Hydrological Drought in Tafna Basin-Northwest of Algeria (original) (raw)
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Drought has become a recurrent phenomenon in Algeria in the last few decades. Significant drought conditions were observed during the late 1980s and late 1990s. The agricultural sector and water resources have been under severe constraints from the recurrent droughts. In this study, spatial and temporal dimensions of meteorological droughts in the Wadi Mina basin (4900 km2) were investigated to assess vulnerability. The Standardized Precipitation Index (SPI) method and GIS were used to detail temporal and geographical variations in drought based on monthly records for the period 1970–2010 at 16 rainfall stations located in the Wadi Mina basin. Trends in annual SPI for stations in the basin were analyzed using the Mann–Kendall test and Sen’s slope estimator. Results showed that the SPI was able to detect historical droughts in 1982/83, 1983/84, 1989/90, 1992/93, 1993/94, 1996/97, 1998/99, 1999/00, 2004/05 and 2006/07. Wet years were observed in 1971/72, 1972/73, 1995/96, 2008/09 and ...
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Drought is one of the most serious problems for human societies and ecosystems, caused by climate variability. This phenomenon is of great importance in the world, especially in North Africa Countries like Algeria. In this study, rainfall of 16 stations in the Wadi Mina Basin (4900 km²), in the Northwest of Algeria were statistically analysed over a 40 years period (1970/71- 2009/10). The Principal Component Analysis (PCA) application showed that the first principal component (PC1) explains more than 66 % of the variance. Rainfall data showed two different periods: a wet period from (1970 to 1980 and from 2008 to 2009) and a dry period from 1980 to 2007. The basic characteristics of drought; duration, intensity and frequency were studied. Several recommendations are proposed for a good water management to alleviate the impact of these climatic changes. Strategic measures will be taken, such as, sensitizing the population for water economy, generalization of localised irrigations sys...
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In Algeria, water resources, which depend to a large extent on irregular rainfall, remain modest in relation to the deficit and the means of retention. The study of precipitation recorded at several meteorological stations in northern Algeria (1951-1980, 1961-1990 and 2001-2010) shows the evolution of successions of excessive and insufficient rainfall episodes compared to Normal. The intra-annual variability of precipitation is greater for coastal stations than for continental stations. The regionalization, obtained thanks to the isohyets, shows the existence of three regions characterized by different types of precipitation. A superimposition of this map with that of the existing hydraulic retention infrastructures makes it possible to have an idea of the efficiency of the recovery and the retention of rainwater in Algeria. Keys words: Rainfall Drought Regionalization Hydraulic Infrastructure INTRODUCTION variability and consequently the general climate Algeria is the largest count...
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Drought is considered a natural hazard and has become a recurrent phenomenon in Algeria since the 1970s. Algeria is characterized by three different climates, namely, sub-humid, semi-arid and arid climates. In this study, we aimed to spatiotemporally assess drought hazard, vulnerability and risk in the three climates of three sub-basins, namely, the Seybouse Maritime, Wadi Djelfa-Hadjia and Wadi M’Zi sub-basins. To this end, the standardized precipitation index (SPI) and the reconnaissance drought index (RDI) were used to evaluate drought physical characteristics on a 12-month timescale, based on precipitation and temperature monthly data covering the period of 1979–2019. High values of the coefficient of determination (R2) (0.76–0.99) confirmed by low values of the root-mean-square error (RMSE) (0.08–0.49) proved that the drought indices displayed a high correlation. Drought hazard and vulnerability were evaluated based on physical characteristics and socioeconomic aspects, respect...
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A three decade-long study on the variability of drought in relation to the contribution of rainfall was conducted at the Wadi Mekerra watershed, located in northwest Algeria, covering the period from 1973 to 2005. The runoff and rainfall data were analyzed using the Mann-Kendall test, the double mass curve method and the SPI index. A rupture of the studied series appeared during the 1980s. The rainfall and runoff trends and contributions were in general, sharply reduced. The region experienced extreme drought between 1981 and1989, and between 1993 and 2001, rainfall contributions were greater than 60%. This increase, which was recorded in August, September and October for all the parameters studied, shows the importance of the superficial runoff component when combined with decreased infiltration. These climatic conditions reduce the natural recharging of groundwater, and cause an increased susceptibility to soil erosion, reduced agricultural production and an increased risk of floods.