Spatial and Temporal Trend Analysis of Stream Flow in the Kor River and Drought in the Doroodzan Dam Basin

This study analyzes involved trends in stream flow and precipitation data at monthly, seasonal and annual timescales observed at six precipitation and four stream flow stations of Tampa Bay using non-parametric Mann–Kendall (MK) and discrete wavelet transform (DWT) methods. The MK test and sequential MK analysis were applied to different combinations of DWT after removing the effect of significant lag-1 serial correlation to calculate components responsible for trend of the time series. Also, the sequential MK test was used to find the starting point of changes in annual time series. The results showed that negative trend is prevalent in the case study; generally, short-term periods were important in the involved trend at original time series. Thus, the precipitation data at three scales showed short-term periods of 2 months, 6 months and 2 years in monthly, seasonal and annual scales, respectively. In the greatest stream-flow time series at three timescales, wavelet-based detail at level 2 plus the approximations time series was conceded as the dominant periodic component. Finally, the results of Sen's trend analysis, applied to the original annual time series, also confirmed the results of the proposed wavelet-based MK test in most cases.

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Trend Analysis of Stream Flow of Ramganga River Catchment

International Journal of Agriculture Environment and Biotechnology ◽

10.5958/2230-732x.2017.00040.7 ◽

2017 ◽

Vol 10 (3) ◽

pp. 327

Author(s):

Rajesh Kumar ◽

P.R. Ojasvi ◽

V.K. Chandola ◽

A.K. Nema

Keyword(s):

Trend Analysis ◽

Stream Flow ◽

River Catchment ◽

Ramganga River

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Making health technology assessment more dynamic – Temporal trend analysis to capture performance trajectories

Health Policy and Technology ◽

10.1016/j.hlpt.2017.04.005 ◽

2017 ◽

Vol 6 (3) ◽

pp. 328-338

Author(s):

Patrik Hidefjäll ◽

Magnus Backheden

Keyword(s):

Health Technology Assessment ◽

Trend Analysis ◽

Technology Assessment ◽

Temporal Trend ◽

Health Technology

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Trend Analysis of Climate variables, Stream flow and their Linkage at Modjo River Watershed, Central Ethiopia

10.21203/rs.3.rs-16796/v1 ◽

2020 ◽

Author(s):

Kokeb Zena ◽

Tamene Adugna ◽

Fekadu Fufa

Keyword(s):

Climate Variability ◽

Trend Analysis ◽

Stream Flow ◽

Management Practices ◽

River Flow ◽

Pearson Correlation ◽

Kendall Test ◽

Precipitation Series ◽

River Watershed ◽

The Mean

Abstract Background: Trend and variability analysis of precipitation and stream flow series provides valuable information to understand hydrological changes associated with climate variability. In this study, annual and seasonal trends of precipitation and stream flow series and their relationship was investigated over the Modjo river watershed. The Mann-Kendall test and Sen’s slope estimator were used for trend analysis and evaluation of its magnitude respectively, with an approach that corrects the serial correlation. The Pearson correlation analysis was also applied to evaluate the relationships between river flow and precipitation series.Results: the mean and maximum stream flow series showed downward trends at the annual and kiremt time series, whereas no significant trend was observed for the minimum flow over the Modjo watershed. The study indicated that the mean annual and kiremt (monsoon) stream flow decreased significantly at a rate of 8.262 and 6.528 m3s-1per year respectively. In contrary to the river flow, there is no positive or negative trend in the annual and seasonal precipitation series although the tendency was towards increasing trends. It was evidenced that the annual, and kiremt season river flow series was affected abruptly since 2000, however for the same analysis period there was no evidence of changes in precipitation events, which is also not related significantly with the variability of river flow during the analysis period.Conclusions: the river flow decreased dramatically in the Modjo watershed during the analysis period (1981-2015), however it was not primarily associated significantly with climate variability (precipitation & temperature). The result suggests the need of considering the unplanned water extraction and the poor land use management practices to sustain and restore river flow trend observed in the watershed.

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