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Tytuł:
Impact of the ban on illegal mining activities on raw water quality: a case-study of Konongo Water Treatment Plant, Ashanti Region of Ghana
Autorzy:
Anyame, Bawa Sadique
Antwi-Agyei, Prince
Domfeh, Martin Kyereh
Powiązania:
https://bibliotekanauki.pl/articles/2201399.pdf
Data publikacji:
2022
Wydawca:
Główny Instytut Górnictwa
Tematy:
galamsey
illegal mining
water quality
Mann-Kendall test
Konongo Water Treatment Plant
Anuru River
nielegalne wydobycie
jakość wody
test Manna-Kendalla
stacja uzdatniania wody Konongo
rzeka Anuru
Opis:
The Government of Ghana prohibited Artisanal and Small-Scale Mining (ASM) operations from 2017 to 2018 as part of its strategy to address the socio-environmental issues caused by illegal mining activities, also referred to as “galamsey” operations. This study assessed the trend in the water quality of raw water abstracted at the Konongo Water Treatment Plant (WTP) for treatment before and after implementing the ban on “galamsey” operations. The main source of raw water for the Konongo WTP is the Anuru River. Secondary data on physicochemical water quality from 2006 to 2019 was sourced from the Konongo WTP and the Ashanti Regional Water Quality Assurance Unit of Ghana Water Company Limited (GWCL). Mann-Kendall seasonality test was used to determine trends in the water quality data using XLSTAT statistical tool. The results showed a statistically significant (5% level of significance) upward trend in colour, turbidity, temperature, total iron, and sulphate before the ban on “galamsey” activities. There was statistically significant evidence of a downward trend in total hardness, calcium hardness, turbidity, total alkalinity, and chloride after the ban on “galamsey” operations.
Źródło:
Journal of Sustainable Mining; 2022, 21, 2; 80--92
2300-1364
2300-3960
Pojawia się w:
Journal of Sustainable Mining
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analyzing trends in reference evapotranspiration in Northwest part of Iran
Autorzy:
Azizzadeh, M.
Javan, K.
Powiązania:
https://bibliotekanauki.pl/articles/124913.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
reference evapotranspiration
trend
Mann-Kendall test
Sen’s estimator
northwest of Iran
Opis:
Evapotranspiration is one of the most important components of the hydrological cycle. It is essential in all of hydro climatological studies, irrigation and drainage calculations, water balance, and crop water requirements. The aim of this study is to investigate temporal trends of reference evapotranspiration (ETo) in the Northwest part of Iran. For this purpose, the meteorological data from 20 synoptic stations over a 22-year time period (1986–2007) were used. After the calculation of ETo using the Penman-Monteith FAO-56 method, the non-parametric Mann-Kendall test was used to investigate the temporal trends on monthly, seasonal and annual scales. The Sen’s estimator method was used and to calculate the slope of the trend line. The results indicated that the ETo trend was increasing (positive) in various months, except for the Sarab station in December. On a monthly scale, the Maragheh station showed the highest positive slope in August, and the Bijar station showed the highest negative slope in May. 43.34% of the stations showed a significant trend, and 56.66% did not show a significant trend. In seasonal and annual time periods there was not a significant decreasing trend in any of the stations. The analysis of the results shows that in the spring 20%, in the summer 55%, in the fall 70%, in the winter 75%, and on an annual scale 60% of the stations under study showed an increasing trend. For modeling these changes, the spatial distribution of ETo trends (on monthly, seasonal, and annual scales) were mapped in ArcGIS. Final models determine that most stations in this study show an increasing trend on monthly, seasonal and annual scales.
Źródło:
Journal of Ecological Engineering; 2015, 16, 2; 1-12
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of climate fluctuations on the spring runoff regime with regard to rivers in Lithuania
Wpływ zmian klimatycznych na reżim wiosennego odpływu na przykładzie rzek Litwy
Autorzy:
Bagdžiūnaitė-Litvinaitienė, L.
Litvinaitis, A.
