Gravel-Pit Lakes Connected with the River Rhine as a Reserve for High Productivity of Plankton and Young Fish

1994 ◽  
Vol 29 (3) ◽  
pp. 267-271 ◽  
Author(s):  
D. Neumann ◽  
Chr Seidenberg-Busse ◽  
A. Petermeier ◽  
St Staas ◽  
F. Molls ◽  
...  
Keyword(s):  
Flood Plain ◽  
River Rhine ◽  
Flood Events ◽  
Eutrophic Lakes ◽  
Field Station ◽  
High Productivity ◽  
Sand And Gravel ◽  
The University ◽  
Lentic Waters ◽  
Lower Rhine

During the last two decades an increasing number of sand and gravel-pits were established in the original flood plain of the River Rhine. Some of these are connected with the stream by a small canal for the transport of the spoil. Some of these dredged lakes have been studied during recent years at the ecological field station of the University of Köln, with regard to seasonal phytoplankton succession, productivity of copepods and cladocerans, occurrence of macrozoobenthos, and both spawning and recruitment of fish populations. These eutrophic lakes represent a valuable substitute biotope for lost lentic waters of the former flood plain. They offer via the canal connection an advantageous habitat to resident fish species of the Lower Rhine, (1) for reproduction and growth of the 0+-generation, and (2) for shelter during flood events. Recommendations for reclamation plans of such lakes are required.

Bed Degradation – Nature, Causes, Countermeasures

1994 ◽  
Vol 29 (3) ◽  
pp. 325-333 ◽  
Author(s):  
E. Gölz
Keyword(s):  
Flood Plain ◽  
Bed Load ◽  
River Rhine ◽  
River Engineering ◽  
Morphological Process ◽  
River Bed ◽  
Degradation Rates ◽  
River Training ◽  
Abandoned Channels ◽  
Lower Rhine

Bed degradation is the dominant morphological process along the freely flowing river Rhine between Iffezheim and the German-Dutch border with degradation rates varying between 5 and 50 mm year1. As a continuing bed degradation may cause severe economical and ecological damage, nature, causes and extent of degradation have been studied using two diving bell watercraft. Additional petrographic examinations of bed sediments as well as bed load measurements have revealed that bed degradation of the Lower Rhine is mainly caused by bed load deficits due to the specific morphotectonic conditions as well as anthropogenic interference, especially impounding of the big tributaries. Low degradation rates are a precondition for certain rehabilitation measures as, e.g. restoring of flood plain areas and reactivation of abandoned channels and meander belts. Therefore stabilisation of the river bed is an important task for ecological river engineering. For the river Rhine a stabilisation strategy is suggested combining conventional river training works, maintenance measures and artificial bed load supply.

scholarly journals Omnivorous Behaviour of the Agouti (Dasyprocta leporina): A Neotropical Rodent with the Potential for Domestication

Scientifica ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Kegan Romelle Jones ◽  
Kavita Ranjeeta Lall ◽  
Gary Wayne Garcia
Keyword(s):  
Rural Communities ◽  
Trinidad And Tobago ◽  
Short Communication ◽  
Nutrient Requirements ◽  
The West ◽  
Field Station ◽  
Zenaida Macroura ◽  
Neotropical Rodent ◽  
The University ◽  
First Time

The agouti is a Neotropical rodent which is mainly utilized for its meat in rural communities. Recently, captive rearing of these animals by wildlife farmers have increased in the Neotropics. This short communication consists of observation of feeding behaviour of captive reared agoutis at the University of the West Indies Field Station in Trinidad and Tobago. This is the first time in Trinidad and Tobago that meat consumption and the omnivorous behaviour of the agouti have been documented in the literature. The consumption of chicken (Gallus domesticus) eggs, dead chickens, and a brown dove (Zenaida macroura) by captive reared agoutis was noted. This document described the omnivorous behaviour of the agouti which is primarily considered a frugivorous animal. Similar studies in South America have shown that wild and captive reared agoutis consumed animal matter. Further work must be done on the dietary needs and nutrient requirements of the agouti at different physiological states.

