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EN
Meteorological, hydrological, and geomorphological aspects of large floods on the Upper Godavari River were investigated. Synoptic conditions associated with large floods were analyzed to gain an understanding of flood hydrometeorology in the basin. The study reveals that the southwest summer monsoon dominates rainfall in the Upper Godavari Basin (90% of annual rainfall). Moreover, interannual variability was characterized by increased frequency and magnitude of floods primarily after the 1930s and the majority of large floods were connected with low-pressure systems. Unit discharges (Qu) and flash-flood magnitude index (FFMI) were computed to understand the potential for large floods. The high Qu (1.13 and 6.00 m3 s -1 km-2) are likely to be effective in terms of geomorphic changes in the channel. The greater FFMI values (0.27 and 0.56) indicate the flashy and variable nature of floods and the possibility of significant geomorphic work. Parameters of flood hydraulics and hydrodynamics were computed to estimate the efficacy of infrequent and large-magnitude floods. The highest values for unit stream power (5909.61 W m-2) and bed shear stress (609 N m-2) reveal the unusually high capacity of the river to erode and transport coarse sediments. The Froude numbers (>1) confirm extremely erosive supercritical flows. High Reynolds numbers indicate exceedingly turbulent flood discharges, capable of accomplishing a variety of geomorphic activities.
EN
Wetlands represent a small proportion of all habitats. Still, they are very important features within the landscape, particularly in the ecosystem mosaic. They are composed of many specifically adapted organisms. Wetlands spontaneously establish and provide a significant source of heterogeneity and diversity in an urban-industrial landscape. Most of Earth’s wetlands are at risk or have disappeared due to human activity. Apart from natural wetlands, unique anthropogenic wetlands are observed in southern Poland. The aim of study was to assess and analyze the water quality and the spontaneous wetland vegetation which has developed on anthropogenic wetland habitats. The study was conducted on the spontaneous wetland vegetation developed in habitats that emerged due to mineral excavation activities of quarries in the Silesia Upland and Krakow-Częstochowa Upland. The research subjects were wetlands that provide special water chemistry conditions for developing the peat bog vegetation. Water sampling and analyses, vegetation recording, and vegetation numerical analyses were conducted on studied wetlands. The results of a study conducted on flooded post-excavation sites revealed that diverse wetland spontaneous vegetation colonized such habitats. This research showed that anthropogenic wetlands can provide habitats for the development of outstanding biodiversity and form a refuge for calcareous plant species and the subsequently assembled rare peat bog vegetation. The high moisture and the increased presence of magnesium and calcium ions are developing in some sites of the post-mineral excavations. Such habitat conditions in anthropogenic wetlands enhance the occurrence of rare calciphilous species. Maintaining the relevant water conditions is crucial for the protection of these sites. The study presented that, quite frequently, the human-induced transformation results in establishing habitats that provide conditions for refuge organisms, mostly plants crucial for conservation perspective, particularly in the urban-industrial landscape. The additional importance of this study is related to the fact that the area of wetlands decreased. Therefore such anthropogenic wetlands should be integrated into urban planning and industrial site management to enhance biodiversity conservation.
EN
Vast tropical peat swamp forests in Sebangau, Central Kalimantan, Indonesia, make it difficult for officials to fight forest fires. Peat swamp forest fires are recurring events caused by anthropogenic activities around the forest. This research aimed to develop a new canal bulkhead design that prevents blockage of river flow. The approach employed involves enhancing current structures through engineering design in order to decrease the occurrence of structural breakdowns that impede the flow of rivers. The research yielded a new design for a canal bulkhead, featuring an enhanced one-meter-wide sluice gate in a "U" shape, as well as an upgraded boat ladder for passage. The novelty of the present study resides in the design of the canal bulkhead dwelling, which incorporates a ladder, enabling the inhabitants to utilize the canal without obstructing its flow. As a result, there is an enhancement in environmental safety as there are now efficient methods to promptly suppress wildfires.
EN
Nitrogen load is crucial for its application in various fields such as agriculture and improving water quality control for authorities responsible for establishing agricultural policies in the area. The calculation of nitrogen load using existing equations is not applicable for all types of rivers, thus requiring the development of a new equation that can be applied to lakes and rivers in the Biebrza river catchment. To determine the new equation, extensive mapping of the catchment area was conducted, which was adjusted to precipitation and runoff in the area, allowing the observed results to be compared. Based on several analyses, the new equation has better accuracy, RMSE of the new model-based estimation decreased by 65.9% in 2005–2015 and 62.2% in 2016–2021 for river and 92% in 2008–2019 and 95% in 2020–2021 for lakes. Therefore, the application of the new calibrated empirical model provides results close to the real values and it can be used in the Biebrza river basin to simulate the total nitrogen runoff.