Powiązania:
https://bibliotekanauki.pl/articles/293070.pdf
Data publikacji:
2015
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
climate change
Mann-Kendall test
river
runoff regime
trend
reżim przepływu
rzeka
test Manna–Kendalla
zmiany klimatyczne
Opis:
The article describes the impact of fluctuations in climatic factors on hydrological processes. The analysis of climate and hydrology covers two periods, the first up to 1996 and the second from 1981 to 2012. Study object includes 22 river basins situated on the eastern coast of the Baltic Sea: 1000 km2, up to 10 000 km2 and bigger. The study involved Mann–Kendall, Spearman's and linear regression tests. Causal relationships, as criteria that may fundamentally change the runoff regime set up by climatic factors, were established by evaluating the size of the river basin and assessing the spread of sediments, lakes, swamps and forests in the river basin. The analysis of data from the last thirty years disclosed that, with reference to the previously obtained information, floods in lakes became substantially reduced. Nevertheless, within the winter period of recent years, temperatures prevented lakes from acting as water reservoirs. The paper examined and defined the impact of sediments on variations in the runoff regime. For the period of the last thirty years, cut-off dates, i.e. flood start, crest and end, have advanced.
Przedmiotem artykułu jest wpływ czynników klimatycznych na zmianę procesów hydrologicznych. Dokonano analizy klimatycznej i hydrologicznej dwóch okresów: do roku 1996 i od roku 1981 do 2012. Obiektem badań były zlewnie 22 rzek we wschodniej części wybrzeża Morza Bałtyckiego: do 1000 km2, do 10 000 km2 i większe. W badaniach stosowano testy statystyczne Manna–Kendalla, Spearmana i regresji liniowej przeznaczone do ustalenia związku przyczynowego w ocenie wielkości zlewni rzeki, osadów, jezior, bagien, zalesienia w zlewni rzeki jako kryteria, które w zasadniczy sposób mogą zmienić reżim odpływu ukształtowany przez czynniki klimatyczne. Analiza danych pochodzących z ostatnich trzydziestu lat wykazała, że według wcześniejszych danych jeziora w większym stopniu ograniczały występowanie powodzi, jednak w ostatnich latach temperatura w sezonie zimowym nie pozwala jeziorom pełnić funkcji akumulatorów wodnych. Zanalizowano i określono wpływ osadów na zmiany reżimu przepływu. Stwierdzono, że w ciągu ostatnich trzydziestu lat graniczne daty powodzi – początek, szczyt i koniec – notowane są wcześniej.
Źródło:
Journal of Water and Land Development; 2015, 25; 23-30
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamika występowania niżówek w rzekach górskich i wyżynnych na przykładzie Wisłoki i górnego Wieprza. Cz. 2. Zmienność wieloletnia
Dynamics of low flows in mountain and upland rivers on example of Wisłoka and upper Wieprz rivers. P. 2. Multi-annual variability
Autorzy:
Baran-Gurgul, K.
Raczyński, K.
Powiązania:
https://bibliotekanauki.pl/articles/338805.pdf
Data publikacji:
2017
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
autokorelacja
czas trwania niżówki
deficyt niżówki
metoda Pit Under Threshold
niżówka
test Manna–Kendalla
autocorrelation
low flow
low flow deficit
low flow duration
Mann–Kendall test
Pit Under Threshold
Opis:
Celem niniejszej pracy jest ocena częstości występowania niżówek w rzekach położonych w otoczeniu środowiska przyrodniczego o różnym charakterze – w rzece górskiej, tj. Wisłoce i jej dopływach, i w rzece wyżynnej, tj. górnym Wieprzu wraz z dopływami. Analizę dynamiki pojawiania się przepływów niżówkowych wykonano na podstawie zmienności podstawowych charakterystyk niżówek (tj. czasu trwania i objętości niżówki) w wieloleciu 1983–2013. W rozpatrywanym okresie zaobserwowano więcej niżówek w rzekach górskich niż wyżynnych, lecz były one krótsze. W rzekach wyżynnych stwierdzono więcej lat „bezniżówkowych”. Badanie stacjonarności rocznych szeregów charakterystyk niżówek wykonano z użyciem testu Shapiro–Wilka, Ljunga–Boxa i Manna–Kendalla z poprawką na autokorelację. Około połowy analizowanych szeregów nie spełniało warunku normalności. Do badania trendu wykorzystano test Manna–Kendalla. Test ten wykazał trend malejący badanych ciągów w prawie wszystkich przekrojach w rzekach wyżynnych i tylko w jednym – w rzekach górskich. W około połowie ciągów stwierdzono istotną, potwierdzoną testem Ljunga–Boxa, autokorelację rzędu pierwszego – zarówno w szeregach czasów trwania, jak i objętości niżówek. Stwierdzono, że w badanych ciągach występują dwa typy funkcji autokorelacji. Pierwszy typ funkcji, występujący głównie w rzekach wyżynnych, cechuje się dłuższą pamięcią, okresy podobne trwają około 10–11 lat. W pozostałych przypadkach ACF wskazują na pamięć krótszą i odnoszą się do rzek o większej dynamice przepływów.
