ELSIC · Ecosystem loss of soil inorganic carbon with agricultural conversion: fate, rate, mechanisms, and pathways
FP7 — People (Marie Curie Actions)
- Duration
- 2014-08-01 → 2016-07-31
- EU contribution
- €168,794
- Participants
- 1
- Scheme
- MC-IEF
Lines connect the coordinator with its partners.
Results in brief
Ecosystem loss of soil inorganic carbon with agricultural conversion: fate, rate, mechanisms, and pathways
Dr. Kim’s proposed research project was to explore how altered soil hydrology – by land use change or irrigation – can alter the dynamics of pedogenic carbonates. His proposed research followed on observations that there is an apparent loss of pedogenic carbonates in irrigated semi-arid lands. At MPI-BGC, Kim explored this process further by (1) measuring radiocarbon and stable isotope profiles of pedogenic carbonates in deep soil profiles of paired irrigated and non-irrigated lands, and (2) controlled incubation experiments designed to explore the kinetics of carbonate dissolution under conditions of different irrigation. The isotopic results demonstrated that there was no large increase in younger carbon transported downward in soil profiles in irrignated soils. The incubation experiments took a long time to set up an das a result some analyses are still underway. Hydrochemical modeling is also being perfomed, as the critical question in whether pedogenic carbonate dissolution causes a net impact on atmospheric CO2 depends on the source of Ca (weathering; i.e. new source, or reprecipitation of carbonates deeper in the same soil profile). A second project initiated by Dr. Kim was to use radiocarbon to study the age of carbon in fine roots from a number of different plantation trees. This work follows up on work we have done at MPI-BGC showing that woody roots tend to be composed of carbon up to a decade old. More data from new tree types and climate/soil regimes are useful for explaining how this can be – i.e. whether C is old because roots have long lifespans, or because roots are grown from old C in storage reserves.
Data: CORDIS, © European Union
Project objective
The goal of this proposed research is to understand effects of agricultural conversions on soil inorganic carbon (SIC) cycle. Mitigating rising atmospheric CO2 is a top priority for human and environmental health. Despite their prevalence and increasing pressure from land-use changes, effect of SIC on climate regulation is thought to be insignificant in the short-term, leading to focused efforts and research on other means of carbon sequestration. The proposed research builds on the fellow’s previous NSF-funded project, in which large losses of SIC were observed with the land-use changes, and has potential to transform the current understanding of these issues. In this proposal, soil incubations in a factorial design will simulate land use-induced ecosystem changes (soil water flux, acidification, freeze-thaw cycle) to identify mechanisms of SIC transformations. Incubators customized for the field-observed conditions such as drainage, are used to approximate water-carbonate reactions closely, and periodic measurements of inorganic carbon in gas and water fluxes using stable isotopes will determine the potential rates and pathways of fluxes from SIC. Lab and field conditions will be simulated with coupled geochemistry and hydrology codes and the results compared to those from the lab and field to help improve our understanding of SIC processes. The proposal integrates geochemistry and hydrology with original methodologies involving field, lab, and modeled data for predictive understanding of rate, fate, and mechanisms of SIC transformations with land-use changes. The mentor (Dr. S. Trumbore) and the host institute (Max Planck Institute of Biogeochemistry in Jena, Germany) collectively bring expertise in isotopes and biogeochemical modeling, demonstrate excellent research and training track records, and comprise a research setting uniquely adapted to the project and the fellow.
Original text from CORDIS.
Participants
- MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV · MUNCHENCoordinatorGermany
Links
Data: CORDIS, © European Union