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Molecular detection of oomycetes species in water courses

Abstract

In Poland, about 20% of forest nurseries use irrigation water coming from natural superficial reservoirs, presumed to be the first source of infection caused by harmful pathogens belonging to the Oomycota class, especially Phytophthora genus and Pythium genus. The forest nursery is the only place where forest managers can react before pathogens leave it with asymptomatic plants or soil attached to their roots. The aim of this research was detection and identification phytopathogens in water samples. In order to recognise genus Phytophthora or Pythium in water collected from 33 places in five different forest districts in Poland, two DNA-based approaches of identification were applied: (i) the TaqMan probes, and (ii) sequencing of the ITS6/4 region.

The genomic DNA was obtained from 17 of 33 investigated water samples. TaqMan probes helped to identify 8 oomycetes present in 17 water samples. Based on ITS rDNA sequencing data, pathogens were identified in 17 cases, and this to the genus level (6 cases) and to the species level (11 cases). In total five Oomycetes species were identified, i.e. 3 Pythium species (Py. citrinum, Py. angustatum, Py. helicoides) and two Phytophthora species (P. lacustris sp. nov. - former taxon Salixsoil, P. gallica sp. nov.).

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Basic Aspects for the Ecological Restoration of Urban Water Courses

Abstract

Due to the fact that urban water courses provide precious natural and recreational areas within urban surroundings and that they contribute to an increase in quality of life, they have gained more and more importance in recent years. The restoration and planning of urban water bodies pose an enormous challenge, because most of them are in a poor ecological and structural state.

This paper deals with the questions and problems concerning the topic and presents basic aspects for the ecological restoration of urban water courses.

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The Phytoplankton Biota Variation on the TimiȘ River According to the Chemistry And Hydrology of the Water Course

ABSTRACT

The Timiș River is the biggest tributary of the Banat catchment area. It springs at an elevation of 1145 m, under Piatra Goznei peak. Due to the fact that it crosses several relief forms, its hydrology, chemistry and biological characteristics are modified in consequence.

The chemical and biological analysis of the water course and their correlation with hydrological data displayed evidence of the interdependence of these factors. The phytoplankton composition and richness are directly influenced by river’s chemistry and hydrology. In the mountain area, the flow and the speed of the watercourse are inducing a specific flora and fauna for the area. In the lower areas, the river hydrology triggers a change in the biological characteristics as the water chemistry changes. The mountain species are adapted to rocky substrata in order to resist high water velocity and pressure. In the lower areas they are replaced by lowland species adapted to larger yet slower flows.

The Timiș River is a watercourse that did not undergo major qualitative changes in terms of water quality.

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NUMERICAL MODELING OF VERTICAL WELLS IN UNSTEADY GROUNDWATER FLOW CONDITIONS

Abstract

This article presents the results of numerical calculations of drainage of a large engineering construction - “Afrykarium” in Wrocław ZOO, Poland, based on a 2D numerical model for seepage flow. In the numerical simulations the real (natural) hydrogeological conditions, water-courses, surface reservoirs and time dependent seepage flow (during drainage) are taken into account. The aim of numerical calculations was to determine quantities (draining time, number of wells, spacing and arrangement of wells, flows for every well, and hydraulic head map) necessary to design an effective drainage system of construction site. The mathematical model adopted to illustrate and predict groundwater depression during pumping was the Boussinesq equation for unsteady 2D flow.

Open access
Possibility of utilization directing structures in river revitalization

Possibility of utilization directing structures in river revitalization

Directing and concentrating structures are mainly used on water courses with unstable channels and major sediment transport or in areas with major bank erosion. The main purpose of these structures is to redirect water flow from the stressed and very often eroded bank to the centre of the channel or other parts of the channel, where the water flow may be used, e.g., for dispersion of unsuitable deposits before its eventual stabilization by natural succession. Another important goal is to achieve a desired change in a stream channel by using the transporting power of the water flow and targeted deposition of any sediment. The area of a deflecting structure, a so-called hydraulic shadow, also appears where sediment is deposited (deflector). The objective is to achieve the deposition of sediments at desired places in the stream. It is possible to design a whole range of suitable or less suitable types of flow deflectors. In our article, we will particularly focus on problems of revitalizing a water course; i.e., the design of structures from biological or biotechnical elements for channel stabilization.

Open access
Molecular analysis of Phytophthora species found in Poland

Abstract

Pathogens of Phytophthora genus are common not only in forest nurseries and stands, but also in water courses. Species of Phytophthora spread with plants for plantings (and soil attached to them) and with water courses as well, attacking the plants growing in riparian ecosystems. Several specialized organisms damaging only one tree species were identified like P. alni on alders or P. quercina on oaks. Some Phytophthora species can develop on several hosts like P. plurivora and P. cactorum on oaks, beeches, alders, ashes and horse chestnuts. Other oomycetes like P. gallica species was found for the first time in Poland in water used for plant watering in forest nursery. Species P. lacustris and P. gonapodyides were found in superficial water. Phytophthora species P. polonica was identified in the declining alder stands for the first time in the world, and P. taxon hungarica and P. megasperma were found in the rhizosphere of seriously damaged ash stands for the first time in Poland. The most often isolated species were P. plurivora (clade 2) with frequency 37% and P. lacustris with frequency 33% (clade 6). The best represented clade 6 revealed the occurrence of 6 species: P. gonapodyides, P. lacustris, P. megasperma, P. sp. raspberry, P. taxon hungarica and P. taxon oak soil.

