Boreal permafrost soils store large amounts of organic carbon (OC). Parts of this carbon (C) might be black carbon (BC) generated during vegetation fires. Rising temperature and permafrost degradation is expected to have different consequences for OC and BC, because BC is considered to be a refractory subfraction of soil organic matter. To get some insight into stocks, variability, and characteristics of BC in permafrost soils, we estimated the benzene polycarboxylic acid (BPCA) method-specific composition and storage of BC, i.e. BPCA-BC, in a 0.44 km(2)-sized catchment at the forest tundra ecotone in northern Siberia. Furthermore, we assessed the BPCA-BC export with the stream draining the catchment. The catchment is composed of various landscape units with south-southwest (SSW) exposed mineral soils characterized by thick active layer or lacking permafrost, north-northeast (NNE) faced mineral soils with thin active layer, and permafrost-affected raised bogs in plateau positions showing in part thermokarst formation. There were indications of vegetation fires at all landscape units. BC was ubiquitous in the catchment soils and BPCA-BC amounted to 0.6-3.0% of OC. This corresponded to a BC storage of 22-3440 g m(-2). The relative contribution of BPCA-BC to OC, as well as the absolute stocks of BPCA-BC were largest in the intact bogs with a shallow active layer followed by mineral soils of the NNE aspects. In both landscape units, a large proportion of BPCA-BC was stored within the permafrost. In contrast, mineral soils with thick active layer or lacking permafrost and organic soils subjected to thermokarst formation stored less BPCA-BC. Permafrost is, hence, not only a crucial factor in the storage of OC but also of BC. In the stream water BPCA-BC amounted on an average to 3.9% of OC, and a yearly export of 0.10 g BPCA-BC m(-2) was calculated, most of it occurring during the period of snow melt with dominance of surface flow. This suggests that BC mobility in dissolved and colloidal phase is an important pathway of BC export from the catchment. Such a transport mechanism may explain the high BC concentrations found in sediments of the Arctic Ocean. [References: 72

Soils of the high latitudes are expected to respond sensitively to climate change, but still little is known about carbon and nitrogen variability in them. We investigated the 0.44-km(2) Little Grawijka Creek catchment of the forest tundra ecotone (northern Krasnoyarsk Krai, Russian Federation) in order (i) to relate the active-layer thickness to controlling environmental factors, (ii) to quantify soil organic carbon (SOC) and total nitrogen (NT) stocks, and (iii) to assess their variability with respect to different landscape units. The catchment was mapped on a 50 x 50 m grid for topography, dominant tree and ground vegetation, organic-layer and moss-layer thickness, and active-layer thickness. At each grid point, bulk density, and SOC and NT concentrations were determined for depth increments. At three selected plots, 2-m deep soil cores were taken and analysed for SOC, NT and C-14. A shallow active layer was found in intact raised bogs at plateaux situations and in mineral soils of north-northeast (NNE) aspect. Good drainage and greater solar insolation on the south-southwest (SSW) slopes are reflected in deeper active layers or lack of permafrost. Organic carbon stocks to a soil depth of 90 cm varied between 5 and 95 kg m(-2). The greatest stocks were found in the intact raised bogs and on the NNE slopes. Canonical correspondence analysis indicates the dominant role of active-layer thickness for SOC and NT storage. The 2-m soil cores suggest that permafrost soils store about the same amount of SOC from 90 to 200 cm as in the upper 90 cm. Most of this deep SOC pool was formed in the mid-Holocene (organic soils) and the late Pleistocene (mineral soils). Our results showed that even within a small catchment of the forest tundra, active-layer thickness and, hence, SOC and NT storage vary greatly within the landscape mosaic. This has to be taken into account when using upscaling methods such as remote sensing for assessing SOC and NT storage and cycling at a regional to continental level. [References: 44

Zyklische, handnahe Inspektionen nach DIN 1076 bilden die Datenbasis für die Instandhaltungsplanung unserer Ingenieurbauwerke, die Berechnung von Zustandsnoten erfolgt dabei auf Grundlage erkannter Schäden. Die Dokumentation der Prüfung erfolgt überwiegend im Programmsystem SIB‐BW. Das System sorgt für einen vergleichsweise einheitlichen Bewertungsstandard und ermöglicht in begrenztem Umfang retrospektive und prospektive Betrachtungen für die Instandhaltungsplanung. Neuere Entwicklungen wie BIM oder die in anderen Wirtschaftszweigen etablierte kontinuierliche, sensorbasierte Zustandserfassung bleiben bislang konzeptionell unberücksichtigt. Vor dem Hintergrund der digitalen Transformation stellt sich die Frage, wie sich die etablierte manuelle und die digitale Zustandsbeurteilung sowie BIM‐generierte Daten in eine durchgängige digitale Prozesskette integrieren lassen und welcher Nutzen sich so generieren lässt. Die Hamburg Port Authority (HPA) hat daher das Projekt „smartBridge Hamburg“ initiiert, das prototypisch, anhand der Köhlbrandbrücke in Hamburg das Konzept des digitalen Zwillings pilotiert. Der digitale Zwilling dient dazu, BI‐Modell sowie analoge und elektronische Zustandserfassung konzeptionell zu vereinigen und die über mehrere Schichten aggregierten Daten unterschiedlichsten Nutzergruppen bedarfsgerecht bereitzustellen. Der Beitrag stellt Prämissen und Grundüberlegungen zur Projektinitiierung vor.