The main goal of this study is to assess the long-term dynamics of low flows occurrence in catchments located in different environment conditions: mountain river: Wisłoka and its tributaries and upland river: Upper Wieprz with tributaries. Analysis of low flows occurrence was based on variability of basic low flow characteristics (duration time and volume of low flow episode) in period 1983–2013. In studied period, more low flows occurred in mountain rivers, however the time of duration was shorter than in upland area. On uplands, more years without low flow episodes were observed. For stationary of annual series analysis Shapiro–Wilk, Ljung–Box and Mann–Kendall tests with autocorrelation correction were used. About half of studied series does not complete the terms of normal distribution. For this reason, trend studies were performed by using nonparametric tests. Mann–Kendal test showed descending trends in almost all gauging sections located in upland region and only in one located in mountain rivers. In half of series there was a significant, confirmed by Ljung–Box test, first rank autocorrelation – in both duration time and volume series. It was found that in tested series, there were two types of autocorrelation function. First type of function, that occurred mainly in upland area, was characterized by long-term memory, where similar periods last for about 10–11 years. In other cases, ACF indicated a short memory of episodes and occurred in catchments with higher flow dynamics.
Źródło:
Woda-Środowisko-Obszary Wiejskie; 2017, 17, 1; 5-17
1642-8145
Pojawia się w:
Woda-Środowisko-Obszary Wiejskie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Short-Term and Seasonal Trend Detection of Sediment Discharges in Turkish Rivers
Autorzy:
Burgan, Halil Ibrahim
Powiązania:
https://bibliotekanauki.pl/articles/2174920.pdf
Data publikacji:
2022
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
innovative trend analysis
ITA
Mann-Kendall test
seasonal Mann-Kendall test
sediment discharge
trend
Turkish rivers
Opis:
Hydrometeorological variables are tested by trend methods to detect trends in river basins. Mann-Kendall and Spearman’s rho tests are widely used as traditional trend methods. Besides, some new trend tests are applied to hydrometeorological variables, such as Innovative Trend Analysis (ITA). Sediment discharge observations are more complicated than other hydrometeorological variables. In general, sediment data are observed on a monthly time scale. Therefore, there are minimal studies on sediment data, especially in Turkey. In this study, Innovative Trend Analysis (ITA), Mann-Kendall, Correlated Mann-Kendall and Seasonal Mann-Kendall trend analyses are applied to sediment discharges in Turkish river basins. According to Mann-Kendall, Correlated Mann-Kendall and Seasonal Mann-Kendall results, positive trends have detected only 8, 2 and 20 gauging stations, respectively. Then, 30 positive and 15 negative trends were detected by ITA methodology. The trend slopes calculated from ITA methodology are categorised because some positive and negative trends are weak. The applied trend methods are evaluated together, considering the climate properties of hydrological regions in Turkey. Increasing trends in sediment data are detected from the rivers in the Mediterranean region of Turkey. The results of the study would help to manage water resources as well as sustainable development in the Turkish river basins.
