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Complex river rehabilitation/restoration projects devote equal attention to the improvement of hydromorphological conditions and the neighbouring floodplain environment. Since land use exerts a heavy control on the hydrological cycle of floodplains, land use optimization is a central task in floodplain rehabilitation. In floodplains where large surfaces are temporarily inundated, the optimal allocation of land use classes involves the preservation of wetlands, maintenance of grasslands (meadows and pastures) and forests, and the restriction of arable land to higher ground with the lowest inundation hazard. The detailed mapping of land use against the distribution of soil types and fluvial landforms provides a solid basis for land use optimization. Rehabilitation design is presented in the paper on the example of the Kapos Valley, where inundations in the wet year of 2010 caused great damage to agricultural crops and efforts are directed to better water management (excess water reduction and floodwater retention) on the floodplain. Land use conversions, which are less expensive and easier to implement, are preferred to structural (engineering) solutions.

The identification of drought-sensitive areas (DSAs) in floodplain Fluvisols of high textural pedodiversity is crucial for sustainable land management purposes. During extended drought periods moisture replenishment is only available by capillary rise from the groundwater. However, moisture flux is often hindered by capillary barriers in the interface between layers of contrasting textures. The results of HYDRUS-1D simulations run on multilayered soil profiles were integrated into textural maps to determine the spatial distribution of water dynamics on the floodplain of the Drava River (SW Hungary). Model runs and field data revealed limited moisture replenishment by capillary rise when both contrasting textural interfaces and sandy layers are present in the profile. By implementing these textural and hydraulic relations, a drought vulnerability map (DSA map) of the operational area of the Old Drava Programme (ODP) was developed. According to the spatial distribution of soils of reduced capillary rise, 52% of the ODP area is likely threatened by droughts. Our model results are adaptable for optimisation of land- and water-management practices along the floodplains of low-energy and medium-sized rivers under humid continental and maritime climates.

Constructions of dams influence river courses by cutting off sediment delivery and altering flow regime. We conducted flume experiments to study how sediment starvation, flow deficit and occurrence of series of floods with sediment load influence the evolution of channel planform. Results indicated that reduced flow caused a transition from a braided to incised single-thread planform with remains of inactive channels. The planform resembled rivers suffering from flow reduction caused by dams and constructions of irrigation canals (e.g., Central Platte River, USA). Simulation of series of floods with no sediment delivery caused the formation of an anabranching planform with incised main channel, alluvial islands, and side channels active at high flows. This evolution corresponds to river courses altered by sediment starvation and series of floods (e.g., the lower Drava River, Hungary). Floods with delivery of fines created a single-thread, incised channel with terraces along banks. Such channels are formed by rivers closed by dams, and compensating sediment deficit by sediment load from tributaries and/or floodplains (e.g., the Green River, USA). The flume tests demonstrated how flow and sediment deficit influence river channels and that the potential for restoration strongly depends on possibilities for the activation of sediment supply. However, restoration of pre-dam conditions is often impossible owing to other hydro technical works and land use changes. The highest restoration potential refers to the rivers compensating sediment delivery blocked by dams with tributary and floodplain resources.

The hydromorphological properties of rivers and their floodplains receive increased attention both in basic research and water management. A comparison of hydromorphological parameters before and after river regulation (involving floodplain drainage) provides important information for river management, particularly floodplain rehabilitation. The paper assesses a selected reach of the Drava River and the corresponding floodplain utilising two international approaches, the REFORM framework and the Italian Morphological Quality Index.

Landscape memory and ecological memory are relatively new concepts developed independently in geomorphology and ecology. Eco-geomorphology strives to enrich the concept of landscape memory with that of ecological memory, as ecosystems build inherent parts of landscapes and are controlled by geomorphological factors. This integration is illustrated by a small-scale eco-geomorphological case study of links between ecosystems and their hydrogeomorphological template, in the floodplain of a medium size Hungarian River. Despite that the river is channelized by 1835 and most of the study area is under intensive agricultural cultivation, the seminatural vegetation along the various reaches shows significant variations according to geomorphological background variables: detrended correspondence analysis yields results of p = 0.002 significance. Our results prove that geomorphological patterns in floodplains, defined by landscape memory, and the related vegetation patterns, as manifestations of ecological memory, jointly determine the face of floodplain landscapes. The integration of ecological memory into the definition of landscape memory may help meet the challenges of eco-geomorphology and facilitate a holistic understanding of landscapes, and thus be instrumental for reconstructing past environments—both in theory (scientific research) and practice (rehabilitation projects). Copyright © 2013 John Wiley & Sons, Ltd.

