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Understanding the relationship and spatial distribution of multiple ecosystem services (ES) in the context of underlying socio-environmental conditions is an essential element of national ecosystem assessments. Here, we use Germany as an example to present a reproducible blueprint approach for mapping and analysing ecosystem service bundles (ESB) and associated socio-environmental gradients. We synthesized spatial indicators of eleven provisioning, regulating and cultural ES in Germany and used the method of self-organizing maps (SOM) to define and map ESBs. Likewise, we collated data from 18 covariates to delineate socio-environmental clusters (SEC). Finally, we used an overlap analysis to characterise the relationship between the spatial configuration of ESBs and co-occurring SECs. We identified and mapped eight types of ESBs that were characterized to varying degrees by provisioning, cultural and regulating/maintenance services. While ESBs dominated by provisioning ES were linked to regions with distinct environmental characteristics, cultural ESBs were associated with areas where environmental and socio-economic gradients had similar importance. Furthermore, spatial stratification of ESBs indicated hot spots where more detailed analysis is needed within national assessments. Our approach can serve as a blueprint for ESB analysis that can be reproduced in other geographical and environmental settings.

Natural levees can be observed worldwide in nearly all river systems characterized by frequent flooding in combination with the transport of suspended bed material. Several parameters and processes have been suggested to explain the formation and the highly variable geometry of natural levees. However, the effect of bedforms migrating in the main-channel has not been amongst the studied parameters and processes. To fill this gap, this study investigates the relationship between bedforms and natural levee formation by flume experiments. Experiments were conducted in a 2 m wide and 30 m long sediment recirculating flume, monitoring the bed level elevation in the main channel by ultrasonic sensors as well as recording the levee development on the floodplain by a camera. The effect of different bed configurations on the developed levees is compared, and discussed, showing that bedforms could enhance levee formation.

In recent ecosystem service studies, historical data have gained importance as basis for analysing temporal trends and for adapted land management strategies; however, the total number of such studies remains small. Contributing to recent efforts, the primary objective of this study was to assess local ecosystem service products historically used in Germany and to link their distribution patterns to environmental gradients and traditional land-use systems. From maps and detailed regional descriptions of regionally distinct historic farmsteads, building materials used and village types we extracted information on ecosystem service products appropriated in 1950 and before. A spatial model was used to test the derived ecosystem service diversity against topo-climatic conditions. Regional service richness was further compared to the type of traditional land-use system (i.e. focus on crops, focus on livestock or mixed systems). We were able to identify hot spots of historical ecosystem service provisioning in Northern and Southern Germany, whereas significantly lower service numbers were recorded in Eastern Germany. The strong spatial differences in the diversity of historical service products could be explained best by (high) precipitation during the vegetation period. Furthermore, traditional livestock keeping, which relied on various fodder sources and fertilisation techniques to improve poor soil quality, and mixed systems mostly co-occurred with higher regional ecosystem service richness. The baseline of historical ecosystem service provisioning analysed here aids our understanding of current land-use patterns in Germany. Furthermore, a change of perception for specific landscape elements became apparent from our analyses. For example, hedges planted to separate livestock and to provide fuel in the past are today appreciated as important elements for biodiversity conservation. Furthermore, our study helps to preserve knowledge about locally sourced ecosystem services thereby increasing the understanding of cultural landscapes which may help to maintain their remnants.

Sub-Saharan Africa has experienced substantial urbanisation and land degradation processes over the past three decades. Using multi-source satellite imagery combined with geographical and demographic data, this study's aims were to analyse the extent of land cover changes (LCC) and identifying major landscape transformation processes (LTP) and their drivers for four West African cities in Mali, Burkina-Faso, Nigeria and Niger. A common classification scheme was used for a visual interpretation of Corona images from the 1960s and an automated classification of Landsat scenes from 1986, 2000/2001 and 2009. Based on a postclassification comparison LCC were summarized and related to the demographic trends of the past 50 years. Map changes were calculated from 1986 to 2009 to depict LTP (urbanisation, crop expansion, deforestation, and land abandonment) for the cities and their respective hinterlands. To investigate the effect of accessibility and infrastructural factors, LTP were related to the distance to roads, surface water and urban areas. From 1960 to 2009 a large-scale urban agglomeration was detected and the proportion of cultivated land in former natural woody savannas surrounding all four cities increased by 35%. The expansion of cropland during the past 30 years seemed to depend greatly on the availability of irrigation water in the semi-arid Sahelian cities (Kano and Niamey), whilst this was not a major driving factor for the cities of the Sudanian zone (Sikasso and Bobo-Dioulasso). Given the likely increase in water scarcity and land suitable for agriculture, ex ante land use planning and monitoring strategies will become increasingly important.

Flow in rivers and on floodplains is complex as it is affected by several interconnected factors such as topography, sediment transport and vegetation characteristics. The resulting processes are explained by the measure “Hartheim” planned for retention purposes at the Upper Rhine river. On the basis of existing formulas and instruments it is demonstrated that a good estimation of the development of the measure is possible. The proposed procedure is a useful tool for estimating morphological developments of restored river sections.

A 1D steady-state flow simulation model was developed. A module evaluating the roughness parameters due to the surface roughness of the main channel and floodplains, riparian forests on the floodplains, and the momentum exchange between the main channel and floodplains was introduced into the model. In the module, the roughness parameters were evaluated by the formulas proposed by the DVWK [Hydraulische Methoden zur Erfassung von Rauheiten (1990); Hydraulische Berechnung von Fliesgewassern (1991)] for steady and uniform flow conditions. The model was calibrated with data obtained from three flood events. Roughness parameters of the main channel and floodplains of both sides were identified in the situation before May 1999. The morphological situation changed slightly. Several sensitivity analyses were carried out for the following cases: (a) the morphological situation before May 1999 with the original parameters, (b) the situation of (a) with various parameters to the realistic extent, (c) the situation being so that the floodplain on the German side were imaginarily enlarged up to utmost 90 m with the original vegetation, and (d) the situation of (c) with various parameters to the realistic extent. Many combinations of the roughness parameters due to the bed roughness and density of the vegetation were examined. The results showed that the most significant parameter is the bed roughness of the floodplains, and the next is that of the main channel. A modification of parameters of the riparian vegetation is of minor importance. The model was extended to a 1D unsteady state flow simulation model and applied to two flood data obtained in the reach between Rheinweiler (186.156 km from Lake Constance) and Hartheim (214.244 km) in Germany in 1998 and 1999. Both measured and calculated hydrographs at Hartheim had their peak discharge at the same time, and the discrepancy of the discharge between the measured and calculated hydrographs was less than 10%.

The paper reports on the methodology applied to assess the morphodynamical development of a river reach which is planned to be re-dynamised, according to the “INTERREG IVa - Redynamisation of the Old Rhine” project (2009-2012). The river reach is located at the Upper Rhine parallel to the Grand Canal d’Alsace. Most of the discharge is directed through the canal and only a minimum discharge is flowing through the River Rhine. In the ca. 40 km long section morphological features are nowadays absent due to limited sediment supply and transport. A dynamic river bed shall be supported by means of floodplain lowering, sediment deposition and removement of bank protection. The applied methodology combines 3D-numerical modelling of the flow field and stability approaches to assess morphological changes with particular reference to the sediment dynamics and stability of the main channel and the floodplain areas.