scholarly journals SECULAR CHANGE IN TIDAL FLAT HEIGHTS

1988 ◽  
Vol 1 (21) ◽  
pp. 132
Author(s):  
Winfried Siefert
Keyword(s):  
Morphological Analysis ◽  
Tidal Flats ◽  
Coastal Engineering ◽  
Secular Change ◽  
Coastal Protection ◽  
Mean Sea Level ◽  
The Mean ◽  
High Level ◽  
Sea Coast ◽  
North Sea Coast

The German North Sea Coast is relatively short (370 km); its shape is extremely irregular with estuaries, extended tidal flats, partly protected by sandy islands with deep tidal gullies between them (Fig. 1). In order to gain more detailed information and sufficient knowledge about the variety and variations in this region, the German Coastal Engineering Board (KFKI, Kuratorium fur Forschung im Kusteningenieurwesen) has initiated a high-level and extensive programme, "MORAN", "Morphological Analysis Klorth-Sea-Coast". The purpose and the first ideas of the programme were presented by Siefert and Barthel (1981). Investigations are still under way. It is of high interest whether the mean height of the tidal flats will rise, if the green house effect results in an acceleration of the mean sea level rise. In that case coastal protection in areas behind tidal flats will have to be changed completely, as then wave energy will no longer be dissipated in front of the coastline and will attack the dikes heavily .

scholarly journals MORPHOLOGICAL REACTIONS OF TIDAL SYSTEMS DUE TO NEARSHORE CONSTRUCTION WORKS

1982 ◽  
Vol 1 (18) ◽  
pp. 150 ◽  
Author(s):  
R. Dieckmann ◽  
H.W. Partenscky ◽  
H. Schwarze
Keyword(s):  
Coastal Area ◽  
Storm Surges ◽  
Tidal Flats ◽  
Coastal Protection ◽  
Large Area ◽  
The Past ◽  
The North ◽  
Sea Coast ◽  
North Sea Coast ◽  
Construction Works

The nearshore region of the North German North Sea coast is characterised by a large area of tidal flats with a width of 10 to 30 km (Fig. 1) . The development of the structure of this coastal area in the past centuries was mainly determined by several severe storm surges, which have destroyed the formerly existing coastline. In its present state the coastal area is subdived into numerous tidal flats, islands and peninsulas of different size and more or less deep channels and small gullies. Due to its historical development, this area cannot be expected to be morphologically stable. Once people learnt to build safe dikes, the coastline existing at the time was fixed whilst the islands in the shore belt were protected against flooding during storm surges. However, the shore belt is furthermore exposed to waves and tidal currents which cause - apart from certain shlftings of gullies - extensive permanent erosion and sedimentation in parts of the shore belt with an increasing tendency in the last decades. The nearshore region at some places on the coast is extremely endangered in its function as part of the coastal protection system, consisting of the dike, the foreshore above MHW and the tidal flat area. First attempts to achieve morphological stabilisation of the nearshore region consisted in the construction of dams normal to the coastline. However, the shore belt still remained morphologically unstable and could not yet be transformed into a stable system.

scholarly journals Dual-Frequency Airborne SAR for Large Scale Mapping of Tidal Flats

2020 ◽  
Vol 12 (11) ◽  
pp. 1827 ◽  
Author(s):  
Muriel Pinheiro ◽  
Joel Amao-Oliva ◽  
Rolf Scheiber ◽  
Marc Jaeger ◽  
Ralf Horn ◽  
...  
Keyword(s):  
Large Scale ◽  
Tidal Flats ◽  
Dual Frequency ◽  
Digital Elevation ◽  
First Results ◽  
Data Source ◽  
Airborne Sar ◽  
Flooded Areas ◽  
Sea Coast ◽  
North Sea Coast

Digital elevation models of tidal flats are a most valuable data source for the water management of coastal areas and need frequent updates to account for changes in sedimentation, erosion and identification of damages in building infrastructure. This paper presents the conceptual design, the processing methodology and first results of an airborne SAR campaign conducted in July 2019 at the German North Sea coast, showing the potential for accurate monitoring of height changes at decimeter level in mudflat areas, as well as indication of vegetation cover and water flooded areas.

scholarly journals MEASURES AGAINST EROSION AT GROINS AND JETTIES

2000 ◽  
Vol 1 (3) ◽  
pp. 11
Author(s):  
Per Brunn
Keyword(s):  
North Sea ◽  
Main Part ◽  
Special Consideration ◽  
Coastal Protection ◽  
Littoral Drift ◽  
Sea Coast ◽  
North Sea Coast

One of the difficult problems on a littoral drift coast is the erosion on the leeside of groins and jetties. This paper will deal with the problem giving special consideration to the conditions on the Danish North Sea coast where many interesting problems of littoral drift and coastal protection are found. They are discussed as an introduction to the main part of the paper which is principally concerned with leeside erosion and measures for its prevention.

scholarly journals DYNAMICS AND MORPHOLOGY OF SAND BANKS IN THE SURF ZONE OF OUTER TIDAL FLATS

1974 ◽  
Vol 1 (14) ◽  
pp. 50
Author(s):  
Harald Gohren
Keyword(s):  
North Sea ◽  
Surf Zone ◽  
Tidal Flats ◽  
Wind Drift ◽  
Side Slope ◽  
Set Up ◽  
Strong Erosion ◽  
Crest Height ◽  
Sea Coast ◽  
North Sea Coast