EN
One of the main tasks of contemporary hydrology is to plot the best possible rating curve, which has numerous applications in practical hydrological problems. The quality of the curve depends to a significant degree on the precision of hydrometric measurements and the precision in determining the relationship between discharge and the stage (water level). In this study, we engage the multidimensional problem of non-homogeneity of hydrometric data. The distances between a given point of measurement and the given cross-section proved to be highly diverse. Hence, we propose data transformation so that every measurement can be treated as taken in a given cross-section. The transformation allows partial homogenization of measurement data. An automatic non-linear method for estimating the rating curve is also proposed. The method has been tested on selected representatives of mountain, submontane, and lowland rivers of the Oder River catchment basin (Lower Silesia, Poland). Cross-sections selected for analysis were: Łąki on the Barycz River, Lądek Zdrój on the Biała Łądecka River, Jelenia Góra on the Bóbr River, Jakuszyce on the Kamienna River, and Łozy on the Kwisa River.
6
Content available remote Zasady formułowania probabilistycznych modeli deszczów maksymalnych
PL
Zaprezentowane w pracy zasady formułowania probabilistycznych modeli na wysokość deszczów maksymalnych, opracowane na Politechnice Wrocławskiej w latach 2010-2015 [10, 12, 21], po modyfikacjach z 2019 [8] i 2020 roku [9], mogą mieć charakter uniwersalny. Proponowany pięćdziesięcioletni okres pomiarowy, do wyodrębnienia metodą POT niezależnej próby losowej deszczów, jest odpowiedni do wiarygodnej oceny częstości ich występowania od C = 1 rok do C = 50 lat. Do opisu wysokości deszczów maksymalnych, spośród ośmiu możliwych do zastosowania teoretycznych rozkładów prawdopodobieństwa, wskazano na przydatności dwóch rozkładów: Weibulla i GED. Ujednolicenie metodyki tworzenia modeli deszczów maksymalnych w Polsce umożliwi poprawne fizykalnie wzajemne porównywanie ich lokalnych wysokości i da podstawę do szacowania trendów zmian w przyszłości
EN
The principles presented in this paper for formulating heavy rainfall probabilistic models developed at the Wroclaw University of Science and Technology in 2010-2015 [2, 12, 15] after the modifications of 2019 [18] and 2020 [20] can be universal. The proposed 50-year measurement period for extracting an independent random sample of rain using the POT method is suitable for reliably assessing the frequency of occurrence from C = 1 to C = 50 years. To describe the height of the maximum rain, from among eight possible theoretical probability distributions, the usefulness of two distributions was indicated: Weibull and GED. The unification of the methodology for creating models of maximum rain in Poland will enable physically correct mutual comparison of their local heights and provide a basis for estimating trends of change in the future.
EN
This study concerns a Saharan wetland of southern Morocco, the Imlili Sebkha, located south of the Dakhla city. Considered among the rare permanent saharan sebkhas, it is recharged by episodic surface water supplies from an endorheic hydrographic network and by the unconfined aquifer, which emerges permanently through tens of shallow natural cavities. Using satellite data (DEM and rainfall), supplemented by field observations, an analysis of surface water supplies is carried out in this article. Due to the low slopes and the almost generalized silting of the catchment area, most of the rainwater is evaporated or recovered by the phreatic aquifer. Only a small proportion would arrive to the wetland, which would come from the surroundings of the sebkha. Nevertheless, these low inputs can flood a large part of the wetland, including the groundwater cavities, especially during the biggest autumn storms.
PL
Systemy OZE charakteryzują się niestabilna pracą, co wymaga budowy systemów magazynowania energii. Jednym ze sposobów takiego magazynowania są instalacje elektrowni szczytowo pompowych. Wadą takich magazynów jest istotna ingerencja w środowisko naturalne. Likwidacja podziemnych kopalń węgla kamiennego stwarza możliwość budowy podziemnej elektrowni szczytowo pompowej. W artykule przedstawiono rozważania dotyczące budowy instalacji prototypowej UPSH. Analiza zagrożeń na etapie projektu przyczyni się do ograniczenia negatywnych skutków działania inwestycji.
