ESTIMATION OF SOIL ORGANIC CARBON STOCK IN THE GLACIER FORELAND OF MIDTRE LOVENBREEN, IN THE HIGH ARCTIC

Abstract

Global warming leads to rapid melting of glaciers in the high Arctic, exposing new soil surfaces. Soil organic carbon (SOC) accumulation in the proglacial environment has initiated along soil chronosequence after microorganisms and plants have settled down. The quantity and rate of SOC accumulation are also affected by several environmental factors which need to be identified and more throughout studied, however, these influences have not yet been investigated considerably. Hence, we are aiming to estimate the SOC stock in the glacier foreland of the Midtre Lovenbreen, Spitsbergen, Norway (79°N, 12°W) by considering the deglaciated years and several environmental factors such as microtopography, runoff activity, etc. A total of 36 sampling points were selected to collect soil for 0-30 cm depth, and vegetation was surveyed from 93 points. The SOC stock was estimated from the quantity of SOC and bulk density calculated from soil texture. A Multiple Correspondence Factorial Analysis (MCFA) was conducted to investigate the relationship between vegetation and SOC content. The results of MCFA were hierarchically classified with Ward criteria to cluster the sampling points. Since each class is defined by the frequencies of the modalities of variables, Bayesian conditional probabilities for each pixel were calculated by using environmental variables acquired from remote sensing imagery and DEM. The highest probability class was assigned to produce of a map of SOC and to estimate SOC stock in the glacier moraine. This study would contribute to understand the initial soil development in the high Arctic ecosystem with a consideration of environmental parameters as well as soil age