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Transformation of the Vistula Lagoon into a canonical domain

100%

Prosnak W. J., Czesnik P. P.

Oceanologia

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2001

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tom 43

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nr 2

The paper deals with the conformal mapping of finite, plane, simply connected domains, representing oceans, lakes, estuaries, bays, lagoons, and other natural water bodies of this kind. As a rule, they are bounded by geometrically complex shorelines. The partial differential problems investigated in Oceanology and posed in such domains have turned out to be difficult to solve for at least three reasons. They follow on from the mathematical properties of the differential equations governing such problems, from the just-mentioned geometrical complexity of the domains of solution, and from the sensitivity of the solutions to boundary conditions. In view of the last reason the contours admitted as boundaries of the domains of the solution ought to be as close to the real shorelines as possible. The obviously inaccurate approximation of the shorelines by ‘staircases’, which appears rather often (cf. Catewicz & Jankowski 1983, Lin & Chandler-Wilde 1996) as a consequence of applying finite difference methods to the solution of the partial differential problems, raises serious doubts from the point of view of Numerical Fluid Mechanics. It is recalled in the paper that such inaccuracies are not unavoidable: that complicated plane domains can be transformed accurately by means of properly applied conformal mapping onto regular, canonical domains – in particular, onto discs or squares. Such a transformation is demonstrated on the rather difficult example of the Vistula Lagoon. The transformation begins with the decomposition of the domain into five plane subdomains, each one of which is eventually transformed onto a disc. Every such result is arrived at quite independently of the remaining subdomains, by means of a set of properly selected consecutive mappings. Hence, the final canonical domain consists in this case of a system of five discs which, however, within the framework of this differential problem, have to be treated as interconnected. The interconnections involve images of four segments of straight lines, separating the original subdomains. The transformations and the resulting canonical domain presented in the paper are intended to be applied to the solution of certain hydrodynamical problems concerning the Vistula Lagoon, which will be published elsewhere.

2

Soil organic matter status in agricultural soil sequence of former shoreline of disappearing Sumowskie Lakes, North-Eastern Poland

86%

Markiewicz M., Mendyk L., Gonet S. S.

Polish Journal of Soil Science

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2015

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tom 48

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nr 1

The aim of the study has been to define the stocks and the basic properties of soil organic matter in agricultural-used soil sequence located in the former shoreline of disappearing lakes. The study area is located in the catchment of the Sumowskie Lakes, the Brodnica Lake District, North-Eastern Poland. The investigations involved preparation of five soil pits located in the south-western part of the former Sumowskie Lake bottom and on the southern slope of the adjacent kame hill. The greatest soil transformation is reflected in the quality and quantity of the soil organic matter. Indexes of organic matter quality and TOC stocks are significantly changing along the studied transect. The strongly humidified organic matter is found in mursh horizons. Gyttja layers above the groundwater level have a medium humification index. Horizons saturated with water are very low humidified. TOC stocks drop along the analysed soil sequence from the biogenic plain to the top of the kame hill.

3

Application of Dean's curve to investigation of a long-term evolution of the Southern Baltic multi-bar shore profile

86%

Cerkowniak G. R., Ostrowski R., Pruszak Z.

Oceanologia

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2017

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tom 59

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nr 1

The paper presents the results of studies on the long-term evolution of the multi-bar cross-shore profiles. The analysis is focused on time-dependent variability of shoreline position, a modified parameter A of the conventional Dean's equation and a parameter F describing the amount of nearshore sediment resources in the multi-bar cross-shore profile. The study also deals with interrelationships between these quantities. The analysis is carried out using field data collected at Lubiatowo, Poland, on the dissipative shore, representative for the south Baltic. The considered coastal segment is found to be stable in the long-term scale. The results of analysis show that the parameter A can either increase or decrease together with the shoreline advance. It is concluded that the shoreline position change is a parameter unsatisfactorily representative for behaviour of the seashore. The use of the Dean's approximation for estimation of the sediment resources F on the multi-bar seashore profiles is found reasonable to eliminate the effects of peculiarities of such shores.

4

Towards effective public consultation and participation in Nigeria: lessons from shoreline management plans (SMPs) activities in England

86%

Famuditi T. O., Potts J., Bray M.