Źródło:
Rocznik Ochrona Środowiska; 2022, 24; 214--230
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Water Quality Trends of the Tisa River Along its Flow Through Serbia
Trendy zmian jakości wody rzeki Tisa wzdłuż jej biegu przez Serbię
Autorzy:
Dundjerski, J. J.
Savic, R.
Grabic, J.
Blagojevic, B.
Powiązania:
https://bibliotekanauki.pl/articles/1813916.pdf
Data publikacji:
2017
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
water quality
pollution
trend
Mann-Kendall test
self-purification
jakość wody
zanieczyszczenie
test Manna-Kendalla
samooczyszczanie
Opis:
The problem of the paper is water quality of the water body Tisa which geographically belongs to Serbia. The scope of the analyses are water quality monitoring data of the Tisa River at tree measuring points along its flow through Serbia: Martonos, Novi Becej and Titel in period 2004-2014. The analyses encompassed conductivity, dissolved oxygen, BOD5, COD, nitrates and total phosphorus. Assessment of water quality has been conducted by the application of contemporary classifications and criteria of the Republic of Serbia. Reference conditions for achieving excellent ecological status, I class of water quality are achieved for conductivity, dissolved oxygen, along investigated section (measuring points: Martonos, Novi Becej and Titel) and BOD5 at the measuring point Martonos. Downstream at measuring points Novi Becej and Titel for BOD5 water quality belongs to class II. According to concentrations of COD, nitrates and total phosphorus water quality belongs exclusively to class II. Linear regression analyses was applied for determining trend lines of parameters, while Mann-Kendell test in most cases (14/18), i.e. 78%, has confirmed nonexistence of significant trend. Water quality during the past decade is stable. A statistically significant trend was confirmed in 4 cases: nitrates (measuring point Martonos, descending trend), BOD5 and total phosphorus (measuring point Novi Becej, descending trend), and dissolved oxygen (measuring point Titel, increasing trend). Signs of these trends speak in favor of future improvement of water quality of the Tisa River in Serbia.
W artykule opisano jakość wody w rzece Tisa, która geograficznie należy do Serbii. Zakres analiz obejmuje są dane dotyczące jakości wody w rzece Tisa w punktach pomiarowych wzdłuż biegu przez Serbię: Martonos, Novi Becej i Titel w latach 2004-2014. Analizą objęto: przewodnictwo, tlen rozpuszczony, BZT5, ChZT, azotany i fosfor ogólny. Ocena jakości wody została przeprowadzona przez zastosowanie aktualnej klasyfikacji i kryteriów w Republice Serbii. Warunki parametrów odpowiadające doskonałemu stanowi ekologicznemu, I klasy jakości wody, osiągnięto dla przewodności, tlenu rozpuszczonego, wzdłuż całego badanego odcinka (punkty pomiarowe: Martonos, Novi Becej i Titel) oraz BZT5, w punkcie pomiarowym Martonos. W dolnym biegu rzeki, w punktach pomiarowych Novi Becej i Titel dla BZT5 wody należą do klasy II. Jeśli chodzi o ChZT, azotany i fosfor całkowity jakość wody należy do klasy II. W celu określenia linii trendu parametrów zastosowano analizę regresji liniowej, a test Manna-Kendalla, w większości przypadków (14/18), tj. 78%, potwierdził brak znaczącego trendu. Jakość wody w ciągu ostatnich dziesięciu lat jest stabilna. W 4 przypadkach stwierdzono statystycznie istotną tendencję: azotany (punkt pomiarowy Martonos, tendencja spadkowa), BZT5 i fosfor ogólny (punkt pomiarowy Novi Becej, tendencja spadkowa) oraz tlen rozpuszczony (punkt pomiarowy Titel, tendencja wzrostowa). Trendy mogą oznaczać poprawą jakości wody rzeki Tisa w Serbii w przyszłości.