Genetic variation between and within two populations of Trifolium glomeratum (cluster clover) in Western Australia

1997 ◽  
Vol 48 (7) ◽  
pp. 969 ◽  
Author(s):  
Sarita Jane Bennett
Keyword(s):  
Cluster Analysis ◽  
Genetic Variation ◽  
Western Australia ◽  
Morphological Characters ◽  
Field Station ◽  
Site Variation ◽  
Components Analysis ◽  
And Cluster Analysis ◽  
The University ◽  
Two Populations

Genetic variation between and within populations of Trifolium glomeratum (cluster clover) was studied using seed collected from 2 sites in Western Australia: Mount Barker in the south and Kwelkan in the wheatbelt. Seed was collected at 64 subplots within each site and the material was grown at the University Field Station at Shenton Park, Perth. Seventeen morphological characters were scored and the results were analysed using analysis of variance, principal components analysis, and cluster analysis. Within-site variation was much greater than had previously been shown, and a considerable amount of between-site variation was present. It is suggested that within-site variation is due to a small amount of heterozygosity, as a result of limited outbreeding, being present in each population. The 2 populations are shown to be distinct from each other, with the population from Mount Barker containing more within-site variation. It is suggested that this is a result of climatic stress influencing and reducing the amount of variation being maintained in the Kwelkan population.

Parameter optimization in modelling unsteady compound channel flows

1992 ◽  
Vol 19 (3) ◽  
pp. 441-446 ◽  
Author(s):  
Habib Abida ◽  
Ronald D. Townsend
Keyword(s):  
Parameter Optimization ◽  
Optimization Methods ◽  
Flood Plain ◽  
Flood Routing ◽  
Compound Channel ◽  
Flood Events ◽  
Channel Section ◽  
Simplex Methods ◽  
Boundary Roughness ◽  
Good Agreement

Optimization methods are used to estimate data for routing floods through open compound channels (main channels with flood plain zones). These data include the irregular channel section geometry and the varying boundary roughness. Differences between simulated and observed stages and discharges are minimized using three optimization algorithms: Powell's method, Rosenbrock's algorithm, and the Nelder and Meade simplex method. Powells' method performed poorly; however, both the Rosenbrock and simplex methods yielded good results. The estimated data using the Rosenbrock and simplex methods were used to route different flood events observed in a laboratory channel. Simulated peak stages and discharges were in good agreement with those estimated using actual routing data. Key words: compound channel, flood routing, lateral momentum transfer, optimization, unsteady flow.

scholarly journals Biostratigraphy and paleoecology of continental Tertiary vertebrate faunas in the Lower Rhine Embayment (NW-Germany)

2002 ◽  
Vol 81 (2) ◽  
pp. 177-183 ◽  
Author(s):  
Th. Mörs
Keyword(s):  
Depositional Environment ◽  
Middle Miocene ◽  
Flood Plain ◽  
Nw Germany ◽  
Climate Conditions ◽  
Faunal Assemblages ◽  
Tectonically Active ◽  
Lake Deposits ◽  
Lower Rhine Embayment ◽  
Lower Rhine

AbstractThis paper discusses the faunal content, the mammal biostratigraphy, and the environmental ecology of three important continental Tertiary vertebrate faunas from the Lower Rhine Embayment. The sites investigated are Rott (MP 30, Late Oligocene), Hambach 6C (MN 5, Middle Miocene), Frechen and Hambach 11 (both MN 16, Late Pliocene). Comparative analysis of the entire faunas shows the assemblages to exhibit many conformities in their general composition, presumably resulting from their preference for wet lowlands. It appears that very similar environmental conditions for vertebrates reoccurred during at least 20 Ma although the sites are located in a tectonically active region with high subsidence rates. Differences in the faunal composition are partly due to local differences in the depositional environment of the sites: lake deposits at the margin of the embayment (Rott), coal swamp and estuarine conditions in the centre of the embayment (Hambach 6C), and flood plain environments with small rivulets (Frechen and Hambach 11). The composition of the faunal assemblages (diversity and taxonomy) also documents faunal turnovers with extinctions and immigrations (Oligocene/Miocene and postMiddle Miocene), as a result of changing climate conditions.Additional vertebrate faunal data were retrieved from two new assemblages collected from younger strata at the Hambach mine (Hambach 11C and 14). They are important for the understanding of the Plio-Pleistocene transition in the southern part of the Lower Rhine Embayment and for correlating depositional sequences in the Dutch/German borderland.

scholarly journals Flood reconstruction using botanical evidence in Rapentosa catchment, in Marathon, Greece.

