Your search found 29 records
1 Haileslassie, A.; Peden, D.; Gebreselassie, S.; Amede, Tilahun; Wagnew, A.; Taddesse, G. 2009. Livestock water productivity in the Blue Nile Basin: assessment of farm scale heterogeneity. Rangeland Journal, 31(2):213-222. [doi: https://doi.org/10.1071/RJ09006]
Livestock ; Feeds ; Water productivity ; Farming systems ; Crop management ; Evapotranspiration ; River basins ; Land use ; Poverty ; Water depletion ; Households ; Surveys / Ethiopia / Egypt / Sudan / Blue Nile Basin / Gumera Watershed
(Location: IWMI HQ Call no: IWMI 636 100 AME Record No: H042281)
(0.37 MB)
A recent study of the livestock water productivity (LWP), at higher spatial scales in the Blue Nile Basin, indicated strong variability across regions. To get an insight into the causes of this variability, we examined the effect of farm households’ access to productive resources (e.g. land, livestock) on LWPin potato–barley, barley–wheat, teff–millet and rice farming systems of the Gumera watershed (in the Blue Nile Basin, Ethiopia). We randomly selected 180 farm households. The sizes of the samples, in each system, were proportional to the respective system’s area. Then we grouped the samples, using a participatory wealth ranking method, into three wealth groups (rich, medium and poor) and used structured and pretested questionnaires to collect data on crops and livestock management and applied reference evapotranspiration (ET0) and crop coefficient (Kc) approaches to estimate depleted (evapotranspiration) water in producing animal feed and food crops. Then, we estimated LWPas a ratio of livestock’s beneficial outputs to water depleted. Our results suggest strong variability of LWP across the different systems: ranging between 0.3 and 0.6 US$ m3 year1. The tendency across different farming systems was comparable with results from previous studies at higher spatial scales. The range among different wealth groups was wider (0.1 to 0.6 US$ m3 year1) than among the farming systems. This implies that aggregating water productivity (to a system scale) masks hotspots and bright spots. Our result also revealed a positive trend between water productivity (LWPand crop water productivity, CWP) and farm households’ access to resources. Thus, we discuss our findings in relation to poverty alleviation and integrated land and water management to combat unsustainable water management practices in the Blue Nile Basin.
2 Pietz, D.; Giordano, Mark. 2009. Managing the Yellow River: continuity and change. In Molle, Francois; Wester, P. (Eds.). River basin trajectories: societies, environments and development. Wallingford, UK: CABI; Colombo, Sri Lanka: International Water Management Institute (IWMI). pp.99-122. (Comprehensive Assessment of Water Management in Agriculture Series 8)
River Basin development ; River basin management ; Governance ; History ; Water depletion / China / Yellow River
(Location: IWMI HQ Call no: IWMI 333.9462 G000 MOL Record No: H042380)
3 Marjanizadeh, Sara; Qureshi, Asad Sarwar; Turral, Hugh; Talebzadeh, P. 2009. From Mesopotamia to the third millennium: the historical trajectory of water development and use in the Karkheh River Basin, Iran. Colombo, Sri Lanka: International Water Management Institute (IWMI). 43p. (IWMI Working Paper 135) [doi: https://doi.org/10.3910/2010.206]
River basin development ; History ; Water use ; Water policy ; Water rights ; Water scarcity ; Land use ; Land policies ; Water depletion ; Groundwater ; Stream flow ; Wetlands / Iran / Karkheh River Basin
(Location: IWMI HQ Call no: IWMI 333.9162 G690 MAR Record No: H042878)
(664.26 KB)
The Karkheh River Basin is the third largest basin in Iran after Karoon and Dez, and occupies a strategic position on the western boundary of the country. The basin has seen remarkable ancient feats of engineering, and has a long history of wheat and barley production, complemented by horticulture. With the growth of the modern nation-state of Iran, water development has progressed steadily in tandem with rising populations and urbanization. The report aims to understand the historical setting and present situation of water development and allocation, in relation to rural development and agrarian policy. It provides the contextual backdrop for further research on the management of water to improve livelihoods in the basin through integrated and sustainable management of land and water resources. It provides further information on the changes in surface flows out of the component subbasins and looks at the development, use and consequences of groundwater abstraction.
