This study sought to establish a quantitative functional hydrogeomorphological typology of river reference types in the French Upper Rhine basin that would meet the requirements of the European Water Framework Directive, defined in terms of hydromorphological quality and prospects for river restoration. Four ecoregions (i.e. hydrogeomorphic units) were delineated by expert opinion and validated by independent variables (i.e. 1·5-year peak discharge, comparison of 10-year daily flow and low flow, valley bottom morphology and specific stream power). A data set of 31 quantitative and qualitative variables for 187 field sites was established and analysed. Agglomerative hierarchical clustering (AHC) of the quantitative variables and principal component analysis (PCA) provided hierarchy and grouping of variables. Multiple correspondence analysis (MCA) confirmed these results, discriminating sites into seven groups, but did not lead to a functional typology due to important overlapping between groups and variability within groups. A definitive quantitative typology was obtained through AHC and discriminant analysis with cross-validation computed separately in each ecoregion. Results for two ecoregions, 'marly calcareous loess-covered hills' and 'crystalline Vosges mountains', are given as examples. Finally, the classification of the sites is extended to the whole river network by river sectorization, each homogeneous river section being classified to one category on the basis of the preceding classification of sites. Methodological implications regarding river classification are also given.WFD only suggests possible criterion for river classification (altitude, geology, energy, valley and channel morphology, sediment transport etc.). Each country has to elaborate its own operational method.A large array of methods for hydrogeomorphological typologies can be found in the literature. This range of approaches is related to various objectives, which are often linked to specific management problems, various scales and different geographical settings (Kondolf et al., 2003). Many authors have tried to highlight the principles and results of these numerous approaches through several bibliographic syntheses (Hawkes

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The hydraulic management works, carried out on the Rhine over about 150 years, have suppressed a large part of the Rhine floodplains and thus dramatically modified the environmental conditions of alluvial ecosystems. The Offendorf alluvial forest situated 30 km north of Strasbourg, of which 60 ha are now a nature reserve, is taken as an example of a restoration programme to attain “the most natural possible” ecosystem functioning. The general status of the Offendorf forest hydrographic network is mesotrophic to eutrophic, due to the water supply. Some diffluent arms present a tendency to silt up, because of the lowering of the water table. Thus a first step in the restoration programme was to re-establish the continuity of surface flow, in low as well as in high water, taking into account the water quality. But the accurate context of the restoration is that of a naturally functional unit, i.e. the whole extent of the forest lying between the high water dykes and not the limited sector within the administrative boundaries of the nature reserve. A definition of a restoration programme is proposed: the renaturalizing of the riverside environments should comprise several stages from study of the past or present processes to prediction of new modifications.

Следы четвертичной эволюции в нижней долине Брюши. На западе от Страсбура в конусе предгорья Брюши, эта работа различает присутствие многоярусных террас. Автор пробует определить их возраст и восстановить при помощи изучения существующих разрезов ибуровых скважин геоморфоло гическую эволюцию этого района в четвертичную эпоху. Он подчеркивает возможность существования тектонических движений в недавнюю четвертичную эпоху. Автор лока¬ лизует несколько линий разрыва, он также анализирует положение настоящих рек по отношению к геоморфологическим элементам, которые были предварительно установлены и объясняет некоторые аномалии в этом вопросе.