Floodway delineation, zoning and hydrodynamic modelling for a section of the Drava River was carried out with MIKE 21 software at a one-time input flood pulse of 3000 m3s-1 discharge. The objective of the current study was the delineation and mapping of floodway zones in the form of a set of georeferenced GIS data for the section between Őrtilos (river kilometer 236 km) and Drávaszabolcs (70.2 km). Zonation was based on water velocities. Four zones were delineated upstream Barcs, and three between Barcs and Drávaszabolcs, where, due to the confined floodplain downstream Barcs, no stagnant water area was identified. Specific velocities ranged between 0.089 and 3.476 m2s-1 and 0.075 and 2.01 m2s-1 upstream and downstream Barcs, respectively, markedly lower than stated in the Government Decree (0.2 to 6.0 m2s-1). The primary and secondary conveyance zones covered a combined area of about 40% of the entire floodplain, while the remaining 60% included both the transitional and stagnant water zones upstream Barcs and solely the transitional zone downstream Barcs. Our analyses help to mitigate the effects of flood peaks and provide information for decision makers and local stakeholders on flood management tasks.

A sufficiently detailed floodplain typology is assumed to be useful in the estimation of local flood risk, planning flood control and river restoration measures and for the survey of landscape ecological patterns. Although floodplains are defined by a range of hydrological, geomorphological and geoecological criteria, floodplain classification should start with geomorphometric characterization of stream channels and floodplains in a valley setting. The study areas selected for the geomorphometric analyses are two representative catchments in the hill regions of Southwest-Hungary: the Kapos River, a river of medium size by Hungarian standards (a tributary of the Sio Canal and of the Danube), and a small tributary in the Drava River system, the Bukkosd Stream. For the delimitation and characterization of their floodplains Digital Elevation Models (DEMs), archive military surveys, and topographic maps have been used. The diagnostic parameters selected for the classification are floodplain width, floodplain (or valley floor) slope, valley confinement (expressed by a longitudinal profile index, LPI), channel sinuosity (indicating river mechanism), and valley depth. They have been analyzed in relationship with the distribution of tributary confluences along the river longitudinal profile. Currently, a large majority of watercourses in the region are channelized and some are dammed for fish-ponds, but the present-day floodplains had been built earlier by seminatural streams. Therefore, the classification is based on pre-regulation floodplain conditions (reconstructed from archive sources), which should be target conditions for any future management or restoration efforts. A visual comparison of the distribution of floodplain parameter values along the longitudinal profile shows that the LPI index is a useful tool for the characterization of the floodplain segments. The floodplain types are classified as 1) no floodplain (LPI values are > 0.25, mostly > 0.5); 2) gradually broadening floodplain (LPI is between 0.1 and 0.25); 3) partially confined floodplain (LPI ranging between 0.05 and 0.1) and 4) mostly unconfined floodplain with bottleneck reaches (LPI fluctuating more widely, from 0.05 to 0.25).

Neotectonic movements often result in marked large-scale asymmetry of river valleys. The characteristically rectangular (“chequerboard”) drainage pattern of Southern Trandanubia has provoked discussions among Hungarian geologists and geomorphologists for more than a century. In the centre of this area is the Kapos River valley, the asymmetry of which is obvious to any visitor. Although this asymmetry has been undoubtedly controlled by neotectonic movements to a large extent, it is probably also enhanced by geomorphic processes. The degree and distribution of asymmetry is quantified using different morphometric indices calculated from a Digital Elevation Model. An overview of the tectonic models proposed to identify the reasons behind asymmetry in the study area is also presented. It is pointed out that the asymmetry is associated with the alignment of two tectonic lines crossing the catchment and also manifested in the planform of the valley floor (i.e. in the shape of the morphological floodplain).

The 15–18 May 2010 flood events on the watershed of the Bukkosd Stream, SW Hungary, are described, their general topographic and hydrologic characteristics are analyzed using the HEC-HMS numeric runoff model, and geomorphological impacts are surveyed. In addition to extreme rainfall volumes, the major reasons found to contribute to extreme impoundment were the fluctuating and locally reduced width of the valley, the confluence of tributaries, which create intermittent bottlenecks for drainage, and high soil moisture contents, which also caused slope instability in deeper soil mantle. Flash flood hazard is closely associated with landslide hazard in upland valleys.