EN
RES systems are characterized by unstable operation, which requires the construction of energy storage systems. One of the methods of such storage are the installations of pumped storage power plants. The disadvantage of such warehouses is a significant interference in the natural environment. Closure of underground hard coal mines makes it possible to build an underground pumped storage power plant. The article presents considerations concerning the construction of a prototype UPSH installation. Risk analysis at the design stage will contribute to limiting the negative effects of the investment.
EN
The distribution of maximum rainfall level is not a homogeneous phenomenon and is often characterised by multimodality and often the phenomenon of the heavy right-hand tail. Modelling this phenomenon using classic probability distributions leads to ignoring multimodality, thus underestimating or overestimating the predicted values in the tail tails – the most important from the point of view of safe dimensioning of drainage systems. To avoid the difficulties mentioned above, a non-parametric kernel estimator method of maximum precipitation density function was used (in the example of rainfall data from a selected station in Poland). The methodology proposed in the paper (for use on any rainfall data from other meteorological stations) will allow the development of more reliable local models of maximum precipitation.
PL
Jak już wspomniano w pierwszej części artykułu, która ukazała się na łamach „Nowoczesnego Budownictwa Inżynieryjnego” w numerze 3 z 2021 r. [1], tematyka dotycząca przepustów wielootworowych jest złożona i wieloaspektowa. Niniejszy artykuł zawiera kolejną część podstawowych informacji związanych z hydrologią i hydrauliką przepustów wielootworowych. Zagadnienia te są specyficzne dla tego typu obiektów, a szczególnie istotne w przypadku omawianych przepustów wielootworowych.
11
Content available Calculation of Bed Load Discharge for Coarse Sand
EN
At present, during the period of intensive climatic changes, it is important to thoroughly take into account the hydrological regimes of water bodies. Оnе of the major conditions of ensuring hydrological safety of territories is а reliable forecast of stream-channel deformations and channel-related processes in the case of water bodies and their separate sections. This paper reviews different methods of calculating bed load discharge. Thus, a new technique оf calculation оf bed load discharge was developed with consideration of the probabilistic estimate оf the beginning оf bed load motion. The method shows satisfactory results compared to previous techniques in use.
EN
Role of the Szalejów Górny flood control dry reservoir on the Bystrzyca Dusznicka River with particular regard to its ability to reduce flood waves
EN
In the eastern Mediterranean region of the Middle East and North Africa, pluvial flooding has become a common and severe climate change consequence event that requires immediate attention. The Wadi-Gaza basin is a critical source of surface water in Palestine; nevertheless, climate change and anthropogenic processes are altering the basin’s hydrological features, resulting in a series of extreme and disastrous flooding events in the coastal plain at the basin downstream. The Mann–Kendall test, Sen’s slope estimator, and the IPTA method that was used to analyze historical rainfall in the basin from 1979 to 2013 refer to a declining trend pattern, which reduces the surge of runoff discharge. Moreover, the future projection for the total monthly rainfall under the ensemble model of CIMP5 for the RCP scenarios of 2.60, 4.50, and 8.50 demonstrate a general decreasing trend in the rainfall with a variation ranging between about − 36 and − 53%. The frequency analysis for the maximum daily rainfall using different computing approaches shows that the theoretical maximum rainfall values for the assessment of flooding events were assigned to 22, 31, 35, 45 52, 59, 66, and 77 mm for the whole basin for the return periods (T) of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively. The land cover–land use of the basin shows that 51% is barren land while the other portion is divided between urban (~16%), agricultural (~ 13%), and natural (~ 20%) lands. However, the type of soil that covers the basin is classified mainly as clay, loam, and sandy clay. According to the hydraulic analysis of downstream flooding, the volume of surge water that might reach the coastal plain in the event of water storms of 22 and 77 mm is around 6 and 118 million cubic meters, respectively. The area at risk of inundation due to foods in the Wadi-Gaza is between 3 and 17 km2 , covering around 5–29 percent of the Gaza Strip’s middle governorate area, respectively.
EN
The 2150 km2 transboundary Gurara Reservoir Catchment in Nigeria was modelled using the Water Evaluation and Planning tool to assess the hydro-climatic variability resulting from climate change and human-induced activities from 1989 to 2019 and projected to the future till 2050. Specifically, the model simulated the historic data set and predicted the future runoff. The initial results revealed that monthly calibration/validation of the model yielded acceptable results with Nash–Sutcliff efficiency (NSE), percent bias (PBIAS), and coefficient of determination (R2) values of 0.72/0.69, 0.72/0.67 and 4.0%/1.0% respectively. Uncertainty was moderately adequate as the model enveloped about 70% of the observed runoff. Future predicted runoffs were modelled for climate ensembles under three different representative concentration pathways (RCP4.5, RCP6.5 and RCP8.5). The RCP projections for all the climate change scenarios showed increasing runoff trends. The model proved efficient in determining the hydrological response of the catchment to potential impacts from climate change and human-induced activities. The model has the potential to be used for further analysis to aid effective water resources planning and management at catchment scale.
