Nonlinearities and Alternative States of Biogeochemical Cycling in Terrestrial Ecosystems

• Applicant: Dr. Carlos A. Sierra
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2014 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 257784447

Terrestrial ecosystems play a very important role in the global Carbon cycle; they exchange carbon dioxide with the atmosphere and store it in ecosystem pools for a period of time. Although a considerable amount of research has been conducted to study the magnitude of carbon storage, uptake and release in terrestrial ecosystems, less attention has been given to the amount of time carbon is stored in these systems. A quantification of the timescales of carbon storage in the terrestrial biosphere is important because it helps to quantify this ecosystem service over an explicit period of time as well as potential benefits or consequences of ecosystem management. To build on the previous work of the Emmy-Noether project 'Nonlinearities and alternative states of biogeochemical cycling in terrestrial ecosystems', an analysis of the timescales of carbon storage in the terrestrial biosphere is proposed; calculating the age and transit time distributions of carbon for a number of terrestrial biosphere models. One main objective is to quantify the amount of time carbon Atoms spend in the terrestrial biosphere. A second objective is to propose an index to quantify the radiative forcing effects of carbon storage in ecosystems. This metric is similar to the widely-known Global Warming Potential, but instead of using the age distribution of Carbon in the atmosphere, we use the transit time distribution of carbon in the terrestrial biosphere to quantify avoided radiative forcing due to ecosystem carbon storage. The main value of the project will be that it will provide results on the duration of C sequestration in terrestrial ecosystems, which is crucial for evaluating climate protection measures.

• DFG Programme: Independent Junior Research Groups