Student Opportunity Announcements

PhD position aquatic biogeochemistry in tundra streams


PhD position in Physical geography directed towards studies of carbon
in tundra streams

The Department of Ecology and
Environmental Science
(EMG) at Umeå University conducts research and offers
postgraduate studies in Ecology, Environmental Sciences and Physical
Geography. The department of EMG has about 160 members, including
approximately 50 PhD-students (for further information, see The Climate Impacts Research Centre
is part of EMG and undertakes research in how climate and
environmental changes affect the ecosystems of the arctic. Most of the
staff at CIRC is stationed year-round in Abisko, in Kiruna municipality
(for further information, see The
PhD position will be affiliated to CIRC and all fieldwork will be conducted
in the Abisko area.

The invisible stream carbon-an early indicator of ecosystem change-Streams
are sensitive sentinels for environmental change by their integration of
processes in terrestrial and aquatic systems. Upland headwater streams in
the north Swedish tundra show seasonally exceptional high concentrations of
uncolored dissolved organic carbon (DOC) and CO2. We suggest that this
reflects on-going changes in the terrestrial environment responding in
their delivery of carbon (C) to the recipient aquatic systems. This is a
hitherto less well described process of a changing tundra landscape that
will have large implications for the positive feedback on the global
climate warming because of the large quantities of C that is stored in
tundra soils. In this PhD you will 1) disentangle the origin and causes
behind the stream C observed in tundra streams, 2) determine the importance
of old buried C for the formation of CO2 and DOC 3) determine how it
relates to landscape features such as proxies for cryogenic activity,
permafrost and, vegetation. The successful PhD candidate will use
quantitative and qualitative approaches to study stream CO2 and DOC
dynamics that includes the use of stable isotope techniques in streams and
soils. The main focus will be on the aquatic systems but will also include
some work in the terrestrial environment. The field- and laboratory work
will be performed mostly in the subarctic tundra near Abisko (north
Sweden), at the research facilities of CIRC, and at EMG in Umeå.
Supervisors will be Prof. Reiner Giesler, Dr. Ann-Kristin Bergström and Dr.
Ryan Sponseller (CIRC, Umeå University). The expected starting date is 1
May 2014 but this can be negotiated. More detailed information about the
position can be found here.