Źródło:
Rocznik Ochrona Środowiska; 2017, Tom 19; 17-35
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of a small storage reservoir on the hydro-chemical regime of a flysch stream : A case study for the Korzeń stream (Poland)
Autorzy:
Fudała, Wioletta
Bogdał, Andrzej
Kowalik, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/28411650.pdf
Data publikacji:
2023
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Mann-Kendall test
physical indicators
chemical indicators
storage reservoir
surface water
trend of changes
tendency of changes
Opis:
The paper presents in form of a case study the results of 10-year long hydro-chemical studies on the Korzeń stream on which the “Skrzyszów” small storage reservoir was built. Studies aimed at evaluating the impact of the reservoir on the surface water quality in a Flysch stream. The basis for the analysis was results of 21 hydro-chemical water quality parameters, from the following groups of indicators: physical and acidity, oxygen and organic pollution, biogenic, salinity, metals. Indicators were determined in one-month intervals in two periods: 2005-2009 (before the reservoir was built) and 2015–2019 (after the reservoir was built). Obtained results were subjected to a statistical analysis. The trend analysis of changes was performed using the Mann-Kendall test or the seasonal Kendall test; significance of differences between indicator values from two periods was evaluated using the nonparametric Mann-Whitney U test. Results of analysis showed significant change trends of water quality parameters, in case of total iron concentration the trend was downward in both periods. Statistically significant differences between the values of definite majority of indicators were found in two analysed periods, indicating both favourable and unfavourable impact of the reservoir on water quality in the stream. Construction of the storage reservoir resulted in a significant change of physical and chemical indicators of water flowing in the stream. Random variation dynamics as well as tendencies and trends of changes over time have changed. In addition to modifying the stream hydro-chemical regime, the reservoir also affected the social and natural conditions.
Źródło:
Journal of Water and Land Development; 2023, 59; 13--24
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of climate change on rice production at Khulna District, Bangladesh
Autorzy:
Hossain, N.
Saifullah, A.S.M.
Bhuiyan, S.H.
Uddin, N.
Rahman, M.
Powiązania:
https://bibliotekanauki.pl/articles/2049750.pdf
Data publikacji:
2019
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
rice
production
climate change
trend analysis
Bangladesh
gross domestic product
Mann-Kendall (MK) test
Rice Production
Opis:
In Bangladesh 164 million people depend on rice but due to climate change (CC) vulnerabilities the yield of rice is severely reducing. Therefore, this study aimed to explore the effects of CC on rice yield using recent trend analysis, Mann-Kendall (MK) trend test and correlation. For this study, the required climate and selected rice production data were collected from Bangladesh Meteorological Department (BMD) and Department of Agriculture Extension (DAE), Khulna. In time series statistics both parametric and nonparametric methods were applied to detect a monotonic trend of climatic variability and Aman rice production. Correlation between climatic variability and rice production was also investigated. The study exposed that the temperature and rainfall had an increasing trend and statistically significant whereas the relative humidity found decreasing. Overall, the bright Sunshine had positive trend but week. According to nonparametric trend test of climatic variability and Aman yield only minimum temperature showed a positive trend which found statistically significant. In contrast, Mann-Kendall trend test revealed that rainfall had positively significant while temperature had negative significant. The correlation revealed the Aman production is a strong response with minimum temperature whereas the Lona Coche showed a positive correlation with maximum temperature. The variation of Aman production exhibited a positive correlation with both Rainfall and humidity respectively and Lona Coche found a negative correlation. The sunshine had a week correlation against both yields. The findings suggest should give attention of temperature-tolerant rice varieties to mitigate possible adverse effects of CC.
