Plant-microbe interactions; Plant growth; Drought; Radiocarbon; Stable isotope tracing; Soil biogechemistry; Illumina sequencing; Pinus sylvestris; Tree mortality
Ofiti Nicholas O.E., Zosso Cyrill U., Soong Jennifer L., Solly Emily F., Torn Margaret S., Wiesenberg Guido L.B., Schmidt Michael W.I. (2021), Warming promotes loss of subsoil carbon through accelerated degradation of plant-derived organic matter, in
Soil Biology and Biochemistry, 156, 108185-108185.
Solly Emily F., Weber Valentino, Zimmermann Stephan, Walthert Lorenz, Hagedorn Frank, Schmidt Michael W. I. (2020), A Critical Evaluation of the Relationship Between the Effective Cation Exchange Capacity and Soil Organic Carbon Content in Swiss Forest Soils, in
Frontiers in Forests and Global Change, 3(98), 1-12.
Forest ecosystems cover approximately 30% of Earth’s land surface and provide innumerable ecosystem services, yet they are vulnerable to climate extremes. Of particular concern are the potential increases in tree mortality associated with drought-induced physiological stress. In parallel to the widespread reductions in tree growth and increased mortality which have been documented in most bioregions as a response to drought, the impact of water limitation on the soil microbiome likely have prominent effects on the cycling of carbon and nitrogen in forest ecosystems. Here we propose to simultaneously assess the currently little explored mechanistic responses of trees and microbial communities exposed to different levels of drought under controlled conditions, and to determine how the interactive effects of these responses influence the dynamics of carbon and nitrogen in forest soils. The proposed project aspires to create a novel, predictive framework founded on the principles that i) trees and microbial communities respond to altered environmental conditions in order to optimize their resource availability, and ii) that the interactive effects of these responses have a key influence on soil biogeochemistry and soil organic carbon storage. To reach these objectives we will adopt a multidisciplinary and multiscale approach combining mesocosm experiments under control conditions and field studies in drought-affected mature forests. Cutting edge methodologies such as high-throughput DNA and RNA sequencing will be implemented to study the long-term responses of the soil microbiome to drought, in parallel to plant physiological changes related to water limitation. State-of-the-art isotopic labeling techniques will be used to trace alterations in the carbon and nitrogen transfer in the plant-soil microbe continuum due to drought under controlled conditions. Radiocarbon (14C) measurements of soil organic matter in mature forest stands will provide fundamental insights on the cascading effects of drought on the stability of the large pool of carbon stored in forest soils. The proposed research will lead to key insights on how belowground processes in forests respond to drought and will thus ultimately contribute to a better understanding of the carbon cycle-climate feedback in a changing climate.