The Carbon Cycle research group of VU University in Amsterdam participated in the EU FP7 research programme PAGE21 on vulnerability of permafrost carbon in the 21st century. With the last general assembly in Aukureyri, Iceland in October 2015, this research programme has come to an end. The focus of research activities of VU was the Kytalyk reaseach station near Chokurdagh in the Indigirka Lowlands in Northeast Yakutia. In close cooperation with the Russian Academy of Science institute IBPC in Yakutsk and Wageningen, University research on carbon cycle of and ecology of permafrost soils is done.

In 2015, the eddy covariance observations on CO2 and CH4 fluxes were continued at the station, for the first time the spring and autumn seasons were included succesfully. A new research programme in the framework of the Netherlands Earth System Science Centre funded by Dutch science funding organization NWO (‚Gravity‘ programme), was started with extensive sampling of thaw lake water and sediment. The aim of this research programme is to quantify the carbon cycle of thaw lakes.

In 2015, the Wageningen University team continued the measurements in the long-term Betula nana shrub removal experiment at the Kytalyk tundra research station in North-eastern Siberia. We measured surface elevations, as in 2012 (Nauta et al. 2015), to examine whether the permafrost in the removal plots had degraded further, resulting in more soil subsidence, or shows stabilisation. In addition we started a litter decomposition experiment and sampled Betula nana stems for dendrochronology. The sampling included dead and drowning shrubs from thaw ponds (Figure 1) to explore whether it is possible to see the onset of small-scale permafrost collapse, resulting in soil subsidence and increasing wetness, and how the shrubs, based on the annual ring growth pattern, responded to the increasing wetness.
The research focus at Utrecht University (Jorien Vonk) has been the effect of permafrost thaw on aquatic systems; both on land via slumping and release of organic matter from thawing permafrost into streams, lakes and rivers, but also on the continental shelf via coastal erosion and river input. Her research aim is to quantify the input, transport, and degradation pathways, as well as to qualitatively assess organic matter composition and underlying processes that drive these pathways. Ongoing research takes place in Northeast Siberia in the Kolyma River region, and the East Siberian Arctic Shelf.
As part of the work in the present Task Group, Vandenberghe particpated in a joint expedition with Hugh French and organized by a team of CAREERI, Lanzhou (prof. Huijun Jin) on the Ordos Plateau (north China) to further explore the southern boundary of permafrost extent in that region during the Last Permafrost Maximum.

Report prepared by J. van Huissteden (