Your search found 42 records
(Location: IWMI HQ Call no: P 7911 Record No: H040156)
(Location: IWMI HQ Call no: IWMI 631.7.2 G514 DEC Record No: H041486)
(Location: IWMI HQ Call no: IWMI 631.7.2 G514 DEC Record No: H041634)
4 Teixeira, A. H. de. C. 2008. Measurements and modelling of evapotranspiration to assess agricultural water productivity in basins with changing land use patterns: a case study in the Sao Francisco River Basin, Brazil. PhD thesis partly funded by IWMI's Capacity Building Project. Wageningen, Netherlands: Wageningen University; Enschede, Netherlands: International Institute for Geo-Information Science and Earth Observation (ITC). 233p. (ITC Dissertation 156)
(Location: IWMI HQ Call no: D 631.7.2 G514 TEI Record No: H041666)
(Location: IWMI HQ Call no: e-copy only Record No: H041668)
(1.64 MB)
(Location: IWMI HQ Call no: e-copy only Record No: H041667)
(1.51 MB)
(Location: IWMI HQ Call no: e-copy only Record No: H041814)
8 Senay, G. B.; Budde, M. E.; Verdin, J. P.; Rowland, J. 2009. Estimating actual evapotranspiration from irrigated fields using a simplified surface energy balance approach. In Thenkabail, P. S.; Lyon, J. G.; Turral, H.; Biradar, C. M. (Eds.). Remote sensing of global croplands for food security. Boca Raton, FL, USA: CRC Press. pp.317-329. (Taylor & Francis Series in Remote Sensing Applications)
(Location: IWMI HQ Call no: 631.7.1 G000 THE Record No: H042428)
9 Ahmad, Mobin-ud-Din; Turral, H.; Nazeer, Aamir; Hussain, Asghar. 2009. Satellite-based assessment of agricultural water consumption, irrigation performance, and water productivity in a large irrigation system in Pakistan. In Thenkabail, P. S.; Lyon, J. G.; Turral, H.; Biradar, C. M. (Eds.). Remote sensing of global croplands for food security. Boca Raton, FL, USA: CRC Press. pp.331-354. (Taylor & Francis Series in Remote Sensing Applications)
(Location: IWMI HQ Call no: 631.7.1 G000 THE Record No: H042429)
(1.08 MB)
10 Teixeira, A. H. de. C. 2008. Measurements and modelling of evapotranspiration to assess agricultural water productivity in basins with changing land use patterns: a case study in the Sao Francisco River Basin, Brazil. [PhD thesis partly funded by IWMI's Capacity Building Project]. Wageningen, Netherlands: Wageningen University; Enschede, Netherlands: International Institute for Geo-Information Science and Earth Observation (ITC) 233p. (ITC Dissertation 156)
(Location: IWMI HQ Call no: D 631.7.2 G514 TEI c2 Record No: H042995)
11 Hillel, D. 1982. Introduction to soil physics. London, UK: Academic Press. 364p.
(Location: IWMI HQ Call no: 631.4 G000 HIL Record No: H043951)
(0.48 MB)
12 Chemin, Yann. 2012. A distributed benchmarking framework for actual ET models. In Irmak, A. (Ed.). Evapotranspiration - remote sensing and modeling. Rijeka, Croatia: InTech. pp.421-436.
(Location: IWMI HQ Call no: e-copy only Record No: H044675)
(0.29 MB) (300.42KB)
With the various types of actual ET models being developed in the last 20 years, it becomes necessary to inter-compare methods. Most of already published ETa models comparisons address few number of models, and small to medium areas (Chemin et al., 2010; Gao & Long, 2008; García et al., 2007; Suleiman et al., 2008; Timmermans et al., 2007). With the large amount of remote sensing data covering the Earth, and the daily information available for the past ten years (i.e. Aqua/Terra-MODIS) for each pixel location, it becomes paramount to have a more complete comparison, in space and time. To address this new experimental requirement, a distributed computing framework was designed, and created. The design architecture was built from original satellite datasets to various levels of processing until reaching the requirement of various ETa models input dataset. Each input product is computed once and reused in all ETa models requiring such input. This permits standardization of inputs as much as possible to zero-in variations of models to the models internals/specificities.
(Location: IWMI HQ Call no: 621.3678 G000 WAR Record No: H045035)
(0.46 MB)
14 Kogan, F.; Powell, A. M. Jr.; Fedorov, O. (Eds.) 2009. Use of satellite and In-Situ data to improve sustainability: Proceedings of the NATO Advanced Research Workshop on Using Satellite Data and In-Situ Data to Improve Sustainability, Kiev, Ukraine, 9-12 June 2009. 313p. (NATO Science for Peace and Security Series - C: Environmental Security)
(Location: IWMI HQ Call no: 384.51 G000 KOG Record No: H046311)
(0.46 MB)
15 Petropoulos, G. P. 2014. Remote sensing of energy fluxes and soil moisture content. Boca Raton, FL, USA: CRC Press. 506p.