Źródło:
Environment, Earth and Ecology; 2019, 3, 1; 42-54
2543-9774
2451-4225
Pojawia się w:
Environment, Earth and Ecology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of distribution of precipitation duration and amounts in Legnica in the period of 1966–2015
Analiza rozkładów długości trwania i wielkości opadów w Legnicy w latach 1966–2015
Autorzy:
Jakubczyk, Teresa
Powiązania:
https://bibliotekanauki.pl/articles/293381.pdf
Data publikacji:
2019
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
analysis of distributions
Mann–Kendall test
precipitation
rainfall conditions
rainfall variability
analiza rozkładów
opady
test Manna-Kendalla
warunki opadowe
zmienność opadów
Opis:
The paper presents the results of analysis of duration of precipitation sequences and the amounts of precipitation in individual sequences in Legnica. The study was aimed at an analysis of potential trends and regularities in atmospheric precipitations over the period of 1966–2015. On their basis a prediction attempt was made for trends in subsequent years. The analysis was made by fitting data to suitable distributions – the Weibull distribution for diurnal sums in sequences and the Pascal distribution for sequence durations, and then by analysing the variation of the particular indices such the mean value, variance and quartiles. The analysis was performed for five six-week periods in a year, from spring to late autumn, analysed in consecutive five-year periods. The trends of the analysed indices, observed over the fifty-year period, are not statistically significant, which indicates stability of precipitation conditions over the last half-century.
W pracy przedstawiono wyniki analiz rozkładów długości trwania sekwencji opadowych oraz wielkości opadów w poszczególnych sekwencjach w Legnicy. Badania miały na celu przeprowadzenie analizy ewentualnych tendencji i regularności w opadach atmosferycznych w okresie 1966–2015. Na ich podstawie podjęto próbę predykcji dla tendencji w kolejnych latach. Analizę wykonano przez dopasowanie do danych odpowiednich rozkładów – rozkładu Weibulla do sum dobowych w sekwencjach oraz rozkładu Pascala do długości sekwencji, a następnie przez zbadanie zmienności poszczególnych wskaźników, takich jak średnia, wariancja i kwartyle. Analiza została przeprowadzona w odniesieniu do pięciu sześciotygodniowych okresów w ciągu roku od wczesnej wiosny do późnej jesieni, rozpatrywanych w kolejnych pięcioleciach. Tendencje badanych wskaźników zaobserwowane na przestrzeni pięćdziesięciolecia nie są istotne statystycznie, co świadczy o stabilności zjawiska opadów w ostatnim pięćdziesięcioleciu.
Źródło:
Journal of Water and Land Development; 2019, 41; 69-76
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the long-term variability of temperature trends and changes in surface air temperature in Kolkata Weather Observatory, West Bengal, India
Autorzy:
Khan, A.
Chatterjee, S.
Bisai, D.
Powiązania:
https://bibliotekanauki.pl/articles/108500.pdf
Data publikacji:
2015
Wydawca:
Instytut Meteorologii i Gospodarki Wodnej - Państwowy Instytut Badawczy
Tematy:
temperature
trend analysis
Mann-Kendall test
Sen’s slope estimator
Kolkata
Opis:
The impact of climate change on annual air temperature has received a great deal of attention from climatologists worldwide. Many studies have been conducted to illustrate that changes in temperature are becoming evident on a global scale. Air temperature, one of the most important components of climate parameters, has been widely measured as a starting point towards the apprehension of climate change and variability. The main objective of this study is to analyse the temporal variability of mean monthly temperature for the period of 1941 to 2010 (70 years). To detect the magnitude of trend in mean monthly temperature time series, we have used non-parametric test methods such as The Mann-Kendall test, often combined with the Theil-Sen’s robust estimate of linear trend. Whatever test is used, the user should understand the underlying assumptions of both the technique used to generate the estimates of a trend and the statistical methods used for testing. The results of this analysis reveal that four months – January, February, March and December – indicate a decreasing trend in average temperature, while the remaining eight months have an increasing trend. The magnitude of Mann-Kendall trend statistic Zc for this declining temperature and the magnitude of slope for the months of January, February and December are confirmed at the high significance levels of α = 0.001, 0.01 and 0.1 respectively. Though, the overall trend is positive for monthly as well as seasonally efficient time series.
Źródło:
Meteorology Hydrology and Water Management. Research and Operational Applications; 2015, 3, 2; 9-16
2299-3835
2353-5652
Pojawia się w:
Meteorology Hydrology and Water Management. Research and Operational Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trend analysis of changes in soil moisture from the different depths in the Martew Forestry
Autorzy:
Krysztofiak-Kaniewska, A
Miler, A. T.
