Trends of mean annual river discharges in the Zapadna Morava river basin

Abstract

Zapadna Morava River basin covers a surface of 15850 km2, which is approximately 18% of the territory of the Republic of Serbia. In its basin, 38 active surface stations are registered. The goal of this paper is the trend analysis of the mean annual river discharges in the Zapadna Morava River basin and their noticing in a longer series of time, as well as determining their intensity. Fifty years period of time (1965 - 2014) is taken for a time series. Because there is no empirical data for mean annual discharge values for all stations for the given period, the number of the hydrological stations, which are processed in this paper, is reduced to 21. Mann-Kendall test has been used for noticing the trend, Sen test has been used for estimating the curves inclinations of the linear trend, while Pettitt?s test has been used for determining the turning point of change. Also, classification of the years by water richness has been performed in this paper in order to determine wet and dry periods. For the needs of identification of medium watery, wet and dry years, the combined method has been used on the data examples from representative stations in the basin. Based on the processed data and the obtained results, it has been established that the most rivers in the basin of the Zapadna Morava River have a slightly decreasing trend of the flow values, whereby the change of the trend is not significant. On the most rivers, the change period has begun in the early eighties of the past century. On a large number of profiles, the watery period was appearing in the beginning of eighties, while the dry season is characteristic for the period from 1990 to 1994.

Assessment of torrential flood and landslide susceptibility of terrain: Case study - Mlava River Basin (Serbia)

“…Појавом интензивних падавина, наглим топљењем снега или коинциденцијом ових појава, долази до формирања интензивног површинског отицаја и покретања материјала еродованог са падина у хидрографску мрежу, брзе концентрације вода и формирања бујичног поплавног таласа (Ristić & Malošević, 2011;Lovrić & Tošić, 2017). Са еколошког аспекта, појава бујичних поплава може значајно смањити квалитет површинских вода услед повећане концентрације материја физичког, хемијског и микробиолошког карактера (Langović et al, 2017;Doderović et al, 2020;Durlević, 2020).…”

“…The appearance of intense precipitation, sudden snow melting or coincidence of these phenomena, leads to the formation of intense surface runoff and the movement of material eroded from the slopes into the hydrographic network, rapid water concentration and the formation of torrential flood waves (Ristić & Malosević, 2011;Lovrić & Tosić, 2017). From the environmental aspect, the occurrence of torrential floods can significantly reduce the quality of surface waters due to the increased concentration of substances of physical, chemical and microbiological character (Langović et al, 2017;Doderović et al, 2020;Durlević, 2020).…”

Assessment of the soil loss caused by riverbank erosion in Serbia

“…The direct dependence of riverbank erosion from the river discharge variations was expected, but there are differences depending on the registered trend of the discharges during the study period. Various studies (Kovačević-Majkić & Urošev, 2014;Langović, 2017;Bloch et al, 2019) have confirmed the existence of a decreasing trend of the mean annual discharge values of the rivers in Serbia, but a growing trend in the occurrence of extreme hydrological conditions under the influence of climate change. Therefore, the pressure on the river banks became more pronounced.…”

Анализа Протицаја На Ријеци Сани

“…На овај начин могуће је пратити промјене у водном режиму ријека. Употреба овог метода у хидролошким и географским проучавањима указује на тренд у вишегодишњем режиму водности једног тока (Langović et al, 2017;Мустафић, 2012). На основу просјечне годишње вриједности протицаја у анализираном периоду и његове стандардне девијације, извршено је рангирање година по водности, по принципу (Оцокољић, 1994):…”

“…In this manner, it is possible to monitor changes in the water regime of the rivers. The usage of this method in hydrological and geographical studies can indicate a trend in a long-term water regime of a single river basin (Langović et al, 2017;Мустафић, 2012). Based on the mean annual discharge values during target periods and the standard deviations, the years were ranked based on wateriness according to the following principle (Оцокољић, 1994): < -3δ Катастрофално сушна година / Catastrophically dry year -3δ − -2δ Веома сушна година / Very dry year -2δ − -1δ Сушна година / Dry year -1δ − 1 δ Средње водна година / Average wateriness 1δ − 2 δ Водна година / Watery year 2δ − 3δ Веома водна година / Very watery year > 3δ Катастрофално водна година / Catastrophically watery year У циљу утврђивања утицаја климатских промјена на протицај ријеке Сане, израчунати су трендови средњих годишњих и сезонских температура ваздуха и средњих висина падавина на метеоролошкој станици Приједор у периоду 1961-2014. године.…”