Towards the first year-round continuous measurement of soil respiration at tundra warming experiment sites in Svalbard

In 2015, RIS ID 10116 entitled "Effects of summer and winter warming on CO2 efflux in high Arctic tundra" was awarded to establish in situ observations of CO2 efflux at one of the ITEX sites in Svalbard. This award created collaborations across three institutions in the topics of ongoing ITEX conducted by Dr. Ingibjorg Svala Jónsdóttir at University Centre in Svalbard, development of new techniques on continuous measurements of soil respiration by Dr. David Risk at St. Francis Xavier University in Nova Scotia, Canada, and Uni Klima in Bergen. The summer field season was extremely successful, which lead to continuous CO2 flux data collection at the ITEX site in Endahlen. The newly developed membrane-based Forced Diffusion (FD) chambers were set up at the ITEX sites in Endahlen at the sites dominated by Cassiope tetragona (x3 at each OTC within the Cassiope site and x3 near a Control plot at the same site). This site has shown a clear sign of warming effects via changes in the phenology of major vegetation present within the OTCs as a result of long-term warming of tundra ecosystem. The FD chambers are powered by a solar panel connected to a large car battery to reduce the amount of maintenance. Since its successful establishment in July of 2015, the FD chambers are taking CO2 flux measurements automatically at 4-hourly basis. The main goal of this project is to understand ecosystem C balance with summer and winter warming in Arctic tundra ecosystem by observations of ecosystem CO2 fluxes. This is a continuation of the ongoing SSF-AFG project (RIS ID 10116) aimed at resolving an annual soil respiration at a tundra warming experiment site using a new soil efflux technique to understand the effects of long-term warming of tundra on ecosystem C cycling. If awarded, this study will be the first continuous observation if soil respiration at a tundra warming experimental site in Svalbard.