The influence of climate change on discharge fluctuations in Slovenian rivers

In recent decades, an increase in the number of extreme flood events as well as extreme drought events has been observed in Slovenia. This rise the need for a comprehensive analysis of trends in discharge data series. In the study, statistical trends in seasonal and annual mean, maximum, extreme and low discharge values were investigated using the Mann Kendall test. The results show a temporal and spatial variability of trends in discharge. In general, a decreasing trend in water quantities in the rivers was observed. However, results at some gauging stations indicate statistically significant increasing trends, especially for maximum and extreme discharges. Additional analyses show that the discharge trends depend on the location of the gauging station.

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Rainfall and runoff regime trends in mountain catchments (Case study area: the upper Hron River basin, Slovakia)

Journal of Hydrology and Hydromechanics ◽

10.1515/johh-2015-0030 ◽

2015 ◽

Vol 63 (3) ◽

pp. 183-192 ◽

Cited By ~ 9

Author(s):

Andrea Blahušiaková ◽

Milada Matoušková

Keyword(s):

River Basin ◽

Kendall Test ◽

Winter Period ◽

Data Series ◽

Flood Events ◽

Mann Kendall Test ◽

Runoff Regime ◽

Simple Mass ◽

Hydroclimatic Variables

Abstract This paper presents an analysis of trends and causes of changes of selected hydroclimatic variables influencing the runoff regime in the upper Hron River basin (Slovakia). Different methods for identifying trends in data series are evaluated and include: simple mass curve analysis, linear regression, frequency analysis of flood events, use of the Indicators of Hydrological Alteration software, and the Mann-Kendall test. Analyses are performed for data from two periods (1931-2010 and 1961-2010). The changes in runoff are significant, especially in terms of lower QMax and 75 percentile values. This fact is also confirmed by the lower frequency and extremity of flood events. The 1980s are considered a turning point in the development of all hydroclimatic variables. The Mann-Kendall test shows a significant decrease in runoff in the winter period. The main causes of runoff decline are: the considerable increase in air temperature, the decrease in snow cover depth and changes in seasonal distribution of precipitation amounts.

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Aspects of seasonality and flood generating circulation patterns in a mountainous catchment in south-eastern Germany

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-4-589-2007 ◽

2007 ◽

Vol 4 (2) ◽

pp. 589-625 ◽

Cited By ~ 5

Author(s):

T. Petrow ◽

B. Merz ◽

K.-E. Lindenschmidt ◽

A. H. Thieken

Keyword(s):

Flood Frequency ◽

Flood Frequency Analysis ◽

Flood Events ◽

Statistical Parameters ◽

Discharge Data ◽

Eastern Germany ◽

South Eastern ◽

Circulation Patterns ◽

Extreme Flood ◽

Large Floods

Abstract. Analyses of discharge series, precipitation fields and flood producing atmospheric circulation patterns reveal that two governing flood regimes exist in the Mulde catchment in south-eastern Germany: frequent floods during the winter and less frequent but sometimes extreme floods during the summer. Differences in the statistical parameters skewness and coefficient of variation of the discharge data can be found from west to east and are discussed in the context of landscape parameters that influence the discharge. Annual maximum discharge series were assigned to the triggering Großwetterlage in order to evaluate which circulation patterns are likely to produce large floods. It can be shown that the cyclone Vb-weather regime generates the most extreme flood events in the Mulde catchment, whereas westerly winds produce frequently small floods. Vb-weather regimes do not always trigger large flood events in the study area, but large floods are mostly generated by these weather patterns. Based on these findings, it is necessary to revise the traditional flood frequency analysis approach and develop new approaches which can handle different flood triggering processes within the dataset.

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Ectomycorrhiza resilience and recovery to extreme flood events in Tuber aestivum and Quercus robur

Mycorrhiza ◽

10.1007/s00572-021-01035-4 ◽

2021 ◽

Author(s):

P. W. Thomas

Keyword(s):

Climate Change ◽

Seedling Growth ◽

Quercus Robur ◽

Root Systems ◽

Fruiting Bodies ◽

Flood Events ◽

Tuber Aestivum ◽

Soil Zone ◽

Extreme Flood ◽

The Impact

AbstractVery little is known about the impact of flooding and ground saturation on ectomycorrhizal fungi (EcM) and increasing flood events are expected with predicted climate change. To explore this, seedlings inoculated with the EcM species Tuber aestivum were exposed to a range of flood durations. Oak seedlings inoculated with T. aestivum were submerged for between 7 and 65 days. After a minimum of 114-day recovery, seedling growth measurements were recorded, and root systems were destructively sampled to measure the number of existing mycorrhizae in different zones. Number of mycorrhizae did not display correlation with seedling growth measurements. Seven days of submersion resulted in a significant reduction in mycorrhizae numbers and numbers reduced most drastically in the upper zones. Increases in duration of submersion further impacted mycorrhizae numbers in the lowest soil zone only. T. aestivum mycorrhizae can survive flood durations of at least 65 days. After flooding, mycorrhizae occur in higher numbers in the lowest soil zone, suggesting a mix of resilience and recovery. The results will aid in furthering our understanding of EcM but also may aid in conservation initiatives as well as providing insight for those whose livelihoods revolve around the collection of EcM fruiting bodies or cropping of the plant partners.

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