2016 ◽  
Vol 47 (3) ◽  
pp. 1388 ◽  
Author(s):  
N. Diakakis
Keyword(s):  
Flash Flood ◽  
Flood Plain ◽  
Hydraulic Modeling ◽  
Documentary Evidence ◽  
Flood Events ◽  
Instrumental Data ◽  
The Past ◽  
Increment Borer ◽  
Water Stage ◽  
Flood Analysis

Botanical evidence has been used in the past  for flash flood analysis, especially when instrumental data were scarce. This work focuses on the use of such evidence as a tool to study flash flood phenomena in Rapentosa torrent, in Marathon, Greece. To this aim, impact scars induced during past flood events    on trees along the torrent  , were  considered water stage indicators and were used   to determine discharge magnitude of these flow episodes. Samples extracted from the scarred specimens with the aid  of an increment borer, were used to date these impacts wounds. 1-D h y-draulic  modeling  was  used  to  provide  a  reconstruction  of  the  highest-discharge event, while results were cross-examined with    historical damages to verify the out-come of the analysis. Analysis showed a total of 22 impact wounds along the torrent indicating discharge values between 17.1 m3/s and 84.9 m3/s during past flow episodes. Three flash flood events were identified in 1996, 1998 and 2001. Hydraulic modeling of the 2001 event, which presented the highest flow values, illustrated its extent    and water depth across    the  flood  plain, presenting good correlation with the available documentary evidence.

scholarly journals Late Oligocene macrofloras from fluviatile siliciclastic facies of the Köln Formation at the south-eastern border of the Lower Rhine Embayment (North Rhine-Westphalia, Germany)

2016 ◽  
Vol 56 (1) ◽  
pp. 41-64 ◽  
Author(s):  
Heinrich Winterscheid ◽  
Zlatko Kvaček
Keyword(s):  
Riparian Forest ◽  
Flood Plain ◽  
Volcanic Field ◽  
Late Oligocene ◽  
The South ◽  
South Eastern ◽  
Eastern Border ◽  
Leaf Remains ◽  
Lower Rhine Embayment ◽  
Lower Rhine

Abstract The leaf remains described herein came from the oldest sites of the Cainozoic deposits in the Lower Rhine Embayment, located in the Siebengebirge Volcanic Field at the south-eastern border of this basin, in the area of Siebengebirge and vicinity. These revisited floras are bound to pre-volcanic siliciclastic facies of the Siebengebirge Mts., interpreted as marginal facies of the Köln Formation. Chronostratigraphically they are assigned to the late Oligocene (Chattian). The described leaf remains are partially compressions with preserved epidermal anatomy, and therefore highly useful for systematic determination of leaf impressions recovered from other localities of siliciclastic facies. On account of the epidermal characteristics of leaf compressions varying in gross morphology, the previously determined taxa Quercus goepperti, Laurus phoeboides, and Persea speciosa all fall into the abundantly represented Eotrigonobalanus furcinervis. The siliciclastic deposits originated in coastal and flood plain areas within fluviatile environments of variable deposition energy. Remains of Taxodium dubium, Eotrigonobalanus furcinervis, Populus germanica, and Daphnogene cinnamomifolia dominate among the recovered fossils. The general aspects of this plant assemblage correspond, together with their sedimentary settings, to riparian forest vegetation with mesophytic elements.

scholarly journals Rivers in the sky, flooding on the ground

2020 ◽  
Author(s):  
Monica Ionita ◽  
Viorica Nagavciuc ◽  
Bin Guan
Keyword(s):  
Atmospheric Circulation ◽  
Heavy Rainfall ◽  
Large Scale ◽  
Rhine River ◽  
Flood Events ◽  
Pressure Center ◽  
Atmospheric Rivers ◽  
Extreme Flooding ◽  
Large Scale Atmospheric Circulation ◽  
Lower Rhine

Abstract. The role of the large scale atmospheric circulation and atmospheric rivers (ARs) in producing extreme flooding and heavy rainfall events in the lower part of Rhine River catchment area is examined in this study. Analysis of the largest 10 floods in the lower Rhine, between 1817–2015, indicate that all these extreme flood peaks have been preceded up to 7 days in advance by intense moisture transport from the tropical North Atlantic basin, in the form of narrow bands, also know as atmospheric rivers. The influence of ARs on the Rhine River flood events is done via the prevailing large-scale atmospheric circulation. Most of the ARs associated with these flood events are embedded in the trailing fronts of the extratropical cyclones. The typical large scale atmospheric circulation leading to heavy rainfall and flooding in the lower Rhine is characterized by a low pressure center south of Greenland which migrates towards Europe and a stable high pressure center over the northern part of Africa and southern part of Europe. The days preceding the flood peaks, lower (upper) level convergence (divergence) is observed over the analyzed region, which is an indication of strong vertical motions and heavy rainfall. The results presented in this study offer new insights regarding the importance of tropical moisture transport as driver of extreme flooding in the lower part of Rhine River catchment area and we show for the first time that ARs are an useful tool for the identification of potential damaging floods inland Europe.

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