Urbaniak, M.
Ziemblińska, K.
Wróbel, M.
Powiązania:
https://bibliotekanauki.pl/articles/101526.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
Mann-Kendall test
soil moisture
Martew Forestry
Opis:
The paper presents trends in average annual soil moisture in the area covered by the sixty-year old pine stand. The area of analysis is located in the Tuczno Forest District, the Martew Forestry, in the north-western part of Poland. The calculations were based on the measurements of soil moisture at seven different depths below the ground level. A set of probes was installed for measuring the moisture using TDR method in order to calculate retention changes in the unsaturated zone. Humidity measurements used in this work were carried out at daily intervals throughout the year 2014. Designated trends were analysed using the non-parametric Mann – Kendall test, which is used for detecting trend of hydrological and meteorological parameters. Negative values of the Mann-Kendall statistics point to a declining trend for most – six out of the seven, analysed levels of measurement. The tendency toward dryness was not confirmed by the data set of precipitations. Although precipitations are considered to be the main driver of variations in soil moisture their impact severity seems to be controlled by other characteristics of the catchment area and components of the water balance, such as evapotranspiration.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2016, IV/1; 1157-1167
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Local Precipitation Trends in the Podkarpackie and Lubuskie Voivodeships
Autorzy:
Kubiszyn, Katarzyna
Powiązania:
https://bibliotekanauki.pl/articles/27314853.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
precipitation local
Mann-Kendall test
precipitation map
drainage system
erosion processes
landslide prevention
Podkarpackie Voivodeship
Lubuskie Voivodeship
opady lokalne
Test Manna-Kendalla
mapa opadów
system odwadniający
procesy erozyjne
zapobieganie osuwiskom
województwo podkarpackie
województwo lubuskie
Opis:
The type of precipitation is one of the factors taken into consideration when deciding on the most optimal drainage system. Drainage systems are used to prevent the landslides caused by water erosion. Rainfall affect the rate of infiltration and the intensity of surface runoff and thus the occurrence, course and effectiveness of erosion processes [1, 2, 3]. Knowledge of local precipitation trends will help to apply precautions and thus minimise the risk of adverse events such as landslides. What is more it can help more effectively manage projects risks and costs. The aim of this study was to analyse more than 30 years of data from daily rainfall measurements from the Podkarpackie Voivodeship and to check whether the occurrence of precipitation is a random event or whether it indicates long-term trends that may affect changes in ground stability. The non-parametric Mann-Kendall test and correlation test were used for the analysis.
Źródło:
Civil and Environmental Engineering Reports; 2023, 33, 1; 122--138
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Do Changes of Rainfall Trends Affect Choice of Drainage Systems?
Autorzy:
Kubiszyn, Katarzyna
Łochańska, Dorota
Powiązania:
https://bibliotekanauki.pl/articles/27314845.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
precipitation trends
local precipitations
Mann-Kendall test
slope stability
dewatering systems
decision-making process map
opady lokalne
trendy opadów
test Manna-Kendalla
stateczność zboczy
systemy odwadniania
mapa procesu decyzyjnego
Opis:
Precipitation is one of the main factors causing surface, linear and landslide erosion. Their influence on erosion processes is determined by such parameters as: precipitation frequency, amount, duration and intensity. These features affect the rate of infiltration and the intensity of surface runoff, and thus the occurrence, course and effectiveness of erosion processes [2, 3, 4]. The aim of research was to analyse the 40-years of rainfall measurements data from the Lubuskie Voivodeship and inspect whether occurring of heavy rains are random events or maybe indicate some long period trends. To analysis was used non-parametrical Mann Kendall test and correlation test. What is more the authors’ prepared a path of selecting the optimal dewatering system, where would be taken into consideration ground stability and changes in the rainfall trends. For this purpose, the paper contain short overview existing dewatering systems which are used to reducing risk of landslides.