4 Winkelmann, D. L. 2004. Consumption trend implications on water depletion. In Stockholm International Water Institute (SIWI); International Water Management Institute (IWMI). Water – more nutrition per drop: towards sustainable food production and consumption patterns in a rapidly changing world. Stockholm, Sweden: Stockholm International Water Institute (SIWI); Colombo, Sri Lanka: International Water Management Institute (IWMI). pp.18-21.
(Location: IWMI HQ Call no: IWMI 631.7.2 G000 SIW Record No: H043338)
(0.26 MB)
5 Giordano, Mark; Pietz, D. 2011. Adaptation and change in Yellow River management. In Grafton, R. Q.; Hussey, K. (Eds.). Water resources planning and management. Cambridge, UK: Cambridge University Press. pp.705-723.
River basin management ; River basin development ; Water user associations ; Water rates ; Pricing ; Water depletion ; History / China / Yellow River
(Location: IWMI HQ Call no: e-copy only Record No: H043600)
(0.44 MB)
6 Lannerstad, M. 2002. Consumptive water use feeds the world and makes rivers run dry. MSc thesis. Stockholm, Sweden: Royal Institute of Technology. 73p. (TRITA-LWR Master Thesis 02-13)
Rivers ; River basin management ; Water depletion ; Water use ; Water accounting ; Food production ; Irrigated farming ; Rainfed farming ; Population growth ; Freshwater ; Plant water relations / South Asia / Colorado River / Ebro River / Nile River / Amu Darya River / Syr Darya River / Aral Sea / Indus River / Ganges River / Yellow River / Huang He River / Murray Darling River Basin
(Location: IWMI HQ Call no: 551.483 G000 LAN Record No: H043897)
(0.12 MB)
7 Amarasinghe, Upali A.; Damen, B.; Eriyagama, Nishadi; Soda, W.; Smakhtin, Vladimir. 2011. Impacts of rising biofuel demand on local water resources: case studies in Thailand and Malaysia. [Report of the IWMI-FAO Bioenergy in Asia and the Pacific Project]. Bangkok, Thailand: FAO. 35p.
Bioenergy ; Biofuels ; Water resources ; Water depletion ; Water use ; Water quality ; Wastewater ; Water storage ; Case studies ; Crop production ; Sugarcane ; Cassava ; Ethanol ; Palm oils ; Biodiesel ; Policy ; Irrigation / Southeast Asia / Thailand / Malaysia
(Location: IWMI HQ Call no: IWMI Record No: H044393)
(5.13 MB)
8 Karimov, Akmal; Molden, David; Platonov, Alexander; Khamzina, A. 2011. From improved water accounting to increased water productivity in the Fergana Valley. In ICID. 21st Congress on Irrigation and Drainage: Water Productivity towards Food Security, Tehran, Iran, 15-23 October 2011. New Delhi, India: ICID. pp.141-153. (ICID Transaction No. 30-A)
Water resources ; Water accounting ; Water productivity ; River basins ; Upstream ; Downstream ; Water depletion ; Water conservation ; Water use ; Evaporation / Central Asia / Uzbekistan / Fergana valley / Syrdarya River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H044425)
http://www.irncid.org/GetFileArticles.aspx?FilePrm=8327_12461.pdf
https://vlibrary.iwmi.org/pdf/H044425.pdf
https://vlibrary.iwmi.org/pdf/H044425.pdf
(1.06 MB) (1.07MB)
Facing competition for limited water resources with domestic, industrial, hydropower and environmental uses, agriculture has to adapt to produce more food with less water. This paper proposes to apply water accounting procedure to identify the scope for water productivity improvement. The Fergana Valley, a highly productive area within the upstream of the Syrdarya River Basin, was selected to examine the proposed procedure. Significant non-productive depletions of water as evaporation at 31-34% of the available water were identified in the Fergana Valley. There is also flow to sinks and pollution in the downstream at 1-5% of the gross inflow due to the changes of the river flow regime, its quantity and quality, caused by the return flow from the irrigated land and the winter hydropower releases from the upstream. Total non-productive depletions of water at 4,200-5,200 million m3 (Mm3) were identified in the form of evaporation, flows to sinks, and pollution. Proper water saving technologies to reduce non-productive depletions will improve water productivity in the Fergana Valley and increase water availability for the downstream water uses.
