Connecting the green and the grey world – an experimental approach to separating climate, vegetation and geochemical effects on nutrient cycling along a climate gradient

 

Investigator Names and Contact Info:

• Katja Tielbörger (Plant Ecology). Plant Ecology Group, Institute of Evolution and Ecology, University of Tuebingen, Germany
• Yvonne Oelmann (Geoecology-Biogeochemistry). Geoecology, Geography, University of Tuebingen, Germany
• Harald Neidhardt (Geoecology). Geoecology, Geography, University of Tuebingen, Germany

 

Chilean Collaborators Involved:

• Lohengrin Cavieres. Dept. Botánica, Universidad de Concepción, Chile

 

An experimental approach to separating climate, vegetation and geochemical effects on nutrient cycling along a climate gradient

 

PhD-Student:

• Liesbeth van den Brink. University of Tuebingen, Germany

Supervisors: Prof. Katja Tielbörger, Prof. Yvonne Oelmann, Dr. Lohengrin Cavieres

 

 

Foliar litter decomposition along a climatic gradient.

MSc-Student:

• Timo Knüver. University of Tuebingen, Germany

Supervisor: Prof. Yvonne Oelmann, Co-Supervisor: Dr. Harald Neidhardt

 

Characterization of nutrient limitation to soil microbial activity along a Chilean climatic gradient.

 

MSc-Student:

• Lorena Mattes. University of Tuebingen, Germany

Supervisor: Prof. Yvonne Oelmann

 

Impact of drought on plant available nutrients in soils along a Chilean climatic gradient.

 

MSc-Student:

• Florian Hofmann. University of Tuebingen, Germany

Supervisor: Prof. Yvonne Oelmann, Co-Supervisor: Dr. Haraldt Neidhardt

 

 

Distribution of halogens (Cl, Br, F, I) in soils and plants along a climate gradient of the Chilean Coastal Cordillera.

 

MSc-Student:

• Erik Lemke. University of Tuebingen, Germany

Supervisor: Prof. Yvonne Oelmann, Co-Supervisor: Dr. Harald Neidhardt

 

 

Impact of herbivory on foliar nutrient concentrations in an arid and semiarid environment of Chile.

 

MSc-Student:

• Laura-Nadine Korbacher. University of Tuebingen, Germany

Supervisor: Prof. Yvonne Oelmann, Co-Supervisor: Prof. Katja Tielbörger

 

 

Herbivorous Damage Along a Latitudinal Climate Gradient in Chile.

 

BSc-Student:

• Rebecca Peters. University of Tuebingen, Germany

Supervisors: Prof. Katja Tielbörger, Prof. Yvonne Oelmann

 

 

Project Summary:

The objective of our project is to combine plant ecological with biogeochemical expertise and methodology for investigating how the relative importance of geochemical and biological processes for geo-biosphere feedbacks change in response to climatic conditions. Therefore, we combine the space-for-time approach with mechanistically orientated field experiments that directly manipulate environmental conditions along a climatic gradient in Chile. With this approach, we aim to address the following overarching questions: Can space substitute for time, and which temporal processes can be better described by a space-for-time approach than others? What is the role of biotic processes in determining the predictability of bio-geo dynamics? Under which circumstances can spatial climate gradients, i.e. the result of long-term climatic impact on the earth surface, serve as proxy for short- to medium term temporal climatic changes? As a side effect, our study will be the first in Chile to investigate the impact of concurrent climate change on ecosystem processes by means of large-scale field experiments. To that end, we will apply a novel approach designed for biological climate impact studies to describe biogeochemical interactions along the climatic gradient of the EarthShape focus areas. Our overall objectives align perfectly with the objectives of EarthShape in bridging between the biological and geological sciences. We apply a truly integrated approach to studying the relationships between the green (plants), the brown (soil) and the grey (parent rock) world, by pairing investigators with extensive experience in the fields of biogeochemistry and plant ecology. In addition, our experimental approach enables to bridge across a range of spatio-temporal scales, ranging from single years (i.e. growing seasons) to very long time scales relevant for geological processes. In the current phase of the SPP, we plan to focus on rapid and fast responses of the plants and of processes in soil potentially influenced by these changes (plant-soil feedbacks). In subsequent phases, we will be able to add a longer-term perspective on these plant-soil feedbacks, in particular encompassing soil processes that may respond to climate variation with a time lag. In terms of specific objectives, our project addresses two of the original EARTHSHAPE hypotheses and contributes to Cluster II, investigating the bio-mediated redistribution of material within the weathering zone. In addition, our project reaches out to the other clusters and generates process knowledge that is useful for future modelling activities (s. chapter 6).