The impact of root growth and arbuscular mycorrhizal functional interactions for the acquisition of heterogeneous distributed nutrients in the initial stage of soil development.

• Applicant: Dr. Katja Boldt-Burisch
• Subject Area: Soil Sciences ; Microbial Ecology and Applied Microbiology ; Ecology and Biodiversity of Plants and Ecosystems ; Plant Cultivation, Plant Nutrition, Agricultural Technology
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 263324268

The incipient colonization of soils of initial ecosystems is dominated by pioneer plants that need both, accomplish building their supply infrastructure by development of root systems and by decomposition of nutrient elements which are bound in the initial substrate. The construction of previously named structures for storage and retrievability of nutrient resources is also a key function in the initial phase of soil development, since the establishment of an efficient nutrient balance creates the basis for the development of mycorrhizae and soil bacteria and in turn, improves the nutrient supply infrastructure of plants. Distribution of soil nutrients can be very small-scale heterogeneous, especially in initial soils. In this context, the ability of plants to adapt to locally increased nutrients and to acquire these nutrients (precision root foraging) is highly variable. So far, the relationship between distribution of soil nutrient resources and impact of the functional interaction between root growth and arbuscular mycorrhizal fungi for nutrient uptake is largely unknown. The aim of the project is to investigate relevant connections between heterogeneous distributed soil nutrients and distribution of spores and hyphae, respectively the activity of AM fungi in relation to the precision root foraging behavior of plants. Based on field experiments diversity of fungal spores of AM-fungi in the initial substrate will be investigated. Experiments will provide data about which influence stand age of various plant species has on the spatial distribution of AM fungi in the soil, what differences occur on these parameters by the seasonal influence and whether acquisition of heterogeneously distributed nutrients is associated with an increased AM-infection potential. On the basis of rhizotron experiments interactions between nutrient distribution, AM-fungal distribution and root growth will be observed over a certain period of time. These experiments will provide detailed information about whether a heterogeneous distribution of nutrients cause a precision root foraging reaction even without the presence of arbuscular mycorrhizal fungi and will provide results about the effect of different distribution of spores in soil on the uptake of nutrients. Answering of these questions will contribute to a better understanding of dominant, primary nutrient acquisition in the early phase of soil development and basic nutrient cycle in ecosystems in general and provide valuable information for biologically based approaches to land reclamation.

• DFG Programme: Research Grants