Molecules in a Living Landscape: Soil Carbon Storage and Vegetation in a Greenland Mosaic
Arctic soils hold an estimated 1672 petagrams of carbon—that is more than 2 times the amount of carbon in the atmosphere. Temperature is a main control of biological soil respiration, so a warming Arctic climate will release soil organic into the atmosphere. Contemporary models use biochemical principles to predict soil carbon response to temperature, but these predictions often differ from direct observations because they fail to represent ecosystem variables that affect the nature of soil organic matter and the subsurface environment. This study examines soil carbon storage across an Arctic tundra landscape that is variable with respect to vegetation type, soil characteristics, landscape position. We analyzed satellite imagery to characterize the variation of vegetation types and to select representative sites for plant community observation, soil sample collection and soil respiration measurements. With remote sensing and intense field observation, this study links local scale properties to landscape level dynamics to understand spatial variability of carbon storage and the implications for processes and dynamics at the landscape scale. A long-term goal of this research is to develop a spatially explicit model of soil organic matter, soil respiration and temperature sensitivity of soil carbon dynamics for western Greenland tundra ecosystems.