Źródło:
Civil and Environmental Engineering Reports; 2022, 32, 4; 389--409
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trend analysis of flood peaks in lower reaches of Satluj River, Himachal Pradesh, India
Autorzy:
Kumar, S.
Santosh, ---
Powiązania:
https://bibliotekanauki.pl/articles/970628.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
flood peaks
mann-kendall test
satluj river basin
regression
trend analysis.
Opis:
Climate change arising from anthropogenic driven emissions of greenhouse gases has emerged as one of the most important environmental issues in the last two decades. One of the most significant potential consequences of climate change may be alteration in regional hydrological cycle and river flow regimes. Increased temperature is expected to increase the peak flows in snowfed rivers of Himalayas. The changing pattern of regional temperature on flood peaks deserves urgent and systematic attention over a basin which provides an insight view of historical trends. Lower reaches of Satluj River is selected for the present study. Testing the significance of observed trends in flood peaks has received a great attention recently, especially in connection with climate change. The data series available was 48 years (1967-2010). The records were subjected to trend analysis by using both non-parametric (Mann-Kendall test) and parametric (linear regression analysis) procedures. For better understanding of the observed trends, flood peaks were computed into standardised flood peak indices (SFPI). These standardised data series were plotted against time and the linear trends observed were represented graphically. The analysis of flood peaks at different observation stations in lower reaches of Satluj River showed a large variability in the trends and magnitudes. The trend analysis results of flood peaks and gauge heights indicate that the flood peaks at all sites i.e. Rampur, Suni and Kasol show increasing but statistically insignificant trends. The trends in gauge height at all sites are also showing increasing trend but Kasol is statistically significant at 95% confidence level. The fast melting of glaciers, incessant monsoon rainfall and the synchronisation of the discharge peaks are the main causes of river floods. The past flood peaks will help us to observe the frequency of occurrence of floods in certain region and to determine whether the flood peaks in the past have been same with that of the present or whether there is any deviation in the trend in relation to climate change. Such studies will help in designing mitigation and adaptation strategies towards extreme hydrological events.
Źródło:
International Letters of Natural Sciences; 2015, 46
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trend analysis of rainfall in Satluj River Basin, Himachal Pradesh, India
Autorzy:
Kumar, Sandeep
Gill, G. S.
Santosh, Santosh
Powiązania:
https://bibliotekanauki.pl/articles/1193980.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Himachal Pradesh
Mann-Kendall test
Rainfall
Regression
Satluj River Basin
Trend analysis
Opis:
attention recently, especially in connection with climate change. The changing pattern of rainfall deserves urgent and systematic attention for planning, development, utilisation and management of water resources. The daily data on variable were converted to monthly and then computed to seasonal and annual series. Annual rainfall (mm/yr) was calculated as the sum of monthly values. The missing values in the data were computed by using average method. The records of rainfall were subjected to trend analysis by using both non-parametric (Mann-Kendall test) and parametric (linear regression analysis) procedures. For better understanding of the observed trends, data were computed into standardised precipitation indices (SPI). These standardised data series were plotted against time and the linear trends observed were represented graphically. Trend analysis results of rainfall show that out of 15 annual trends 6 (40%) are increasing and 9 (60%) are decreasing in nature where 1 (6.6%) is statistically significant (increasing) and 2 (13.3%) are statistically significant (decreasing) at 95% confidence level. Similarly, the changes were investigated for the four seasons: winter (December-March), pre-monsoon (April-June), monsoon (July-September) and post-monsoon (October-November). The analysis of rainfall, annual as well as seasonal, of different gauge stations in Satluj River Basin showed a large variability in the trends and magnitudes from 1984 to 2010. The rainfall shows great temporal and spatial variations, unequal seasonal distribution with frequent departures from normal. Majority of gauge stations have experienced decreasing trends, both on seasonal and annual scales. Some were statistically significant at 95% confidence level. The sensitivity of rainfall variations provides important insight regarding the responses and vulnerability of different areas to climate change. It will further strengthen the formulation of future strategy for management of water resources.
Źródło:
World Scientific News; 2015, 14; 1-55
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
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