compounds, and they provide physical stabilization. While the fine roots (roots with a diameter below 2 mm) are evident in the uptake of water and nutrients, both fine and coarse roots (roots with a diameter of 2 mm and above) are relevant in tree stability. Furthermore, fine roots of trees undergo constant replacement in root turnover and provide a large biomass input to the soil containing both carbon and mineral nutrients. Hence fine roots are important in carbon fluxes to soils and in carbon storage in soils, as well as in below-ground recycling of nutrients such as nitrogen, phosphorus, magnesium and calcium.
55 tons of roots per hectare forest soil
Estimations from temperate forests in Central Europe showed that about 52 t/ha are coarse tree roots and 2.5 t/ha are fine tree roots. Thus, about one third of the forest stands biomass are roots. Because tree roots are in an intimate contact with their surrounding soil, they somehow reflect the soils chemical and physical properties and conditions. Roots are also able to react to changes in soils with morphological, physiological, and molecular alterations. Therefore, tree roots can be used as indicators.
- Development of suitable and reliable methods and tools in order to identify and characterize tree roots.
- Investigation of morphological, physiological, biochemical, and molecular root parameters as reactions to ecological adverse soil conditions such as acidification, eutrophication, high heavy metal contents, drought, elevated temperatures, or compaction.
- Assessment of the contribution of tree roots to the forest soil carbon pools and fluxes, hence to develop and apply methods for improved estimations of root production, mortality, turnover, and decomposition.
- Improvement of physiological, biochemical and molecular methods for the investigation of tree roots of small sample amounts.
- Recording the distribution of tree roots in forest soils, estimation of their impacts on soil functions, e.g. soil stability and soil water properties, and improvement of their services to the sustainability of the forest ecosystems.
Identification of tree roots
With the aid of a genetic fingerprinting method, roots of the most common 30 forest tree species of Central Europe can be identified relative easily. If shrubs or exotic tree species are involved, then the genetic code needs to be sequenced, which is more labor-intensive (see Article of the "Info-Blatt Wald" from 2001: "Identifizierung von Baumwurzeln – eine kriminalistische Kleinarbeit", in German).