EN
This study aims to investigate how grazing is perceived across the Curvature Subcarpathians (Romania) by farmers. We investigate farmers’ attitudes toward and understanding of grazing practice and associated processes involving small ruminants (sheep and goats). Additionally, we review the scientific literature and new discussions about grazing vs overgrazing terms and changes in the Romanian small ruminant livestock. Results of the survey on the total of 101 case studies from villages in 3 counties (Damboviţa, Buzau, and Vrancea) show that: (i) grazing is differently perceived; (ii) most of the areas designated for grazing are located near riverbanks (over 55%); most of the respondents reported that the areas intended for grazing are quite close to the inhabited areas; distances are less than 2.5 km; and over 60% of respondents believe that the areas are continuously subject to soil degradation processes; (iii) answers given in connection with the issues addressed provide both relevance to the Curvature Subcarpathians (6792 km2 ) and the potential impact of higher pressure of grazing on local areas due to the discouragement of specific transhumance policies (more than 60% required subsidies). The average stocking density is about 4.7 head per ha. In general, beyond different farmers’ perceptions, a scientific question remains open regarding the quantitative impact of grazing on hydrological processes. Hence, a field survey (e.g., rainfall-runoff experiments) to assess grazing pressure on water and soil resources will be performed.
EN
Currently, due to reduced water resources, there is a need to build reservoirs in Poland. Reservoirs perform important economic, natural and recreational functions in the environment, improve water balance and contribute to flood protection. In the construction of reservoirs, it is necessary to consider not only hydrological issues related to water quantity, but also its quality, silting, and many other factors. Therefore, the physiographic, hydrological, hydrochemical, and hydrogeological conditions of the projected reservoirs have to be taken into account to limit the potential negative effects of decisions to build them. In order to assess the suitability of eight projected small water retention reservoirs (to increase water resources in the Barycz River catchment in Lower Silesia and Greater Poland provinces, this article takes into account hydrological indicators (efficiency of the reservoir, operation time, dependence on the intensity of silting, and flood hazard indicator), water quality (phosphorus load and nitrogen load), hydrogeological conditions (type of geological substratum for the reservoir basin and filtration losses), and safety of the reservoir dam. To develop a theoretical model describing the regularities between the indicators, multivariate statistical techniques were used, including the Principal Component Analysis (PCA) and the Factor Analysis (FA). In order to assess the reservoirs, a synthetic indicator was developed to compare the reservoirs with each other in relation to the conditions. The Cluster Analysis (CA) was used for typological classification of homogeneous locations of projected small retention reservoirs. Own research procedure for identification of the most advantageous water reservoirs, with the use of multivariate statistical techniques, may be used as a tool supporting decision making in other facilities intended for implementation in provincial projects of small retention.
PL
Obecnie w Polsce z powodu zmniejszonych zasobów wodnych istnieje potrzeba budowy zbiorników wodnych. Pełnią one w środowisku ważne funkcje gospodarcze, przyrodnicze, rekreacyjne, poprawiają bilans wodny i przyczyniają się do ochrony przeciwpowodziowej. Budując zbiornik wodny, oprócz zagadnień hydrologicznych związanych z ilością wody, należy wziąć pod uwagę jakość wody, która będzie retencjonowana w zbiorniku, jego zamulenie oraz szereg innych aspektów. Bardzo ważna jest więc analiza uwarunkowań zbiorników planowanych, w tym fizjograficznych, hydrologicznych, hydrochemicznych i hydrogeologicznych, aby ograniczyć potencjalne negatywne skutki podejmowania decyzji o budowie takich obiektów. W celu oceny możliwości realizacji ośmiu planowanych zbiorników małej retencji wodnej w kontekście potrzeby zwiększania zasobów wodnych na obszarze zlewni Barycz w województwie dolnośląskim i wielkopolskim w niniejszym artykule uwzględniono wskaźniki hydrologiczne (sprawność zbiornika, czas eksploatacji ze względu na intensywność zamulania, wskaźnik potencjalnego zagrożenia powodzią), jakości wody (obciążenie ładunkiem fosforu i azotu), hydrogeologiczne (rodzaj podłoża geologicznego pod czaszę zbiornika wodnego i straty filtracyjne) oraz bezpieczeństwa zapory zbiornika. Do opracowania teoretycznego modelu, opisującego prawidłowości zachodzące pomiędzy tymi wskaźnikami, wykorzystano wielowymiarowe techniki statystyczne takie jak: Principal Component Analysis (PCA) i Factor Analysis (FA). W celu oceny planowanych zbiorników w aspekcie najbardziej korzystnych do realizacji opracowano syntetyczny wskaźnik, który umożliwił porównanie tych zbiorników w odniesieniu do rozpatrywanych uwarunkowań. Wykonano również z zastosowaniem Cluster Analysis (CA) typologiczną klasyfikację planowanych zbiorników małej retencji wodnej pod względem jednorodnych lokalizacji na analizowanym obszarze. Zaproponowana w niniejszej pracy autorska procedura badawcza identyfikacji najkorzystniejszych, spośród planowanych do realizacji, zbiorników wodnych z zastosowaniem wielowymiarowych technik statystycznych, może posłużyć jako narzędzie wspomagające podejmowanie decyzji przy innych obiektach planowanych do realizacji w wojewódzkich planach rozwoju małej retencji.
