We compared synchrotron-based C near-edge X-ray absorption fine structure (NEXAFS) and CPMAS C nuclear magnetic resonance (NMR) spectroscopy with respect to their precision and accuracy to quantify different organic carbon (OC) species in defined mixtures of soil organic matter source compounds. We also used both methods to quantify different OC species in organic surface horizons of a Histic Leptosol as well as in mineral topsoil and subsoil horizons of two soils with different parent material, stage of pedogenesis, and OC content (Cambisol: 15-30 OC mgg, Podzol: 0.9-7 OC mgg). CPMAS C NMR spectroscopy was more accurate and precise (mean recovery of different C functional groups 96-103%) than C NEXAFS spectroscopy (mean recovery 92-113%). For organic surface and topsoil samples, NMR spectroscopy consistently yielded larger O-alkyl C percentages and smaller alkyl C percentages than C NEXAFS spectroscopy. For the Cambisol subsoil samples both methods performed well and showed similar C speciation results. NEXAFS spectroscopy yielded excellent spectra with a high signal-to-noise ratio also for OC-poor Podzol subsoil samples, whereas this was not the case for CPMASC NMR spectroscopy even after sample treatment with HF. Our results confirm the analytical power of CPMAS C NMR spectroscopy for a reliable quantitative OC speciation in soils with>10mgOCg. Moreover, they highlight the potential of synchrotron-based C NEXAFS spectroscopy as fast, non-invasive method to semi-quantify different C functional groups in soils with low C content (0.9-10mgg).

Since the end of the Little Ice Age (LIA), formerly glaciated areas have undergone considerable changes in their morphodynamics due to external forces and system-internal dynamics. Using multi-temporal high-resolution digital elevation models (DEMs) from different remote sensing techniques such as historical digital aerial images and light detection and ranging (LiDAR), and the resulting DEMs of difference (DoD), spatial erosion and accumulation patterns can be analyzed in proglacial areas over several decades. In this study, several morphological sediment budgets of different test sites on lateral moraines and different long-term periods were determined, covering a total period of 49 years. The test sites show high ongoing morphodynamics, and therefore low vegetation development. A decrease as well as an increase of the mean annual erosion volume could be demonstrated at the different test sites. All test sites show a slope–channel coupling and a decrease in the efficiency of sediment transport from slopes to channels. These developments are generally subject to conditions of increasing temperature, decreasing short-term precipitation patterns and increasing runoff from adjacent mountain streams. Finally, the study shows that sediment is still available on the investigated test sites and the paraglacial adjustment process is still in progress even after several decades of deglaciation (~133 years).

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<p>Glacier forelands are perfect for analysing the development of plant communities from zero onward. According to Matthews (1992), the chronosequence can act as a spatial representation of the temporal sequence. Therefore, it is ideal to analyse changes in landscape and land cover in time slices. Development of plant communities does not only depend on the age of the deposits, but also on topography, microclimate, soil development, and geomorphological processes as well as on biotic interactions. In the long term, permanent plots represent an adequate method to follow the colonisation on differently aged terrain throughout time.</p><p>The main research question of the study is: Do cryospheric changes influence plant community development in time and space? During the first study year we were focused on the following questions: i) How fast does a plant community evolve? ii) How many species do occur on different moraine stages? iii) How do soil parameters correlate with primary succession stages?</p><p>The study site is located in the southern part of the Central European Alps, Martell Valley (South Tyrol, Italy). We established 12 permanent plot clusters of 2 x 5 m on areas deglaciated between 1985 and 2018, two per retreat area. In each square meter of these clusters, species composition, cover, and number of individuals were sampled. On the ground moraines of the glacier stages 1911 and approximately 1850 we recorded species composition and cover on 10 x 10 m plots (four plots in total). In all plot clusters and plots on the old moraines, soil temperature and soil water potential as well as relevant soil parameters were measured.</p><p>We found up to two vascular plant species per square meter on areas ice free for one year and up to 16 vascular plant species per square meter on areas ice free since 1985.</p><p>On the moraines of 1911 were up to 39 vascular plant species per plot with a mean cover of 52.5 %. On the moraines of 1850 we found up to 43 vascular plant species with a mean cover of 40 %.</p><p>In the next step we will analyse the effects of pioneer, early and late successional species on morphodynamic processes and their response to these processes using functional traits.</p><p>Matthews, J.A. (1992): The ecology of recently-deglaciated terrain: a geoecological approach to glacier forelands and primary succession. Cambridge University Press, Cambridge.</p>