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IMPRS for Global Biogeochemical Cycles PhD project Links between hydrology and carbon cycle processes within permafrost ecosystems in Northeast Siberia Supervisor: Dr. Mathias Goeckede Co-supervisors: Prof. Dr. Martin Heimann! Project description High latitude ecosystems play a pivotal role in the global carbon cycle. Approximately 50% of the global below ground carbon stocks are stored in northern permafrost soils, a pool twice as large as currently contained in the atmosphere. Future climate change threatens to destabilize these reservoirs, with the potential to trigger strong feedback processes between climate and !carbon cycle that further amplify climate change. ! This PhD project will explore in detail the links between the carbon cycle and hydrologic processes at a tundra observation site near Chersky, Northeast Siberia. In this wet tussock tundra ecosystem, water has a dominant impact on basically all ecosystem properties that influence carbon exchange processes, e.g. through altering vegetation, microbes, nutrient availability, soil thermal regime, etc. Moreover, through a drainage system the water levels at parts of this observation site have been altered for more then ten years now, so that !long-term effects of shifts in the water regime can be studied directly.! The proposed project will address the following research questions: (1) What is the amount of carbon and energy that is laterally exported through a drainage system from a permafrost ecosystem in Northeast Siberia? (2) What is the spatio-temporal variability in soil water conditions at this wet tussock tundra site, and how does it influence carbon cycle processes in a drained and undisturbed, resp., section of the observation site? In order to address these research questions, the candidate will perform summertime field campaigns at the Chersky research station in northeastern Siberia, including hydrologic experiments, and observing ecosystem exchange fluxes at small scales with soil chambers. The primary focus though will be placed on analyzing the spatio-temporal variability of the soil water conditions at high resolution, and monitoring the lateral export of water, energy and carbon through the drainage system into the nearby river. Working group & planned collaboration The proposed PhD project will be embedded within the working group ‘Integrating surface-atmosphere Exchange Processes Across Scales’, which is part of the ‘Biogeochemical Systems’ department. The work will be part of ongoing research projects focusing on permafrost carbon cycle processes in the context of high latitude climate change, including multi-agency research frameworks at both the national and international level that aim at improving our understanding of permafrost processes under a changing climate in the 21st century. coordinator: ! !Steffi Rothhardt Hans-Knöll-Str. 10 07745 Jena !Germany +49 3641 576260 www.imprs-gbgc.de www.facebook.com/imprs.gbgc [email protected] Requirements Applications to the IMPRS-gBGC are open to well-motivated and highly- qualified students from all countries. Prerequisites for this PhD project are: " a Master’s degree in hydrology, micrometeorology, geo-ecology, or related environmental or geoscientific disciplines "! experience in conducting hydrologic field and modeling experiments, and/or analyzing and interpreting lateral and vertical carbon cycle exchange processes "! good mathematical and statistical skills! "! interest in global climate change, high latitude ecology "! very good oral and written communication skills in English! (a) aerial view of the Chersky observation site, including the drainage ditch that modifies hydrologic conditions in part of the area; (b) soil chamber observation setup to monitor small-scale exchange fluxes of CO2 and CH4; (c) one of two eddy-covariance flux towers installed on the site. How to apply Application deadline for these fully funded PhD positions is September 29, 2015. Top candidates will be invited to take part in our selection symposium (December 1-2, 2015). >> Apply online: www.imprs-gbgc.de After you have been selected The IMPRS-gBGC office will happily assist you with your transition to Jena. The conditions of employment, including upgrades and duration follow the rules of the Max Planck Society for the Advancement of Science and those of the German civil service. The gross monthly income amounts about 2000 EUR, which will cover all your expenses in Germany. The Max Planck Society seeks to increase the number of women in those areas where they are underrepresented and therefore explicitly encourages women to apply. The Max Planck society is committed to increasing the number of individuals with disabilities in its workforce and therefore encourages applications from such qualified individuals. ! coordinator: !Steffi Rothhardt Hans-Knöll-Str. 10 07745 Jena !Germany +49 3641 576260 www.imprs-gbgc.de www.facebook.com/imprs.gbgc [email protected].
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