9 Damen, B.; Tvinnereim, S. (Eds.) 2012. Sustainable bioenergy in Asia: improving resilience to high food prices and climate change. Selected papers from a conference held in Bangkok from 1 to 2 June 2011. Bangkok, Thailand: FAO. 105p. (Regional Conference for Asia and The Pacific (RAP) Publication 2012/14)
Bioenergy ; Energy generation ; Biomass ; Technology ; Food prices ; Food security ; Climate change ; Rural development ; Poverty ; Ethanol ; Feedstocks ; Sorghum ; Rice ; Economic aspects ; Financing ; Public-private cooperation ; Environmental effects ; Case studies ; Policy ; Indicators ; Households ; Water resources ; Water depletion ; Water quality ; Pumping / Asia / Thailand
(Location: IWMI HQ Call no: e-copy only Record No: H045193)
(5.47 MB) (4.9MB)
10 Amarasinghe, Upali; Damen, B.; Eriyagama, Nishadi; Soda, W.; Smakhtin, Vladimir. 2012. Water and bioenergy – a case study from the Thai ethanol sector. In Damen, B.; Tvinnereim, S. (Eds.). Sustainable bioenergy in Asia: improving resilience to high food prices and climate change. Selected papers from a conference held in Bangkok from 1 to 2 June 2011. Bangkok, Thailand: FAO. pp.37-42. (Regional Conference for Asia and The Pacific (RAP) Publication 2012/14)
Bioenergy ; Biofuels ; Case studies ; Ethanol ; Water resources ; Water depletion ; Water quality / Thailand
(Location: IWMI HQ Call no: e-copy only Record No: H045194)
(0.51 MB)
Modern bioenergy systems are attracting increasing attention from governments in Asia as a potential solution to a range of policy problems related to energy security and sustainable development. Despite growing interest in bioenergy systems, there is still a limited understanding of how their expansion could impact on natural resources such as water. This paper aims to shed some light on the relationship between modern bioenergy development and water depletion using a case study on the biofuel sector in Thailand. This case study also includes an assessment of the impact of biofuel developments on water quality in water systems proximate to bioenergy production facilities in Thailand.
