%0 Journal Article
%T Spectral Estimation of Soil Properties in Siberian Tundra Soils and Relations with Plant Species Composition
%A Harm Bartholomeus
%A Gabriela Schaepman-Strub
%A Daan Blok
%A Roman Sofronov
%A Sergey Udaltsov
%J Applied and Environmental Soil Science
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/241535
%X Predicted global warming will be most pronounced in the Arctic and will severely affect permafrost environments. Due to its large spatial extent and large stocks of soil organic carbon, changes to organic matter decomposition rates and associated carbon fluxes in Arctic permafrost soils will significantly impact the global carbon cycle. We explore the potential of soil spectroscopy to estimate soil carbon properties and investigate the relation between soil properties and vegetation composition. Soil samples are collected in Siberia, and vegetation descriptions are made at each sample point. First, laboratory-determined soil properties are related to the spectral reflectance of wet and dried samples using partial least squares regression (PLSR) and stepwise multiple linear regression (SMLR). SMLR, using selected wavelengths related with C and N, yields high calibration accuracies for C and N. PLSR yields a good prediction model for K and a moderate model for pH. Using these models, soil properties are determined for a larger number of samples, and soil properties are related to plant species composition. This analysis shows that variation of soil properties is large within vegetation classes, but vegetation composition can be used for qualitative estimation of soil properties. 1. Introduction The Arctic is experiencing the highest rates of warming compared with other world regions [1] that will likely have great impacts on high-latitude ecosystems [2, 3]. The large and potentially volatile carbon pools stored in Arctic soils have the potential for large emissions of greenhouse gases in the form of both CO2 and CH4 under warmer and potentially drier conditions, resulting in a positive feedback to global warming [4]. Further, climatic changes may impact vegetation development and affect water and energy exchange in tundra ecosystems, with consequences for permafrost thaw depth [5, 6] and concomitant soil carbon release to the atmosphere [7¨C9]. The response of soil organic matter decomposition to increasing temperature is a critical aspect of ecosystem responses to global change [10]. It has been suggested that a warmer and drier climate in Arctic regions might increase the decomposition rate and, hence, release more CO2 to the atmosphere than at present [11, 12]. Besides expected changes within the soil itself, changes on the vegetation development are observed and expected for future warming. Plant species composition may greatly affect rates of soil processes, including decomposition [13]. In general, species within a growth form (graminoids, evergreen
%U http://www.hindawi.com/journals/aess/2012/241535/