Your search found 4 records
1 Muratoglu, A.; Iraz, E.; Ercin, E. 2022. Water resources management of large hydrological basins in semi-arid regions: spatial and temporal variability of water footprint of the Upper Euphrates River Basin. Science of the Total Environment, 846:157396. (Online first) [doi: https://doi.org/10.1016/j.scitotenv.2022.157396]
Water resources ; Water management ; Water footprint ; Water conservation ; Transboundary waters ; River basins ; Hydrology ; Water accounting ; Semiarid zones ; Spatial variations ; Temporal variations ; Water use ; Water scarcity ; Crop production ; Precipitation / Middle East / Turkey / Euphrates River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H051360)
(7.86 MB)
The existing water accounts for large-scale, semi-arid and transboundary river basins are usually lack of sufficient spatial-temporal elements of water use, a prerequisite for identifying potential water savings and for sustainable management of scarce water resources. This study aims to demonstrate value of water footprint (WF) accounting framework for such river basins with the case study of the Upper Euphrates River basin which is not only used as major food and energy production resource in Turkey but also a focal point for international conflict, diplomacy and dialogue in Middle East. The methodology is based on Water Footprint Assessment Manual which is published by Water Footprint Network. The study maps spatial-temporal variations of sectoral water use in the study area for the agriculture, domestic water supply and industry for the period of 2008–2019. The water footprint of the Upper Euphrates River basin is calculated as 27.4 Gm3, most of which is related to the agricultural activities. The downstream and lower plains of the study area exhibited a considerably high blue and grey agricultural WF, reaching 2397 and 349 mm, respectively. Several crops have substantially large WFs in the region such as cotton, wheat, pistachio, and barley. The analysis given in this study revealed importance of spatial-temporal disaggregated information in water accounting for sustainable management of water resources. These accounts can provide insights that were not available to the decision makers before, such as water saving opportunities, potential water efficiency and productivity benchmarks, strategic planning for various climatic conditions etc. These are the major values that water footprint accounting can introduce in water management in a large scale, semi-arid transboundary river basins.
2 Hao, L.; Wang, P.; Gojenko, B.; Yu, J.; Lv, A.; Li, F.; Kenjabaev, Shavkat; Kulmatov, R.; Khikmatov, F. 2023. Five decades of freshwater salinization in the Amu Darya River Basin. Journal of Hydrology: Regional Studies, 47:101375. [doi: https://doi.org/10.1016/j.ejrh.2023.101375]
Freshwater ; Salinization ; River basins ; Salinity ; Climate change ; Agriculture ; Discharges ; Hydrology ; Spatial variations ; Seasonal variation ; Models / Central Asia / Amu Darya River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H051880)
https://www.sciencedirect.com/science/article/pii/S2214581823000629/pdfft?md5=4bff9fdaedc0eeba19a4acb52ba0321f&pid=1-s2.0-S2214581823000629-main.pdf
https://vlibrary.iwmi.org/pdf/H051880.pdf
https://vlibrary.iwmi.org/pdf/H051880.pdf
(8.41 MB) (8.41 MB)
Study region: The Amu Darya River (ADR) basin in Central Asia.
Study focus: To understand the spatiotemporal patterns and underlying driving mechanisms of river salinization in arid environments, this study gathered 50 years (1970–2019) of water chemistry data from 12 locations along the ADR. The variations in discharge and salinity were assessed by a linear regression model and violin plot. The salinity-discharge relationships were evaluated by a general hyperbolic model and Spearman’s rank correlation coefficient. Random forest models were also constructed to identify the predominant drivers of river water salinization. Finally, a conceptual model of river water salinization was constructed.
New hydrological insights for the region: The water salinity (S) in the upper stream of the ADR was 541–635 mg/L. Salinity showed an increasing trend along the river course, reaching 751–1560 mg/L downstream. In the downstream, the river salinity before the 1990 s (751–1128 mg/L) was slightly lower than that after the 1990 s (983–1560 mg/L). Generally, water salinity was notably correlated with river discharge (Q) in upstream, exhibiting a relationship of S= 17,497Q- 0.62, p < 0.05, before the 1990 s. Interannual variation in river salinity is mainly controlled by secondary salinization, and intra-annual variation is controlled by river flow. From upstream to downstream, the controlling salinization process changes from primary salinization to secondary salinization. Specifically, secondary salinization has accelerated due to intensified agricultural activities in recent years.
Study focus: To understand the spatiotemporal patterns and underlying driving mechanisms of river salinization in arid environments, this study gathered 50 years (1970–2019) of water chemistry data from 12 locations along the ADR. The variations in discharge and salinity were assessed by a linear regression model and violin plot. The salinity-discharge relationships were evaluated by a general hyperbolic model and Spearman’s rank correlation coefficient. Random forest models were also constructed to identify the predominant drivers of river water salinization. Finally, a conceptual model of river water salinization was constructed.
New hydrological insights for the region: The water salinity (S) in the upper stream of the ADR was 541–635 mg/L. Salinity showed an increasing trend along the river course, reaching 751–1560 mg/L downstream. In the downstream, the river salinity before the 1990 s (751–1128 mg/L) was slightly lower than that after the 1990 s (983–1560 mg/L). Generally, water salinity was notably correlated with river discharge (Q) in upstream, exhibiting a relationship of S= 17,497Q- 0.62, p < 0.05, before the 1990 s. Interannual variation in river salinity is mainly controlled by secondary salinization, and intra-annual variation is controlled by river flow. From upstream to downstream, the controlling salinization process changes from primary salinization to secondary salinization. Specifically, secondary salinization has accelerated due to intensified agricultural activities in recent years.
