Search results for "Floodplain"
showing 10 items of 37 documents
Nemastoma bidentatum (Arachnida: Opiliones: Nemastomatidae): neu für Deutschland und die Tschechische Republik
2007
Nemastoma bidentatum (Arachnida: Opiliones: Nemastomatidae): first records for Germany and the Czech Republic. N. bidentatum Roewer, 1914 was found at two places in Germany: first on the island "Harriersand" in the Weser river (Lower Saxony), second on the banks of the river Elbe in the Elbsandsteingebirge (Saxony). Adjacent to the latter locality an occurrence in the Czech Republic could be located close to the German/Czech border in the floodplain of the river Elbe as well. These records are the first for Germany and the Czech Republic. They enlarge the distribution area of N. bidentatum remarkably in both a northern and a western direction. The two populations show conspicuous difference…
Sedimentología y paleontología del yacimiento Finimioceno de La Portera (Valencia)
1986
14 páginas, 8 figuras, 1 tabla, 1 lámina.
The formation of alluvial fans and young floodplain deposits in the Lieser catchment, Eifel Mountains, western German Uplands: A study of soil erosio…
2011
This study deals with the exploration and spatiotemporal quantification of the young Holocene, nearly skeleton-free floodplain sediments of the Lieser River, a tributary of the Mosel River in the Eifel Mts. The deposits are primarily a consequence of anthropogenic-triggered soil erosion in the catchment. To observe the phenomenon of corresponding soil erosion on multiple levels two small alluvial fans of tributary catchments were investigated. For comparison, one location in the neighboring Salm valley was described. The results were compared with those of other streams. With extensive fieldwork more than 100 drillings and pits were made at 12 locations. For dating the sediments OSL dating…
Budgeting soil erosion from floodplain sediments of the central Rhenish Slate Mountains (Westerwald), Germany
2011
The distribution, thickness and composition of the floodplain sediments in the valleys of the Gelbach (Lower Westerwald) and Große Nister (Upper Westerwald) depend on the occurrence of loessic periglacial cover beds in their catchments as well as on historical land use. The budget of floodplain sedimentation was derived from a study of the floodloams underlying the monastery garden of Marienstatt, a village in the Große Nister valley. From the study of two occupation levels, pottery shards and radiocarbon dating, 55% of the floodloam can be attributed to the Modern period (younger than c. AD 1450). From the radiocarbon age of a charcoal fragment extracted from the base of the floodloam at …
Variabilidad espacial de los cambios de cauce en una rambla mediterránea en las seis últimas décadas (1946-2006)
2014
An analysis of morphological changes during the last six decades is presented for the Rambla de Cervera, a Mediterranean ephemeral stream located in the eastern sector of the Iberian Mountain Range. The studied channel (16.5 km) has two contrasted sectors: a horst confined sector (5.5 km) and a graben sector (11 km). Channel changes were analysed through the analysis of aerial photographs, with geographical information systems (GIS) and comparison of topographic surveys made with a GPS-RTK. Between 1946 and 2006 the Rambla de Cervera, underwent channel adjustments comparable to those observed in other Mediterranean rivers. The gravel channel markedly narrowed, losing width (68.5%) and chann…
Pedogenesis and Variability in Soil Properties in a Floodplain of a Semiarid Environment in Southwestern Sicily (Italy).
2010
We performed a pedological study of the variability in soils in a floodplain area of a semiarid region in southwestern Sicily. The objectives of our research were to (i) investigate the role of parent material, erosion, and distribution processes on soil pedogenesis and horizon differentiation; (ii) evaluate the statistical distribution of soil properties; and (iii) interpret these distributions in terms of pedogenic and other processes. Our results showed that not all soil properties examined followed a normal distribution and that even when logtransformed, the degree of normality of the soil salinity data did not improve. Furthermore, principal component analysis was performed to investig…
Using post-flood surveys and geomorphologic mapping to evaluate hydrological and hydraulic models: The flash flood of the Girona River (Spain) in 2007
2016
This paper analyzes the Girona River (Spain) flash flood, occurred on the 12th of October 2007, combining hydrological and hydraulic modeling with geomorphologic mapping and post-flood survey information. This research aims to reproduce the flood event in order to understand and decipher the flood processes and dynamics on a system of prograding alluvial fans. The hydrological model TETIS was used to characterize the shape and dimension of the October 2007 Girona River hydrograph. Subsequently, the flood event was reproduced using the free surface flow module of the model RiverFlow2D. The combination of hydrological and hydraulic models was evaluated using post-flood surveys defining maximu…
Historical morphogenesis of the Turia River coastal flood plain in the Mediterranean littoral of Spain
2011
Abstract The cross-referencing of sedimentological, stratigraphic, geoarchaeological and radiocarbon data enables us to establish the geomorphologic evolution of the Late Holocene coastal flood plain of the Turia River. The Holocene marine transgression formed a coastal barrier lagoon environment in the coastal plain. During the Late Holocene, increased sediments supplied to the low reach of the river promoted: (a): the progradation of deltaic coastal sandy ridges on the coastline and (b): the aggradation of the floodplain on top of the sedimentary sequence. Four phases are clearly recognised in the geoarchaeological record of the flood plain. (1): High magnitude flooding events (2800 BP to…
Human induced soil erosion and gully system development in the Late Holocene and future perspectives on landscape evolution: The Myjava Hill Land, Sl…
2013
In humid climate zones, like Central Europe, past soil erosion and gullying are strongly connected with agricultural expansion, and extreme soil erosion events often play an important role in land abandonment. This paper provides a case study to demonstrate the interaction between land use, soil erosion, floodplain development, and land use changes in a 0-order catchment in the Babikovce catchment, Myjava Hill Land, situated in western Slovakia. Sedimentological, pedological, geoarchaeological and historical data indicate two main periods of intensive hillslope erosion and gullying since the High Middle Ages. In particular, a few extreme precipitation events (or rapid snowmelts) caused inte…
Flood pattern changes in the rivers of the Baltic countries
2015
Estimation of both the frequency and variation of spring floods is a key issue for the assessment and management of flood risks. Changes in river floods in Estonia, Latvia and Lithuania have been investigated in few national studies. However, there are no studies of the changes of flood patterns by using a common methodology for the rivers of this region. In this study flood pattern changes in the rivers of the Baltic countries were estimated applying trend and frequency analysis for the periods of 1922–2010, 1922–1960, 1961–2010 and 1991–2010, i.e. for the whole spring flood data sets, periods before and after 1960 (this year was considered as the beginning of the remarkable climate change…