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Improving Upstream and Downstream Fish Passage at Retis Dam on Hârtibaciu River - Sibiu County (Transylvania)

Abstract

Retis (dam Retis), hydro-technical development like many other transverse hydraulic structures cancel the longitudinal connectivity of Hârtibaciu water course, blocking the migration of different (migrating) species of fish in the river. Also, the lateral connectivity was heavily affected on this water course at a rate of 60%. Therefore, proposing engineering solutions to recover both (lateral and longitudinal) types of connectivity is vital to restore the local ecobiom. The purpose of this article is to establish longitudinal connectivity through an engineering solution that facilitates the fish migration upstream - downstream of Retis dam. This paper proposes an engineered fish passage solution for Retiș Dam on the Hârtibaciu River, using the criteria described in the Water Framework Directive 2000/60/EC document. Anthropogenic barriers located in the Hârtibaciu River disrupt and delay movement of local fish fauna including: Alburnoides bipunctatus (Bloch, 1782), Squalius cephalus (Linnaeus, 1758), Alburnus alburnus (Linnaeus, 1758), Rhodeus amarus (Bloch, 1782), Gobio gobio (Linnaeus, 1758), Romanogobio kessleri (Dybowski, 1862), Barbatula barbatula (Linnaeus, 1758), Barbus meridionalis Risso, 1827 Misgurnus fossilis (Linnaeus, 1758), Cobitis taenia Linnaeus, 1758, Cobitis romanica (Băcescu, 1943), and Cobitis aurata (De Filippi, 1863).

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Changes in a hydrographic network of the Słowiński National Park in terms of photogrammetric analyses

Abstract

The main objective of this study is to evaluate the changes in the hydrographic network of Słowiński National Park. The authors analysed the changes occurring in the drainage network due to limited maintenance in this legally protected natural area. To accomplish this task, elaborations prepared on the basis of aerial photographs were used: an orthophoto map from 1996, hyperspectral imaging from June 2015, and a digital terrain model based on airborne laser scanning (ALS) from June 2015. These spatial data resources enabled the digitisation of the water courses for which selected hydro-morphological features had been defined. As a result of analysing the differences of these features, a quality map was elaborated which was then subjected to interpretation, and the identified changes were quantified in detail.

Open access
The Risk Assessment for a Single Building on the Landslide Areas and Floodplains

Abstract

Mass movements and floods are natural hazards posing a threat to the environment and bring significant economic losses. The flooding and landslide are risks in the municipalities of south-eastern Poland. Long-lasting rains cause initialize process of landslides on the slopes above the river valley, as well as flooding of local infrastructures (buildings, roads, railway tracks) located near water courses. Monitoring of geotechnical and hydrological parameters of the area is the base for the prognosis, as well as the risk assessment associated with them. So, in the paper highlights the issue of the consistency of monitoring and warning systems for these two threats. For landslides work SOPO - System Guards Against Landslides. Hydrogeological bases are defined for floodplains as The Computer System of the National Guard - ISOK. However, notable is the lack of integrity of both systems. In this paper a proposal to determine the overall risk for both threats in case of a single building is presented.

Open access
Automating the creation of channel cross section data from aerial laser scanning and hydrological surveying for modeling flood events / Automatická tvorba geometrie vodních toků na základě syntézy dat z leteckého laserového skenování a hydrologického měření pro modelování povodňových událostí. j. hydrol., hydromech., 60, 2012, 4; 25 lit., 8 obr., 5 tab.

Knowing the extent of inundation areas for individual N-year flood events, the specific flood scenarios, and having an idea about the depths and velocities in the longitudinal or transverse water course profile provided by hydrodynamic models is of key importance for protecting peoples’ lives and mitigating damage to property. Input data for creating the watercourse computational geometry are crucial for hydrodynamic models. Requirements for input data vary with respect to the hydrodynamic model used. One-dimensional (1D) hydrodynamic models in which the computing track is formed by cross-sectional profiles of the channel are characterized by lower requirements for input data. In two-dimensional (2D) hydrodynamic models, a digital terrain model is needed for the entire area studied. Financial requirements of the project increase with regard to the input data and the model used. The increase is mainly due to the high cost of the geodetic surveying of the stream channel. The paper aims at a verification and presentation of the suitability of using hydrological measurements in developing a schematization (geometry) of water courses based on topographic data gained from aerial laser scanning provided by the Czech Office for Surveying, Mapping and Cadastre. Taking into account the hydrological measurement during the schematization of the water course into the hydrodynamic model consists in the derivation of flow rate achieved at the time of data acquisition using the method of aerial laser scanning by means of hydrological analogy and in using the established flow rate values as a basis for deepening of the digital terrain model from aerial laser scanning data. Thus, the given principle helps to capture precisely the remaining part of the channel profile which is not reflected in the digital terrain model prepared by the method of aerial laser scanning and fully correct geometry is achieved for the hydrodynamic model.

Open access