3 Aryal, Anil; Shrestha, M.; Aryal, S.; Upadhyay, S.; Maharjan, M. 2023. Spatio-temporal variability of streamflow in major and medium rivers of Nepal. Journal of Hydrology: Regional Studies, 50:101590. [doi: https://doi.org/10.1016/j.ejrh.2023.101590]
River basins ; Stream flow ; Climate variability ; Spatial variations ; Temporal variations ; Ecosystem services ; Hydrology ; Trends ; Indicators ; Climate change / Nepal / Karnali River Basin / West Rapti River Basin / Gandaki River Basin / Bagmati River Basin / Koshi River Basin / Kankai Catchment
(Location: IWMI HQ Call no: e-copy only Record No: H052488)
https://www.sciencedirect.com/science/article/pii/S221458182300277X/pdfft?md5=358ff4bf858a2d22283c5affbb08a4fd&pid=1-s2.0-S221458182300277X-main.pdf
https://vlibrary.iwmi.org/pdf/H052488.pdf
https://vlibrary.iwmi.org/pdf/H052488.pdf
(4.62 MB) (4.62 MB)
Study region: We selected six (three on each) major and medium river basins of Nepal as a study domain for the analysis. The study areas were so selected that they represent the river basins across the country from East (Kankai basin) to West (Karnali basin). Study focus: This study focuses on the long-term hydrologic alteration in the river flow of Nepal’s medium and major rivers of different river basins. The overarching objective of the study is to evaluate the spatio-temporal change in flow magnitude, duration, frequency, timing, and rate of change in the major and medium rivers in Nepal. With continuity in the development activities, it is imperative to analyze the potential impact of human activities in the hydrologic regimes. For this, we used a set of 33 indicators from the indicator of hydrologic alteration (IHA) developed by The Nature Conservancy for the pre and post-impact period. The pre and post-impact period is defined here as the time before and after which the substantial alteration occurred, possibly due to multiple reasons. The pre and post impact periods were determined using the Pettitt statistical test carried out at the most downstream of the hydrological gauge station of each river basin. Further, the trends in the annual flow were estimated using the Mann-Kendall test, and the slope of the trend was estimated using Sen’s slope. New hydrological insights for the region: The results showed that in the post-impact period, the mean annual discharge in major and medium rivers of Nepal was found to decrease by 5.86% and 7.94%, respectively. Except for the West Rapti River (- 14.3%), the hydrologic change of 1-day maximum flow is observed to have increased in the medium rivers and decreased in the major rivers. Moreover, except for the Kankai River (+14.29%), the hydrologic change of 1-day minimum flow is observed to be reduced in both the major and medium rivers. In major rivers, the overall degree of alteration ranges from 28.7% to 38.0%, which resembles the low to mid variability range. Similarly, the result of the hydrologic alteration showed that for the medium rivers, the overall degree of alteration varied from 35.8% to 46.7%, representing the medium range of variability. This suggests that the river systems undergoing moderate hydrologic alteration have experienced moderate alteration. These rivers might be capable of sustaining a healthy ecosystem, however, could be more susceptible to other stressors like drought.
4 Wendemeneh, D.; Ayana, M.; Haileslassie, Amare; Lohani, T. K. 2024. Spatiotemporal variation in soil salinity under irrigated fields at Bochessa Catchment in Central Ethiopia. Irrigation and Drainage, 73(2):588-600. [doi: https://doi.org/10.1002/ird.2904]
Soil salinity ; Irrigated farming ; Agriculture ; Irrigated land ; Temporal variations ; Spatial variations ; Farmers ; Soil properties / Ethiopia / Bochessa Catchment
(Location: IWMI HQ Call no: e-copy only Record No: H052482)
(0.53 MB)
Soil salinity and sodicity problems are one of the major challenges to the permanence of irrigated agriculture in Ethiopia. This manuscript, therefore, concerns its spatial and temporal variation under irrigated fields and suggests possible management options. For this investigation, eight monitoring locations were selected based on the irrigation intensity that farmers practised in the area. With each location, three irrigated farmers' fields were randomly selected for sampling purposes. Likewise, six farmers' fields from the rain-fed system were also selected for comparison purposes. Sampling was performed at the beginning and end of each cropping season for three consecutive years from 2017 to 2019. The major physical and chemical properties of the soil were analysed in accordance with standard laboratory procedures. A linear model of two-way analysis of variance was used to analyse parameters across time and space. The results indicated that the majority of the soil properties studied showed significant differences (p < 0.05) over time. This implies that the change is in accordance with the seasonal soil property, possibly due to irrigation practices. Similarly, approximately 90% of the soil properties studied showed noticeable differences (p < 0.05) across locations. Almost all salinity indicators showed an increasing trend in irrigated fields compared to their situation in rain-fed fields. For instance, the electrical conductivity (EC) and exchangeable sodium percentage (ESP) values across the fields ranged from 0.54 to 0.82 dS m ¹ and 8–1%, respectively, with maximum values observed in irrigated fields. This implies that irrigation practices influence soil properties in the area. In addition, the ESP values approaching the maximum permissible limit suggest that sodicity may cause more problems than salinity in the area. Therefore, agronomic practices (e.g. residue management, deep tillage, salttolerant crops and periodic fallowing), irrigation and drainage management practices, and amendments may help farmers mitigate salinity and sodicity problems in the area.
Powered by DB/Text WebPublisher, from
