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Climate Change and Water Resources Management in the Ghis-Nekor Watershed (North of Morocco) – A Comprehensive Analysis Using SPI, RDI and DI Indices

Benyoussef Said, Arabi Mourad, El Yousfi Yassine, Cheikh Boumediene Ben, Abdaoui Abdellali, Azirar Maryam, Mechkirrou Latifa, El Ouarghi Hossain, Zegzouti Younes Filali, Boughrous Ali Ait

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 2

199--209

EN

Morocco is currently facing significant challenges due to the ever–changing climate, with its critical water sources crucial for agriculture, economy, and daily life being greatly affected. In order to thoroughly understand the impact of climate change on the Ghis–Nekor watershed, an in–depth study spanning 38 years (1978–2016) was conducted. This involved examining the meteorological data from three stations and utilizing advanced indices, such as SPI, RDI, and DI. The findings of this study revealed prominent shifts in precipitation patterns, indicating a vulnerability in the region. While there was a general increase in annual rainfall during the specified time period, a sharp decline was observed post–2008. Further analysis of drought confirmed the presence of persistent dry spells and recurring episodes, highlighting the urgent need for effective water management strategies. These crucial findings must be considered by decision–makers for successful climate adaptation, emphasizing the key role played by this study in mitigating the effects of climate change.

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Characterization of Climatic Drought Sequences in the Upper Moulouya Watershed, Morocco

Hachem Abdelaaziz, Mili El-Mostafa, Benbella Bouchra, El Ouardi Hmidou, Mehdaoui Radouan

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 2

162--179

EN

Like most of the countries of the African continent and the MENA, Morocco has experienced alternating wet and dry periods for several decades and is still confronted with the effects of unstable climate change due to the specificities conferred by its geographical position and the diversity of its ecosystems. It is one of the countries most affected by desertification, with an arid and semi-arid climate covering more than 93% of its territory. Indeed, the Upper Moulouya watershed has been exposed to severe droughts several times in recent decades. The spatial and temporal distribution of drought episodes in this watershed is studied over a 91-year period between 1931 and 2022. In order to characterize and evaluate the severity and sustainability of drought in this watershed, four indices were used and applied in this study, as they have advantages in terms of statistical consistency and have the capacity to describe, through different time scales (short, medium and long) the impacts of the climatic drought in question. These are the Standardized Precipitation Index SPI, RDI, RI and DI. The annual rainfall series at the eight meteorological stations of the said watershed show irregularities and very marked spatial and temporal variability with a generally decreasing trend. The SPI calculation results obtained show a heterogeneous distribution of SPI values throughout the watershed area. The analysis of the graphical illustrations of this index allowed to highlight an important fluctuation of the dry and wet periods with a strong dominance and tendency to drought with the order of 51% in the stations of Midelt, and Ansegmir, 52% in the station of Zaida, 59% in the stations of Tabouazant, Barrage (Dam) Enjil and El Aouia, 58% in the station of Louggagh, 47% in the station of Anzar Oufounes. The analysis of the results of the of the drought indices RDI, RI and DI at the level of this watershed also made it possible to highlight the existence of numerous drought sequences alternating with other wet sequences and indicates a dominance of dry years, perfectly remarkable during the period 1976-93. The most important dry episode, in number of successive years, was recorded at the Ansegmir station from 1976-89 and the most important rainy episode was recorded at the Midelt station from 1966-76. The years of the 2015-2022 series show an overall persistent decrease in rainfall, thus allowing the installation of a severe drought episode. The trend in the entire watershed is a decrease in rainfall and the installation of mild, moderate and severe drought episodes of varying length and duration.

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Regulated deficit irrigation of rhododendrons grown in containers

Matysiak B., Koniarski M., Treder W.

Infrastruktura i Ekologia Terenów Wiejskich

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2017

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nr II/1

509--519

EN

The effect of deficit irrigation imposed in July-August period on shoot growth and flower formation in container grown rhododendron in commercial nursery were assessed. Plants were exposed to three irrigation regimes based on potential evapotranspiration rates (100% ET0 - well-watered control plants, 75% ET0 - moderate drought and 50% ET0 - severe drought). The values of evapotranspiration were calculated using the Penman-Monteith model. The degree of drought had significant effect on the plant growth and water status of plants. Severe drought inhibited secondary shoot elongation compared to less stressful regime but did not affect flower formation. ‘Catawbiense Boursault’, ‘Nova Zembla’ and ‘Pearce’s American Beauty’ plants exposed to severe drought were shorter, respectively by 39, 45 and 86% than well-irrigated plants and two of the three cultivars ‘Catawbiense Boursault’ and ‘Pearce’s American Beauty’ produced fewer secondary branches (5.9 and 0.3) compared to control plants (9.2 and 1.7, respectively). Moderate drought did not affect plant growth but resulted in flower bud formation in ‘Nova Zembla’ and ‘Pearce’s American Beauty’s cultivars. Estimated water consumption by rhododendrons throughout the whole growing season was reduced by 15% for moderate and 25% for severe drought compared to control, well-watered plants. The results have significant implications for water conserving in commercial production of rhododendrons.

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Effect of regulated deficit irrigation imposed in the fall on cold hardiness of woody plants

Matysiak B., Treder W.

Infrastruktura i Ekologia Terenów Wiejskich

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2017

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nr II/1

555--566

EN

In temperate zone, early freeze, particularly if preceded by a period of warm and wet weather, can severely injure many woody plants. The young plants are particularly sensitive to frost, especially those grown in containers. The timing and capacity of cold acclimation are modified by environmental cues. We examined whether regulated deficit irrigation (RDI) imposed in the fall affects cold acclimation of containerized Lawson cypress (Chamaecyparis lawsoniana)‘Columnaris’ and Knaphill-Exbury azalea (Rhododendron) ‘Oxydol’. Three-year-old plants were grown in containers placed in the open field and were cultivated according to standard nursery practice. In the end of growing season (from 5th October to 2nd November 2015, half of the plants were expose to moderated water stress by ceasing irrigation and protecting them from the rain (RDI treatment). The volumetric water content of the growing medium gradually decreases in this time from 0.45 to 0.2 m3/m3. Irrigation of the second part of the plants were continued in October and water content was maintained at 0.45 m3/m3 (control treatment). Cold hardiness of stem tissues was assessed two times (2nd November and 7th December) in the laboratory using the ion-leakage test. Stem tissue were exposed to 6 test temperatures, ranging from +4 to – 26˚C. Additionally, plant quality after overwintering was evaluated. Freeze tolerance of plant stems of both woody plants was significantly higher in December than November. Regulated deficit irrigation (RDI) generally increased cold hardiness of Lawson cypress in November as well as in December. At RDI treatment, ion-leakage from plant tissue frozen to - 26˚C was lower by 20% in the first time of assessment, and by 8% in the second time. Regulated deficit irrigation (RDI) increased cold hardiness of azalea stems only in November, but did not affect frost hardiness in December. At water deficit treatment, ion-leakage from plant tissue frozen to - 26˚C was lower by 12% than at control treatment. This study demonstrated that reduced water supply early autumn promoting acclimating to low winter temperatures.