EN
The data analysed in the paper are related to the hydrology of tidal waters at a tidewater glacier terminus. Set of data was collected in the wide span of time from 2009 till 2015 in the Nordaustlandet and Southwest Spitsbergen near various tidal glaciers terminus. The data are related to tidal phenomenon, calving glacier, drifting ice, hydrology of brackish water from ice of glacial origin and theirs consequences on safety of navigation. Thus, results of analysis of hydrological data may serve for improvement of safety of maritime transport in polar regions on high latitudes in vicinity of tidewater glaciers. The research work was part of the reconnaissance of hydrological and hydrographic conditions for the needs of other studies. Measurements were taken at the Kamavika inlet leading from the Hans Glacier to-wards Hornsund fjord (Southern Svalbard). Based on above data, the causes of disturbances and errors of hydrographic measurements that may occur in area of occurrence of brackish water layer and their influence on errors of digital information displayed in ECDIS systems as well as prediction of ice conditions and safety of watercrafts in vicinity of glacier terminus and on anchorage were described.
EN
In northern Iraq, countless non-abuse stream valleys can be used to store water for a variety of purposes; domestic, supplementary irrigation, and recharging groundwater. Bandawaya is one of the stream valleys, which form the first perspective has excellent quality. The location of the suggested dam has been evaluated by hydrological and geotechnical studies. Geotechnical studies included measurement of all the parameters related to the rock mass classification for evaluation based on four classification systems, which are the Q-System, the rock mass rating (RMR), the geological strength index (GSI), and the rock mass index (RMi). The classification results indicated that the rocks of the valley are good for constructing a dam on them, with some weak zones that may affect the integrity of the dam, which the study recommended treating before starting the construction of the dam. According to preliminary studies on different dam’s heights the qualification demonstrates an excellent choice of the site. Four stream orders are recognized, dendritic pattern in the southern part of the watershed, and trellised in the northern part. Three heights assumed to the proposed dam 450, 460, 470 m a.s.l. with 640,764; 3429,787; 8,590,763 m3 storage capacity respectively. According to the Q-System, the RMR, the GSI, and the RMi, the rock mass of the study area is evaluated. The findings illustrate the excellent selection by geotechnical, hydrological, and engineering features of the dam place.
EN
This article is an analysis of how the World Meteorological Organization (WMO) constituent bodies governance reform (WMO Reform) can affect the activities of the Polish National Hydrological and Meteorological Service. The analysis employs the SWOT (Strengths, Weaknesses, Opportunities, Threats) model. The World Meteorological Congress is the highest authority of the World Meteorological Organization, whose findings guide the operations of the WMO and the National Meteorological and Hydrological Services (NMHSs) globally. During the 18th Congress, in June 2019, discussions covered the routine operations of the WMO and its Secretariat, the status and development prospects of all the Organization's research and technical programs, and the Organization's budget for the 18th financial period beginning in 2020. The key actions of the Congress, however, were the election of the WMO senior officers and final approval (after thorough discussion) of the WMO Reform of its governance structure. The purpose of the Reform is to ensure better preparation of the organization for the challenges of the present and future, such as climate change and its impact, the growing number and intensity of extreme weather events, environmental degradation, and increasing urbanization. The tasks of the National Hydrological and Meteorological Service in Poland are performed by the Institute of Meteorology and Water Management - National Research Institute (IMGW-PIB), in accordance with the provisions of the Water Law.
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