Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Journal of Water and Land Development

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Assessment of migration conditions for fish swimming through a semi-natural fish pass on the Nidzica River in Bronocice

Plesiński Karol K., Filipczyk Janusz M., Bień Michał M., Karadağ Mustafa

Journal of Water and Land Development

2023

no. 59

54--65

Fish passes are essential elements for maintaining continuity for migrating fish. Without them, fish would be unable to undertake migration to satisfy their basic life needs. These devices must meet a range of requirements related to the size of individual fish pass elements and the hydrodynamic parameters of the flowing water. Despite efforts, it is not always possible to meet these requirements. There are many causes of errors in the design and construction of fish passes, and each case should be assessed individually. The most severe consequence of these errors is the obstruction of fish migrating upstream. In this study, an analysis of the permeability of a semi-natural fish pass was conducted for fish. This assessment was carried out using two methods. In the first approach, the required geometric dimensions of the fish pass elements were determined based on the dimensions of individuals living in the river channel. In the second approach, the dimensions were extracted from publications dedicated to slot fish passes, as the studied object resembles such a design. The analysis revealed that the fish pass does not fulfil its intended role. All fish species living in the Nidzica River channel face difficulties in passing through the fish pass, including the brook trout, for which the object is specifically designed. The main errors stem from the design and construction, resulting in exceeded values, primarily in the hydrodynamic parameters, rendering the fish pass impassable. The study also aimed to develop corrective recommendations considering the latest scientific developments.

Using 1D and 2D computer models when predicting hydrodynamic and morphological parameters of a boulder block ramp: Poniczanka stream, Carpathians

Plesiński Karol K., Radecki-Pawlik Artur, Rivera-Trejo Fabian

Journal of Water and Land Development

2022

Special Issue

34--48

When modelling flow and/or sediment transport in streams and rivers, one must frequently use the computer software of differing levels of complexity. The level of sophistication, accuracy, and quality of results are the parameters by which models can be classified as being 1D, 2D, or 3D; it seems certain that in the future, there will also be 4D and 5D models. However, the results obtained from very sophisticated models are frequently questionable, and designers in the field of hydraulic structures must have considerable experience distinguishing important information from irrelevant information. Thus, this paper aims to investigate the effect of the selected boulder block ramp hydraulic structure at Poniczanka stream on the bed-load transport. We evaluated sediment transport using the CCHE2D numerical model. We analysed several scenarios depending on the river bed type (erodible, non-erodible, rocky) and examined the rock blocks used for hydraulic structure construction. The obtained results were compared with the Hjulström and the Shields graph, which are a classic approach for identifying fluvial processes in river channels. In addition to these two methods, numerical modelling using the 1D HEC-RAS (Hydrologic Engineering Center’s River Analysis System) modelling were conducted, which included the determination of horizontal and vertical changes to the river bed morphology of the examined section of river reach as well as providing the basic hydrodynamics parameters which, from the practical point of view, designers involved in the process of designing ramps could use.