11 El-Agha, D. E.; Molden, David; Ghanem, A. M. 2011. Performance assessment of irrigation water management in old lands of the Nile Delta of Egypt. Irrigation and Drainage Systems, 25(4):215-236. [doi: https://doi.org/10.1007/s10795-011-9116-z]
Irrigation water ; Water management ; Deltas ; Water saving ; Evapotranspiration ; Indicators ; Cropping patterns ; Water supply ; Water depletion ; Water productivity ; Canals ; Economic aspects / Egypt / Nile Delta
(Location: IWMI HQ Call no: PER Record No: H045473)
http://download.springer.com/static/pdf/222/art%253A10.1007%252Fs10795-011-9116-z.pdf?auth66=1354689115_e0ae8e40ad7ce8470b7d3d9088e41ab3&ext=.pdf
https://vlibrary.iwmi.org/pdf/h045473.pdf
https://vlibrary.iwmi.org/pdf/h045473.pdf
(1.51 MB) (1.51MB)
This paper provides the methodology and results of a cross-scale diagnostic performance assessment program of the irrigation water management in the old lands of the Nile Delta of Egypt. The analysis was done at three levels; main canal level, branch canals level and on-farm level of the Meet Yazid command (82,740 ha) for the year 2008–2009 to highlight areas for improvement. At the main canal level the annual average percentage of irrigation water returning to drains and groundwater was 53% of the total water supplied. Since Meet Yazid lies at tail end of the delta, and there is groundwater salinity, opportunities for reuse are increasingly limited moving north to Lake Burullus. This would indicate opportunities for real water savings. The results of monthly relative water supply of the main canal indicated mismatch between demand and supply especially during the winter months, and when supply is low farmers do reuse drainage or groundwater. Also, the assessment of the three branch canals showed non-uniformity of water distribution and mismatch between demand and supply even when comparing improved and non-improved canals. At the on-farm level in paddy fields, the amount of irrigation flows to drains and saline sinks varied from 0.46 to 0.71 of inflow. In spite of these values of non-uniformity and low depleted fraction, the relative evapotranspiration (ratio of actual to potential) evaporation was uniformly high, indicating most crops of most farmers were not water stressed, which is also confirmed by the high yield values. The average values of productivity per unit water depleted by ETact were 1.04 and 1.05 kg/m 3 for rice and wheat fields, respectively, with yields of rice and wheat at 8 and 6 t per ha respectively. On farm and tertiary improvements alone will not yield real water savings, as excess water in the main canal and drains will continue to flow out of the system. Rather the focus should first be on supplies to the main canal, accompanied by more precise on farm and water delivery practices at branch and tertiary levels, and ensuring that environmental flows are met. There is an added advantage of focusing on this tail end region of Egypt that this response would lessen vulnerability to reuse of polluted and saline water.
12 Findikakis, A. N.; Sato, K. 2011. Groundwater management practices. Leiden, Netherlands: CRC Press - Balkema. 425p. (IAHR Monograph)
Groundwater management ; Water resources ; Water scarcity ; Water use ; Water supply ; Water depletion ; Aquifers ; Water storage ; Water quality ; Monitoring ; Salt water intrusion ; Hydrology ; River basins ; Rain ; Pumping ; Artificial recharge ; International waters ; Resource depletion ; Organizations ; Case studies ; Economic aspects ; Environmental effects ; Socioeconomic environment ; Land use ; Legal aspects ; Regulations ; Standards ; Climate change ; Drought ; Models / Japan / China / India / Spain / USA / North China Plain / Karnataka State / Jammu / Kashmir / Texas / Los Angeles / South Australia
(Location: IWMI HQ Call no: 333.91 G000 FIN Record No: H045643)
(0.32 MB)
13 Karimi, Poolad; Bastiaanssen, W. G. M.; Molden, D. 2013. Water accounting plus (WA+) – a water accounting procedure for complex river basins based on satellite measurements. Hydrology and Earth System Sciences, 17(7):2459-2472. [doi: https://doi.org/10.5194/hess-17-2459-2013]
Water management ; Water accounting ; Water depletion ; Water storage ; Flow discharge ; Indicators ; River basins ; Satellite surveys ; Land use ; Evapotranspiration ; Ecosystems / Australia
(Location: IWMI HQ Call no: e-copy only Record No: H045939)
http://www.hydrol-earth-syst-sci.net/17/2459/2013/hess-17-2459-2013.pdf
https://vlibrary.iwmi.org/pdf/H045939.pdf
https://vlibrary.iwmi.org/pdf/H045939.pdf
(0.90 MB) (931.98KB)
Coping with water scarcity and growing competition for water among different sectors requires proper water management strategies and decision processes. A prerequisite is a clear understanding of the basin hydrological processes, manageable and unmanageable water flows, the interaction with land use and opportunities to mitigate the negative effects and increase the benefits of water depletion on society. Currently, water professionals do not have a common framework that links depletion to user groups of water and their benefits. The absence of a standard hydrological and water management summary is causing confusion and wrong decisions. The non-availability of water flow data is one of the underpinning reasons for not having operational water accounting systems for river basins in place. In this paper, we introduce Water Accounting Plus (WA+), which is a new framework designed to provide explicit spatial information on water depletion and net withdrawal processes in complex river basins. The influence of land use and landscape evapotranspiration on the water cycle is described explicitly by defining land use groups with common characteristics. WA+presents four sheets including (i) a resource base sheet, (ii) an evapotranspiration sheet, (iii) a productivity sheet, and (iv) a withdrawal sheet. Every sheet encompasses a set of indicators that summarise the overall water resources situation. The impact of external (e.g., climate change) and internal influences (e.g., infrastructure building) can be estimated by studying the changes in theseWA+ indicators. Satellite measurements can be used to acquire a vast amount of required data but is not a precondition for implementingWA+ framework. Data from hydrological models and water allocation models can also be used as inputs to WA+.
