Global change effects on forest understorey: how do interactions between drought and land-use intensity affect water, carbon and nitrogen cycling?
In this project, canopy structures will be established in forest areas to observe biogeochemical and hydropedological processes in response to reduced precipitation and their interaction with forest use type, forest undergrowth diversity and soil biota. Climatic influences as well as effects of soil structure and soil hydrological functions on the water and carbon balance of plant species and communities along a land- use and biodiversity gradient will be investigated.
- How does climate affect biodiversity influenced by ecosystem function and structure?
- Does higher biodiversity increase the resilience potential of ecosystems to climate/weather extremes?
- What are the relationships between land- use, biodiversity and ecosystem processes under climate change
1. Reduced precipitation affects evaporation and productivity.
2. Drought changes the hydraulic functions of the soil.
3. Soil dryness leads to a biotic feedback on soil hydrological properties.
4. Reduced precipitation influences plant rooting and nutrient uptake.
5. Water and nutrient feedback cycles should be integrated into an understory growth model.
In this project phase, the experiment is established and the first three hypotheses take centre stage.
A central roof (10x10m) and 4 smaller roofs (3x3m) will be built on 3 forest EPs in each exploratory and control areas of the same size will be set up.
In the first work package by Prof. Dr. Bruelheide, Dr. Welk and Mr. Baudis (University of Halle), transpiration rates and the productivity of plants are measured.
In the second work package by Prof. Dr. Weiler and Dr. Puhlmann (University of Freiburg), the hydraulic functions of the soil are investigated using fluorescence tracers, chromatography, root counting, mass spectrometry and laser absorption spectrometry to determine stable isotope contents.
In the third work package by Dr. Gessler, Dr. Ulrich, Dr. Kayler and Dr. Ellerbrock (ZALF, Müncheberg), the water and carbon cycle and effects on soil microbes are investigated. The diversity of soil microorganisms is recorded using molecular fingerprints and sequencing. Soil water repellency is measured using infrared spectrometry.