Project title: Soil Biodiversity and Functioning of Agricultural Ecosystems: Developing Science for Evidence Based Policy
Applicants: Prof. Dr. Marcel van der Heijden, Forschungsanstalt Agroscope Reckenholz-Tänikon ART, Zurich; Prof. Dr. Bernhard Schmid, University of Zurich, Zurich.
Soil microbes represent the unseen majority of life on Earth and are essential for the functioning of terrestrial ecosystems as they catalyse unique and indispensable transformations in the biogeochemical cycles of the biosphere. The significance of soil microbial diversity for the functioning of agricultural and natural ecosystems is still poorly understood and soil microbial communities can be considered as a black box. Unravelling what soil microbes are doing in this black box has been identified as one of the major research areas in science, comparable to the search for life on Mars. The significance of microbial diversity for the functioning of agro-ecosystems will be investigated in this project.
The central hypotheses are:
1) Soil biodiversity enhances plant productivity, nutrient acquisition, plant diversity and decomposition. 2) Resource use and uptake by plants and soil biota is more effective when soil biodiversity is high because different soil organisms complement each other via their differences in soil nutrient requirements, and ability to store nutrients and transferring them to plants. 3) Soil microbial communities from grassland and organically managed fields are more diverse and are better able to support crop production under standardized conditions relative to microbial communities from conventionally managed fields with high fertilizer and pesticide input. 4) Enhanced abundance of particular functional groups in organically managed fields increases sustainability by reducing nutrient losses and recycling nutrients more effectively.
To test these hypotheses, experimental ecosystems will be constructed under controlled conditions and soil biodiversity will be manipulated. Moreover, the presence and composition of specific microbial groups (fungi, bacteria, mycorrhizal fungi) will be manipulated and their effects upon plant productivity, plant diversity and ecosystem functioning will be investigated. The microbial groups used for these manipulative experiments will be selected based upon a large-scale field survey using state of the art sequencing techniques to explore whether soil microbial diversity and composition and the abundance of specific microbial groups differs between various agricultural practices.
Potential Results and Significance:
This research will show whether it is beneficial to have high soil biodiversity in agro-ecosystems and whether the stimulation of soil biodiversity can enhance ecosystem sustainability.