14 Karimi, Poolad; Bastiaanssen, W. G. M.; Molden, D.; Cheema, M. J. M. 2013. Basin-wide water accounting based on remote sensing data: an application for the Indus Basin. Hydrology and Earth System Sciences, 17(7):2473-2486. [doi: https://doi.org/10.5194/hess-17-2473-2013]
River basins ; Water accounting ; Indicators ; Groundwater ; Water storage ; Water depletion ; Remote sensing ; Data ; Land use ; Land cover ; Evapotranspiration ; Precipitation ; Biomass / Pakistan / India / China / Afghanistan / Indus Basin
(Location: IWMI HQ Call no: e-copy only Record No: H045940)
http://www.hydrol-earth-syst-sci.net/17/2473/2013/hess-17-2473-2013.pdf
https://vlibrary.iwmi.org/pdf/H045940.pdf
https://vlibrary.iwmi.org/pdf/H045940.pdf
(1.82 MB) (1.84MB)
The paper demonstrates the application of a new water accounting plus (WA+) framework to produce information on depletion of water resources, storage change, and land and water productivity in the Indus basin. It shows how satellite-derived estimates of land use, rainfall, evaporation (E), transpiration (T ), interception (I ) and biomass production can be used in addition to measured basin outflow, for water accounting with WA+. It is demonstrated how the accounting results can be interpreted to identify existing issues and examine solutions for the future. The results for one selected year (2007) showed that total annual water depletion in the basin (501 km3) plus outflows (21 km3) exceeded total precipitation (482 km3). The water storage systems that were effected are groundwater storage (30 km3), surface water storage (9 km3), and glaciers and snow storage (2 km3). Evapotranspiration of rainfall or “landscape ET” was 344 km3 (69% of total depletion). “Incremental ET” due to utilized flow was 157 km3 (31% of total depletion). Agriculture depleted 297 km3, or 59% of the total depletion, of which 85% (254 km3) was through irrigated agriculture and the remaining 15% (44 km3) through rainfed systems. Due to excessive soil evaporation in agricultural areas, half of all water depletion in the basin was non-beneficial. Based on the results of this accounting exercise loss of storage, low beneficial depletion, and low land and water productivity were identified as the main water resources management issues. Future scenarios to address these issues were chosen and their impacts on the Indus Basin water accounts were tested using the new WA+ framework.