International Letters of Natural Sciences

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2014

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tom 15

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nr 1

This paper examines the shoreline management planning policy in England and its suitability for ameliorating the diverse environmental problems associated with Nigeria‟s coastal zones. It examines the success of SMPs in England since the mid-1990s and progress achieved, with the aim of understudying the current management approach that can be transferred to Nigeria to strengthen its adoption, and as a necessary corollary, implementation of the SMPs. This paper also examines key elements of the shoreline management frameworks in England and provides answers to the question: Would shoreline management planning approach in England be appropriate and feasible in Nigeria? It further concludes that many of the action plans and principles of participation should be adoptable provided that a participatory approach that involves all stakeholders including community members and relevant sectoral ministries as well as appropriate legal framework is encouraged.

5

Conformal mapping of the Gulf of Gdańsk onto a canonical domain

86%

Czesnik P. P., Prosnak W. J.

Oceanologia

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2002

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tom 44

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nr 2

The paper deals with the conformal mapping of a plane, finite, simply connected domain, representing the southern segment of the Gulf of Gdańsk, enclosed from the North by a parallel, tangential to Cape Rozewie. The segment contains the Hel Peninsula. The method of double decomposition, presented in Prosnak & Cześnik (2001), is applied to the transformation of such an original domain onto a canonical one, which consists of two separate unit discs. The first decomposition concerns the domain which is split into two adjacent subdomains by means of a segment of a straight line. The second decomposition involves two holomorphic functions, each one mapping a subdomain onto a separate disc. The decomposition consists in replacing the function by a sequence of simple ones, so that the mapping is performed step-wise. Each sequence starts with the Schwarz-Christoffel function, the last step consisting in an inversion that transforms an infinite circular domain onto a disc. The data for the problem is contained in the Annex, and is represented by two sets of rectangular coordinates defining consecutive discrete points of the contours bounding the subdomains. The solution to the problem consists of: – two sets of functions, consecutively transforming each of the subdomains; – the numerical values of the parameters of these functions; – a set of figures illustrating the consecutive transformations. The accuracy of the first, and of the penultimate transformation are given, because only in the case of these two functions do the unknown coefficients have to be determined by means of a suitable iterative process. The coefficients of all the remaining functions are evaluated from exact formulae. It should be recalled that the depth of the Gulf of Gdańsk varies considerably – from a few to 110 metres – the gradients of the bottom being rather large. Therefore, the domain of the solution for any mathematical problem describing the hydrodynamical phenomena occurring in the Gulf is usually taken to be three-dimensional. Nevertheless, the paper deals with the transformation of the free surface of the Gulf, assumed as plane. It should be emphasized that this assumption does not mean that the whole domain of the solution has to be regarded as plane.

6

Modelling nearshore hydrodynamics and circulation under the impact of high waves at the coast of Varkiza in Saronic-Athens Gulf

72%

Belibassakis K. A., Karathanasi F. E.

Oceanologia

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2017

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tom 59

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nr 3

A plethora of physical parameters, such as hydro-, litho- and morpho-dynamic char- acteristics, are essential for understanding the response of coastal systems to intense sea states in terms of sediment transport and shoreline evolution. Nowadays, numerical models are extensively applied to meet the above needs and support coastal planning and management. In the present work, a 2DH dynamic modelling system is used for simulating the hydrodynamic and meteorological/ oceanographic characteristics of the Saronic Gulf, in order to examine circulation patterns and predict sediment transport phenomena under high wave conditions at the coast of Varkiza, a sandy beach in the southern Attica, Greece. Time series of wind and wave data were used as input at the open boundaries of the model domain while the model was calibrated and validated through (linear and directional) statistical measures with respect to in situ wave measurements, since there was lack of hydrodynamic data at the site of interest.The simulation period of the model was between January 3 and February 19, 2013, with consecutive high waves in-between. The good agreement of the numerical results from the wave and hydrodynamic model with in situ measurements confirmed the suitability of the model for the support of sediment transport rates at Varkiza coastal segment. Model results reveal that there is a counter-clockwise water circulation during high waves that contribute to the erosion of the examined beach, which is also confirmed by independent field measurements.

7

Variability and correlations of shoreline and dunes on the Southern Baltic coast (CRS Lubiatowo, Poland)

72%

Pruszak Z., Ostrowski R., Schonhofer J.

