Lateral carbon export has low impact on the net ecosystem carbon balance of a polygonal tundra catchment

Permafrost-affected soils contain large quantities of soil organic carbon (SOC). Changes in the SOC pool of a particular ecosystem can be related to its net ecosystem carbon balance (NECB) in which the balance of carbon (C) influxes and effluxes is expressed. For polygonal tundra landscapes, accounts of ecosystem carbon balances in the literature are often solely based on estimates of vertical carbon fluxes. To fill this gap, we present data regarding the lateral export rates of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) from a polygonal tundra site in the north Siberian Lena River delta, Russia. We use water discharge observations in combination with concentration measurements of waterborne carbon to derive the lateral carbon fluxes from one growing season (2 June-8 September 2014 for DOC, 8 June-8 September 2014 for DIC). To put the lateral C fluxes into context, we furthermore present the surface-atmosphere eddy covariance fluxes of carbon dioxide (CO.sub.2) and methane (CH.sub.4) from this study site.