15 Srivastava, P. K.; Singh, R. M. 2016. GIS based integrated modelling framework for agricultural canal system simulation and management in Indo-Gangetic plains of India. Agricultural Water Management, 163:37-47. [doi: https://doi.org/10.1016/j.agwat.2015.08.025]
Irrigation systems ; Irrigation canals ; GIS ; Models ; Groundwater management ; Groundwater table ; Water depletion ; Water supply ; Water use efficiency ; Conjunctive use ; Water requirements ; Rainfall-runoff relationships ; Soil moisture ; Intensive farming ; Cropping patterns ; Land use ; Socioeconomic development / India / Uttar Pradesh / Indo-Gangetic Plain
(Location: IWMI HQ Call no: e-copy only Record No: H047740)
(3.11 MB)
Management of canal system for agricultural production is challenging. The work presents GIS based integrated modelling, which integrates soil moisture accounting and irrigation water requirement module, rainfall–runoff module, system loss module and groundwater flow system module. Developed model is employed to evaluate different water management scenarios such as change in rainfall sequence (wet, normal and dry season), change in canal water supply, impact of canal lining and impact of land use changes including their socio–economic implications. The application of model is illustrated with real application in a part of Indo-Gangetic plain of Uttar Pradesh in India. It has been demonstrated that canal water use efficiency in diversion canal systems can be increased up to 58 percent.
16 Pradeleix, L.; Roux, P.; Bouarfa, S.; Jaouani, B.; Lili-Chabaane, Z.; Bellon-Maurel, V. 2015. Environmental impacts of contrasted groundwater pumping systems assessed by life cycle assessment methodology: contribution to the water–energy nexus study. Irrigation and Drainage, 64(1):124-138. [doi: https://doi.org/10.1002/ird.1865]
Groundwater irrigation ; Pumping ; Efficiency ; Environmental impact ; Life cycle assessment ; Groundwater table ; Water depletion ; Tube wells ; Food production ; Energy requirements ; Energy consumption ; Electricity ; Diesel oil ; Greenhouse gases ; Emission ; Case studies / Tunisia / Kairouan
(Location: IWMI HQ Call no: e-copy only Record No: H047751)
(1.69 MB)
Most studies on the environmental performance of irrigation have focused on the water–food–energy nexus, i.e. relationships between food production, water consumption and energy. However, water and energy are not the only relevant indicators of the environmental performance of irrigation systems. Life cycle assessment (LCA) is a holistic method that is well suited to comprehensive assessment. This paper aims at using LCA to assess the environmental impacts of contrasted groundwater pumping systems in semi-arid central Tunisia.
In line with previous studies, our results confirm that for groundwater pumping, energy has the highest environmental impacts on human health, the ecosystem and resource depletion. Our work also highlights that along with pump efficiency, the type of power source must be considered when ranking pumping systems based on environmental performance.
Indeed, diesel-powered pumping systems are more harmful than electric pumps when electricity is generated from natural gas and diesel-powered pump efficiency is low. However, the diesel pumping system becomes the best option when electricity is derived from coal and diesel-powered pump efficiency exceeds 12%.
Finally, water depletion has been shown of great importance in this study, and ongoing LCA improvements should facilitate a more comprehensive picture of these site-specific impacts.
In line with previous studies, our results confirm that for groundwater pumping, energy has the highest environmental impacts on human health, the ecosystem and resource depletion. Our work also highlights that along with pump efficiency, the type of power source must be considered when ranking pumping systems based on environmental performance.
Indeed, diesel-powered pumping systems are more harmful than electric pumps when electricity is generated from natural gas and diesel-powered pump efficiency is low. However, the diesel pumping system becomes the best option when electricity is derived from coal and diesel-powered pump efficiency exceeds 12%.
Finally, water depletion has been shown of great importance in this study, and ongoing LCA improvements should facilitate a more comprehensive picture of these site-specific impacts.