Extended sand banks ranging up to some hundred acres with a crest height in the MHW-level are typical structures of the outer tidal flats of the south-eastern North Sea coast (Fig. 1). Primary forms grow up in the surf zone at the sea-side tidal flat border. They are formed like bars and migrate towards the coast with a surprisingly high velocity, up to 150 m/year. The movement is caused by strong erosion on the sea-side slope - which is shaped beach-like - and deposition at the steeper land-side (lee-side) slope. It was found that surf action at the bar is linked with strong unidirectional currents across the crest, Up to 100 cm/s. The currents are most likely generated by wave set-up in front of the bank and by wind-drift water motion.

scholarly journals NEW ASPECTS CONCERNING THE INCREASE OF SEA LEVEL ON THE GERMAN NORTH SEA COAST

1984 ◽  
Vol 1 (19) ◽  
pp. 61
Author(s):  
Hans Rohde
Keyword(s):  
International Cooperation ◽  
Sea Level ◽  
North Sea ◽  
Climate Changes ◽  
Coastal Engineering ◽  
Contributing Factors ◽  
Steep Rise ◽  
Scientific Disciplines ◽  
Sea Coast ◽  
North Sea Coast

The development of MThw on the German North Sea coast is probably related to the development of the climate. Other important contributing factors are discussed. For the last 20 years a relatively steep rise of MThw level is recognizable. An even steeper rise as a result of climate changes appears possible within the next 100 years. With regard to the great importance for coastal engineering, the necessity of attentive observation and international cooperation among different scientific disciplines is stressed.

DFT Benchmark Study of the O--O Bond Dissociation Energy in Peroxides Validated with High-Level Ab-Initio Calculations

2019 ◽  
Author(s):  
Danilo Carmona ◽  
Pablo Jaque ◽  
Esteban Vöhringer-Martinez
Keyword(s):  
Reference Value ◽  
Basis Set ◽  
Basis Sets ◽  
Mean Deviation ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
The Mean ◽  
Experimental Values ◽  
High Level ◽  
Almost All

<div><div><div><p>Peroxides play a central role in many chemical and biological pro- cesses such as the Fenton reaction. The relevance of these compounds lies in the low stability of the O–O bond which upon dissociation results in radical species able to initiate various chemical or biological processes. In this work, a set of 64 DFT functional-basis set combinations has been validated in terms of their capability to describe bond dissociation energies (BDE) for the O–O bond in a database of 14 ROOH peroxides for which experimental values ofBDE are available. Moreover, the electronic contributions to the BDE were obtained for four of the peroxides and the anion H2O2− at the CBS limit at CCSD(T) level with Dunning’s basis sets up to triple–ζ quality provid- ing a reference value for the hydrogen peroxide anion as a model. Almost all the functionals considered here yielded mean absolute deviations around 5.0 kcal mol−1. The smallest values were observed for the ωB97 family and the Minnesota M11 functional with a marked basis set dependence. Despite the mean deviation, order relations among BDE experimental values of peroxides were also considered. The ωB97 family was able to reproduce the relations correctly whereas other functionals presented a marked dependence on the chemical nature of the R group. Interestingly, M11 functional did not show a very good agreement with the established order despite its good performance in the mean error. The obtained results support the use of similar validation strategies for proper prediction of BDE or other molecular properties by DF Tmethods in subsequent related studies.</p></div></div></div>

The way of value of Correlation of genomic DNA microsatellite loci and live weight of Chukchi reindeer

2020 ◽  
pp. 27-32
Author(s):  
V. Dodokhov ◽  
N. Pavlova ◽  
T. Rumyantseva ◽  
L. Kalashnikova
Keyword(s):  
Microsatellite Markers ◽  
Agricultural Production ◽  
Live Weight ◽  
Biodiversity Loss ◽  
Tribal Community ◽  
High Germination ◽  
Wide Range ◽  
The Mean ◽  
High Level ◽  
Dna Microsatellite

The article presents the genetic characteristic of the Chukchi reindeer breed. The object of the study was of the Chukchi reindeer. In recent years, the number of reindeer of the Chukchi breed has declined sharply. Reduced reindeer numbers could lead to biodiversity loss. The Chukchi breed of deer has good meat qualities, has high germination viability and is adapted in adverse tundra conditions of Yakutia. Herding of the Chukchi breed of deer in Yakutia are engaged only in the Nizhnekolymsky district. There are four generic communities and the largest of which is the agricultural production cooperative of nomadic tribal community «Turvaurgin», which was chosen to assess the genetic processes of breed using microsatellite markers: Rt6, BMS1788, Rt 30, Rt1, Rt9, FCB193, Rt7, BMS745, C 143, Rt24, OheQ, C217, C32, NVHRT16, T40, C276. It was found that microsatellite markers have a wide range of alleles and generally have a high informative value for identifying of genetic differences between animals and groups of animal. The number of identified alleles is one of the indicators of the genetic diversity of the population. The total number of detected alleles was 127. The Chukchi breed of deer is characterized by a high level of heterozygosity, and the random crossing system prevails over inbreeding in the population. On average, there were 7.9 alleles (Na) per locus, and the mean number of effective alleles (Ne) was 4.1. The index of fixation averaged 0.001. The polymorphism index (PIC) ranged from 0.217 to 0.946, with an average of 0.695.

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