Abstracts Database
Return to Search Results Return to Original Search Page

Register Number: ER65430
Title: Can Microbial Ecology and Mycorrhizal Functioning Inform Climate Change Models?
Principal Investigator: Hofmockel, Kirsten
Institution Address: Ames, IA 50011-2207
Awarded Amount to Date and B&R Code :
FY 2015$0 k
FY 2014$0 k
FY 2013$276 kKP170201
FY 2012$200 kKP170201
DOE Program Manager: Daniel Stover
BER Division: Climate and Environmental Sciences
Research Area: Terrestrial Ecosystem Science
Abstract Submit Date: 10/09/2013
Project Term: 08/01/2012 - 07/31/2015
Abstract: Feedbacks between forest ecosystems and global climate are regulated in part by the coupled cycling of carbon and nitrogen throughout the atmosphere-plant-soil continuum. However, the current generation of models that link the terrestrial carbon cycle to climate neglect many fundamental plant-microbe interactions that regulate this coupling. One critical link in coupled carbon-nitrogen cycling is the role of organic nitrogen in providing plant nutrition and in contributing to forest carbon storage. This research will investigate the consequences for ecosystem carbon cycling in climate change experiments of microbial decomposition of organic nitrogen and its subsequent uptake by mycorrhizal (plant associated) fungi. Using archived samples and data from the Duke Forest and Oak Ridge National Laboratory Free Air CO2 Enrichment (FACE) experiments, we will use stable isotope methods to estimate the source and quantify the use of organic nitrogen in different mycorrhizal taxa. Using fresh samples from the Spruce and Peatland Responses Under Climatic and Environmental Change (SPRUCE) experiment we will trace carbon from the atmosphere through plants and into the microbial community. Data generated from the three field experiments will be used in conjunction with the newly developed MySCaN (Mycorrhizal Status, Carbon and Nutrient cycling) model to explore how organic nitrogen uptake by mycorrhizal fungi affects forest carbon cycling under different climate scenarios. The model explicitly incorporates organic nitrogen movement and key microbial components to predict organic nitrogen changes and soil carbon storage. These measurements and modeling will inform global biogeochemical models by providing new insights into how carbon and nitrogen cycling are linked to plant and microbial dynamics in forest systems. This work will accordingly be useful in efforts to incorporate key processes (such as nitrogen constraints to plant growth and soil carbon storage) into the carbon dynamics of large-scale models used to predict forest-climate feedbacks.