Oceanologia

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2011

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tom 53

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nr 1

The paper analyses the results of field investigations into the evolution of the shoreline and dune toe positions in a multi-bar, dissipative coastal zone. The correlations between the changes in the shoreline and the dune toe range from −0.4 to 0.8. It is most often the case that the dune toe is stable while the shoreline moves. Consistent cross-shore migration is slightly more likely to happen than the divergent or convergent movements of both lines. Shoreline retreat and advance attain respective rates of 0.7 m day−1 and 0.4 m day−1. Deep-water wave energy of about 50 kJ m−1 constitutes the boundary between shore accumulation and erosion.

8

Biometrics of the swan mussel, Anodonta cygnea L., in the Southwest part of the Szczecin Lagoon in 2007

58%

Chojnacki J. C., Grzeszczyk-Kowalska A., Buczek W.

Electronic Journal of Polish Agricultural Universities. Series Fisheries

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2009

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tom 12

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nr 4

9

Preliminary assessment of coastal erosion and local community adaptation in Sayung coastal area, central Java - Indonesia

58%

Marfai M. A.

Quaestiones Geographicae

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2012

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tom 31

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nr 3

10

The stabilization and protection of shorelines using the broadleaf cattail and reed sweet grass

58%

Kowalik W., Pachuta K., Jeznach J.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2013

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tom 45

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nr 1

The article presents the results of studies on the mechanical properties of the broadleaf cattail Typha latifolia and reed sweet grass Glyceria maxima. The necessary study samples were collected from Lake Urszulewskie near Sierpc, Poland. The experiment was conducted using an Instron 5966 universal tensile strength testing machine. Tensile forces and the tensile strength of the individual parts of both plant species, i.e. below-ground stems (rhizomes), base of the stem and above-ground stems, were determined and compared with each other. The STATISTICA program was used for analysis. The calculated tensile strength values were compared to data of selected tree, shrub and plant species provided by other authors.

11

Improving management of shoreline and riparian wetland ecosystems: the case of Lake Tana catchment

51%

Wondie A.

International Journal of Ecohydrology and Hydrobiology

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2010

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tom 10

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nr 2-4

This review paper presents the results of many years’ research and field observations on ecological status of the catchment of Lake Tana in relation to the socioeconomic issues. There are a number of wetlands in Lake Tana region such as shore areas, head springs, permanent and temporary floodplains (riverine and manmade) which serve as crop production, fisheries, sand mining, wetland products harvesting, etc. Population pressure and poverty have led to more intrusive activities, which have damaged the overall natural resources. Poor management practices further restricted the basic ecological services they provide (for example climate control, nutrient retention, drinking water provision, flood protection, etc.). The most outstanding threats of the shoreline and riparian wetlands stability are agriculture, industrial pollution, drainage activities and overharvesting of wetland resources. Management strategies should comprise both biophysical and socioeconomic aspects with emphasis on issues like adoption of watershed/ecosystem approach at policy level, integration of income generation in conservation activities, sharing of responsibility/benefits among local stakeholders, institutional strengthening for environmentally and socioeconomically sustainable development of lakes.

12

Ginace plaze

44%

Pruszak Z., Ostrowski R.

Academia. Magazyn Polskiej Akademii Nauk

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2005

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nr 1

24-25

Ograniczanie wyników

Transformation of the Vistula Lagoon into a canonical domain

Soil organic matter status in agricultural soil sequence of former shoreline of disappearing Sumowskie Lakes, North-Eastern Poland

Application of Dean's curve to investigation of a long-term evolution of the Southern Baltic multi-bar shore profile

Towards effective public consultation and participation in Nigeria: lessons from shoreline management plans (SMPs) activities in England

Conformal mapping of the Gulf of Gdańsk onto a canonical domain

Modelling nearshore hydrodynamics and circulation under the impact of high waves at the coast of Varkiza in Saronic-Athens Gulf

Variability and correlations of shoreline and dunes on the Southern Baltic coast (CRS Lubiatowo, Poland)

Biometrics of the swan mussel, Anodonta cygnea L., in the Southwest part of the Szczecin Lagoon in 2007

Preliminary assessment of coastal erosion and local community adaptation in Sayung coastal area, central Java - Indonesia

The stabilization and protection of shorelines using the broadleaf cattail and reed sweet grass

Improving management of shoreline and riparian wetland ecosystems: the case of Lake Tana catchment

Ginace plaze