17 Meena, R. P.; Karnam, V.; Tripathi, S. C.; Jha, A.; Sharma, R. K.; Singh, G. P. 2019. Irrigation management strategies in wheat for efficient water use in the regions of depleting water resources. Agricultural Water Management, 214:38-46. [doi: https://doi.org/10.1016/j.agwat.2019.01.001]
Irrigation management ; Strategies ; Water resources ; Water depletion ; Water use efficiency ; Irrigation water ; Wheat ; Crop yield ; Water productivity ; Water deficit ; Climatic data / India / Haryana
(Location: IWMI HQ Call no: e-copy only Record No: H049170)
(0.36 MB)
Wheat is the second most important food crop in India and world. One of the major difficulties faced in the wheat growing regions is the depletion of water resources at an alarming rate. This study was conducted to test the hypothesis that the use of the reduced amount of irrigation water would maintain the grain yield of popular Indian wheat variety HD2967. Water use, crop yield and water use efficiency of wheat were evaluated for three consecutive years under thirteen different irrigation treatments. Highest yield (5372.4 kgha-1 ) was recorded when crop was irrigated with full irrigation (60 mm of water at all five critical crop growth stages); which were statistically at par to yields recorded under 25% deficit irrigation (45 mm) at all growth stages. The treatment with 50% irrigation (30 mm) at all five growth stages although saved 50% water, yield penalty was also significant (4788.1 kgha-1 = 10.9% loss). Treatments with normal recommended practice (60 mm) have achieved lower water use efficiency (WUE) values (1.88 kg m-3) whereas, 25% deficit irrigation i.e. 45 mm at all five stages recorded significantly higher WUE (2.23 kgm-3) in sandy loam soils. The treatment where a total of 750 m3 water was saved per hectare was the most remunerative option in addition to saving of cost on water, electricity and labour. Adoption of 45 mm irrigation at all crop growth stages can enhance both irrigation water use efficiency without any yield penalty and can be adopted as a water saving mechanism in the regions of depleting water resources.
18 Tfwala, C. M.; van Rensburg, L. D.; Bello, Z. A.; Zietsman, P. C. 2019. Transpiration dynamics and water sources for selected indigenous trees under varying soil water content. Agricultural and Forest Meteorology, 275:296-304. [doi: https://doi.org/10.1016/j.agrformet.2019.05.030]
Trees ; Transpiration ; Groundwater ; Water availability ; Soil water content ; Water use ; Water depletion ; Evapotranspiration ; Rain ; Chemicophysical properties ; Arid zones / South Africa / Kolomela Mine
(Location: IWMI HQ Call no: e-copy only Record No: H049326)
(2.17 MB)
The major route through which water from the earth’s surface re-enters the hydrologic cycle in forested ecosystems is via tree transpiration (T). It is therefore important to have detailed understanding of the quantity and source of water transpired by different tree species. The aims of this study were to i) assess the trends of T for selected tree species (camel thorn, sweet thorn, shepherd’s tree and buffalo thorn) across a range of soil water content conditions and ii) partition the total T of the selected tree species growing in arid environments dominated by open cast mining activities into soil water and groundwater. Tree T was measured using the compensation heat pulse velocity (CHPV) method, while soil water content was monitored using DFM capacitance probes. The soil water content within the upper 50 cm soil profile ranged from 11 mm during the dry season to 20 mm during the wet season. The deeper soil layer (50–120 cm) was generally wetter compared to the top layer with water content was up to >30 mm during the wet season. The measured tree T ranged from 0.2 mm day-1 on buffalo thorn during the dry season to 1.9 mm day-1 on sheperd’s tree in summer. It was also revealed that T of large (diameter at breast height =46 cm) camel thorn trees is not responsive to seasonal variations of soil water availability and remained constant at approximately 1.2 mm day-1. Diurnal patterns of T did not effect changes on the soil water depletions within the top 120 cm soil profile, which indicated that the trees sourced water beyond this zone. Signs of daytime redistribution were observed within the canopy areas of the investigated trees during very limited soil water conditions of the dry season. It was concluded that the water use of trees is inclined to the seasonal variations, which however is not the case in old trees. Close to 100% of the water transpired by trees in the study area is sourced below 1.2 m (vadose zone and water table). We recommended investigation of daytime redistribution among the indigenous tree species of the study area. We also recommended extension of tree water use studies to other species for comprehensive catchment tree water use calculations to inform water budgets.
