The state of river channels and their riparian zones in terms of geomorphology and vegetation has a significant effect on water and sediment transport in headwater catchments. High roughness in natural rivers due to vegetation and geomorphological attributes generate drag on flowing water. This drag will slow water discharge, which in turn influences the sediment dynamics of the flow. The impacts of changes in the management of rivers and their riparian zone (either by catchment managers or river restoration plans) impacts both up-as well as downstream reaches, and should be assessed holistically prior to the implementation of these plans.To assess the river's current state as well as any possible changes in geomorphology and vegetation in and around the river, effective approaches to characterise the river are needed. In this paper, we present a practical approach for making detailed surveys of relevant river attributes. This methodology has the benefit of being both detailed -describing river depth, width, channel morphology, erosive features and vegetation typesbut also being practical in terms of time management. This is accomplished by identifying and describing characteristic benchmark reaches (typical sites) in detail against which the remainder of the river course can be rated. Using this method, a large river stretch can be assessed in a relatively short period while still retrieving high quality data for the total river course. In this way, models with high data requirements for assessing the condition of a river course, can be parameterised without major investments on field surveys.In a small headwater catchment (23 km 2 ) in southwestern Poland, this field methodology was used to retrieve data to run an existing model (HEC-GeoRAS) which can assess the impact of changes in the riparian and channel vegetation and channel management on sedimentation processes and stream flow velocity. This model determines the impact of channel morphology and in-channel and riparian vegetation on stream flow and sediment transport. Using four return periods of flooding (2, 10, 20 and 100 years), two opposing channel management / morphology scenarios were run; a natural channel and a fully regulated channel. The modelling results show an increase in the effect of riparian vegetation / geomorphology with an increase in return period of the modeled peak discharge. More natural channel form and increased roughness reduces the stream flow velocity due to increasing drag from flow obstructions (vegetation and channel morphological features). The higher the flood water stage, the greater the drag due to vegetation on the floodplains of natural river reaches compared to channelised sections. Slower flow rates have an impact on sediment mobilisation and transport in the river.

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Channelization of the severely polluted Odra and Vistula Rivers in Poland induced intensive accumulation of finegrained deposits rich in organic matter and heavy metals. These sediments have been identified in vertical profiles in a narrow zone along river banks both in groyne-created basins and on the floodplain. Grain size, organic matter, zinc (Zn), lead (Pb), copper (Cu) content and cesium-137 ( 137 Cs) was used for sediment dating and, stratigraphy and chemistry have been diagnostic features for these deposits, named industrial alluvium. In the most polluted river reaches stabilized by bank reinforcements and groynes, 2-m-thick slack water groyne deposits are composed of uniform strata of polluted silts with organic matter content over 10%, Zn content over 1000 mg/kg and average Cu and Pb over 100 mg/kg. The average rate of sediment accretion in groynes is higher than on the floodplain and reaches 5 cm/yr. Stratification which appears at higher levels in the groyne fields and on the levees reflects a change from in-channel to overbank deposition and is typified by dark layers separated by bright, sandy, and less polluted strata. Stratified, 4-mthick, sediment sequences have been found in groyne fields of incised river reaches. The average rate of sediment accretion in these reaches is of the order of 5 cm/yr. In stable and relatively less polluted river reaches, vertical-accretion organic deposits are finely laminated and the average rate of deposition amounts to a few millimeters per year. Investigations indicate that groyne construction favors conditions for long-term storage of sediments at channel banks. For this reason, groynes should be considered as structures that efficiently limit sudden release of sediment-associated heavy metals stored in channels and in floodplains of the historically polluted rivers.

The Sudety Mts. form a chain of mountains in the South of Poland and during the last 200 years were subjected to strong industrial and agricultural pressure. The records of these human-induced changes are stored in natural archives like lake sediments. For the comprehensive study, three sediment cores taken from Mały Staw Lake (Sudety Mts.) were analyzed for the concentration of K, Na, Mn, Fe, Cu, Mg, Zn, Cd, Cr, Ni, Pb and radioactivity of 137Cs and 210Pb. As a result of the studies, the bathymetry map was developed and the sources of solid material supplied to the lake were identified. The geochronology studies of the cores were performed using 210Pb method, to evaluate model of time changes in the sediment. Radioactivity of 210Pbuns (determined indirectly by 210Po) ranged from 1051 ± 64 to 12 ± 8 Bq kg−1. The 137Cs radioactivity was determined directly by gamma spectrometry and varied from 525 ± 37 Bq kg−1 for top layers to 9.80 ± 5.40 Bq kg−1 for the bottom of the core. Two characteristic peaks of 137Cs radioactivity related to the global fallouts after nuclear weapons testing and the Chernobyl accident were observed and used to confirm 210Pb dating method. Chemometrics analysis of the chosen metal’s concentrations combined with sample dating showed distinct imprint of human activity on the studied area.

As an anthropogenic element of urban landscapes, coal heaps undergo changes due to both natural and anthropogenic factors. The aim of this study was to determine the common development of soil under the influence of vegetation succession against a background of environmental conditions. Vegetation changes and soil properties were analysed along a transect passing through a heap representing a particular succession stage. It was found that changes in the development of vegetation were closely related to the stages of coal-waste disposal, where the initial, transitional, and terminal stages were distinguished. The mean range of pH (H2O) values in the profiles was 6.75 ± 0.21 (profile 1), 7.2 ± 0.31 (profile 2), 6.3 ± 1.22 (profile 3), and 5.38 ± 0.42 (profile 4). The organic carbon (OC) content in all samples was high, ranging from 9.6% to 41.6%. The highest content of total nitrogen (Nt) was found (1.132%) in the algal crust and sub-horizon of the organic horizon (Olfh-0.751%) and humus (A-0.884) horizon in profile 3 under the initial forest. Notable contents of available elements were found in the algal shell for P (1588 mg∙kg−1) and Mg (670 mg∙kg−1). Soil organic matter content was mainly dominated by n-alkanes (n-C11-n-C34) and alkanoic acids (C5–C20). Phytene and Phytadiene were typical for the algal crust on the initial pedigree. The initiation of succession was determined by the variation in grain size of the waste dumped on the heap and the variation in relief and associated habitat mosaic. Algal crusts forming on clay–dust mineral and organic material accumulating in the depressions of the site and at the foot of the heap can be regarded as the focus of pedogenesis.

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The aim of the studies presented in this article was a multifaceted approach to the problem of the processes of river adjustments to new conditions created by channel regulation. The Upper Odra channel has been significantly shortened by meander cut offs and locally by channelization. The influence of those changes on channel morphodynamics and the pattern of bedload transport were calculated. Pre-regulation channel geometry was reconstructed and the channel stability and bedload transport were characterized and compared with the present state. Also the flow duration curves (FDC) for the characteristic water stages and for the average discharges were plotted and analyzed to assess vertical channel bed movement. By comparing the behavior of natural channel sectors (both, present and fossil) to channelized and sectors shortened by cut offs it was possible to understand the intensity of changes depending on a way of channel regulation. The range of post regulation changes in bedload transport and channel stability was also calculated for the functioning, unregulated sector of the Odra channel. Flow duration curves reflect steady channel incision while the protected river banks prevent the channel from lateral movement. In order to achieve lateral stability, which is unnatural for meandering rivers, the Odra channel is totally remodelled and the new geometry and flow conditions created. The morphological response to the training works was channel incision and accelerated bedload transport.

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