19 Kourakos, G.; Dahlke, H. E.; Harter, T. 2019. Increasing groundwater availability and seasonal base flow through agricultural managed aquifer recharge in an irrigated basin. Water Resources Research, 55(9):7464-7492. [doi: https://doi.org/10.1029/2018WR024019]
Water availability ; Groundwater table ; Agriculture ; Groundwater recharge ; Aquifers ; Water storage ; Water depletion ; Water levels ; Surface water ; Stream flow ; Ecosystems ; Water balance ; Drought ; Models / USA / California / Central Valley
(Location: IWMI HQ Call no: e-copy only Record No: H049452)
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2018WR024019
https://vlibrary.iwmi.org/pdf/H049452.pdf
https://vlibrary.iwmi.org/pdf/H049452.pdf
(7.63 MB) (7.63 MB)
Groundwater aquifers provide an important “insurance” against climate variability. Due to prolonged droughts and/or irrigation demands, groundwater exploitation results in significant groundwater storage depletion. Managed aquifer recharge (MAR) is a promising management practice that intentionally places or retains more water in groundwater aquifers than would otherwise naturally occur. In this study, we examine the possibility of using large irrigated agricultural areas as potential MAR locations (Ag-MAR). Using the California Central Valley Groundwater-Surface Water Simulation Model we tested four different agricultural recharge land distributions, two streamflow diversion locations, eight recharge target amounts, and five recharge timings. These scenarios allowed a systematic evaluation of Ag-MAR on changes in regional, long-term groundwater storage, streamflow, and groundwater levels. The results show that overall availability of stream water for recharge is critical for Ag-MAR systems. If stream water availability is limited, longer recharge periods at lower diversion rates allow diverting larger volumes and more efficient recharge compared to shorter diversion periods with higher rates. The recharged stream water increases both groundwater storage and net groundwater contributions to streamflow. During the first decades of Ag-MAR operation, the diverted water contributed mainly to groundwater storage. After 80 years of Ag-MAR operation about 34% of the overall diverted water remained in groundwater storage while 66% discharged back to streams, enhancing base flow during months with no recharge diversions. Groundwater level rise is shown to vary with the spatial and temporal distribution of Ag-MAR. Overall, Ag-MAR is shown to provide long-term benefits for water availability, in groundwater and in streams.
20 Vij, S.; John. A.; Barua, A. 2019. Whose water? whose profits?: the role of informal water markets in groundwater depletion in peri-urban Hyderabad. Water Policy, 21(5):1081-1095. [doi: https://doi.org/10.2166/wp.2019.129]
Water resources ; Water market ; Informal sector ; Profit ; Groundwater ; Water depletion ; Economic aspects ; Periurban areas ; Farmers ; Villages / India / Hyderabad / Kokapet / Adibatla / Malkaram
(Location: IWMI HQ Call no: e-copy only Record No: H049462)
https://iwaponline.com/wp/article-pdf/21/5/1081/614407/021051081.pdf
https://vlibrary.iwmi.org/pdf/H049462.pdf
https://vlibrary.iwmi.org/pdf/H049462.pdf
(0.36 MB) (372 KB)
Urbanising cities of India are engulfing the peri-urban land and water resources. Informal water sellers, who transfer water from peri-urban to urban areas, meet the growing water demand in Hyderabad, one of the fastest growing cities in India. This article qualitatively explores how informal water tankers are changing the flows of water, posing challenges to water access for peri-urban residents. We conclude that apart from the state's infrastructural and capacity challenges to provide piped water, power interplay between actors is responsible for the mushrooming of informal water markets. The transfer of water has contributed to groundwater depletion as well as to the water insecurity of peri-urban residents.
Powered by DB/Text WebPublisher, from