(Location: IWMI HQ Call no: 551.52530287 G000 PET Record No: H046471)
(0.44 MB)
(Location: IWMI HQ Call no: e-copy only Record No: H046715)
(4.92 MB)
The Lower Chenab canal irrigation scheme, the largest irrigation scheme of the Indus Basin irrigation system was selected for an estimate of groundwater recharge using the soil and water assessment tool (SWAT) at high spatial and temporal resolution under changing climate. Groundwater recharge was simulated using the SWAT model for representative concentration pathways (RCP) 4.5 and 8.5 climate change scenarios for the period 2012–2020. Actual evapotranspiration (ETa) was estimated using the SWAT model for the period 2010–2011. This was compared with the ETa determined using the surface energy balance algorithm (SEBAL) calibrated using data for the period 2005–2009. We concluded that the SWAT ETa estimates showed good agreement with those of SEBAL (coefficient of determination = 0.85 ± 0.05, Nash–Sutcliffe efficiency = 0.83 ± 0.07). The total average annual groundwater recharge to the aquifer was 537 mm (±55 mm) with the maximum occurring during July (151 mm). The results showed that groundwater recharge would increase by 40%, as compared to the reference period, by the end of 2020 under RCP 4.5 and by 37% under RCP 8.5. The SWAT can thus be a handy tool for not only estimating the recharge at high spatial and temporal resolution, but also under changing climate.
(Location: IWMI HQ Call no: e-copy only Record No: H047849)
(4.67 MB)
A remote sensing based geo-informatics approach was developed to estimate water resources management (WRM) components across a large irrigation scheme in the Indus Basin of Pakistan. The approach provides a generalized framework for estimating a range of key water management variables and provides a management tool for the sustainable operation of similar schemes globally. A focus on the use of satellite data allowed for the quantification of relationships across a range of spatial and temporal scales. Variables including actual and crop evapotranspiration, net and gross irrigation, net and gross groundwater use, groundwater recharge, net groundwater recharge, were estimated and then their interrelationships explored across the Hakra Canal command area. Spatially distributed remotely sensed estimates of actual evapotranspiration (ETa) rates were determined using the Surface Energy Balance System (SEBS) model and evaluated against ground-based evaporation calculated from the advection-aridity method. Analysis of ETa simulations across two cropping season, referred to as Kharif and Rabi, yielded Pearson correlation (R) values of 0.69 and 0.84, Nash-Sutcliffe criterion (NSE) of 0.28 and 0.63, percentage bias of -3.85% and 10.6% and root mean squared error (RMSE) of 10.6 mm and 12.21 mm for each season, respectively. For the period of study between 2008 and 2014, it was estimated that an average of 0.63 mm day-1 water was supplied through canal irrigation against a crop water demand of 3.81 mm day-1. Approximately 1.86 mm day-1 groundwater abstraction was estimated in the region, which contributed to fulfil the gap between crop water demand and canal water supply. Importantly, the combined canal, groundwater and rainfall sources of water only met 70% of the crop water requirements. As such, the difference between recharge and discharge showed that groundwater depletion was around -115 mm year-1 during the six year study period. Analysis indicated that monthly changes in ETa were strongly correlated (R = 0.94) with groundwater abstraction and rainfall, with the strength of this relationship significantly (p < 0.01 and 0.05) impacted by cropping seasons and land use practices. Similarly, the net groundwater recharge showed a good positive correlation (R) of 0.72 with rainfall during Kharif, and a correlation of 0.75 with canal irrigation during Rabi, at a significance level of p < 0.01. Overall, the results provide insight into the interrelationships between key WRM components and the variation of these through time, offering information to improve the management and strategic planning of available water resources in this region.
18 Kiptala, J. K. 2016. Managing basin interdependencies in a heterogeneous, highly utilized and data scarce river basin in semi-arid Africa: the case of the Pangani River Basin, eastern Africa. PhD thesis. Leiden, Netherlands: CRC Press - Balkema. 174p.
(Location: IWMI HQ Call no: 333.91 G132 KIP Record No: H047471)
(10 MB)
(Location: IWMI HQ Call no: e-copy only Record No: H048431)
(5.79 MB)
This study proposes a novel monitoring tool based on Satellite Remote Sensing (SRS) data to examine the status of water distribution and Water Use Efficiency (WUE) under changing water policies in large-scale and complex irrigation schemes. The aim is to improve our understanding of the water-food nexus in such schemes. With a special reference to the Gezira Irrigation Scheme (GeIS) in Sudan during the period 2000–2014, the tool devised herein is well suited for cases where validation data are absent. First, it introduces an index, referred to as the Crop Water Consumption Index (CWCI), to assess the efficiency of water policies. The index is defined as the ratio of actual evapotranspiration (ETa) over agricultural areas to total ETa for the whole scheme where ETa is estimated using the Simplified Surface Energy Balance model (SSEB). Second, the tool uses integrated Normalized Difference Vegetation Index (iNDVI), as a proxy for crop productivity, and ETa to assess the WUE. Third, the tool uses SSEB ETa and NDVI in an attempt to detect wastage of water. Four key results emerged from this research as follows: 1) the WUE has not improved despite the changing agricultural and water policies, 2) the seasonal ETa can be used to detect the drier areas of GeIS, i.e. areas with poor irrigation water supply, 3) the decreasing trends of CWCI, slope of iNDVI-ETa linear regression and iNDVI are indicative of inefficient utilization of irrigation water in the scheme, and 4) it is possible to use SSEB ETa and NDVI to identify channels with spillover problems and detect wastage of rainwater that is not used as a source for irrigation. In conclusion, the innovative tool developed herein has provided important information on the efficiency of a large-scale irrigation scheme to help rationalize laborious water management processes and increase productivity.
(Location: IWMI HQ Call no: e-copy only Record No: H048899)
(5.36 MB)
The annual water loss through evapotranspiration (ET) is an uncertain but significant component of India’s water budget. The present study generated independent estimates of baseline annual ET, calibrated with in situ micrometeorological data over Indian sub-continent, using surface energy balance framework and satellite-based long-term thermal remote sensing, visible and near-infrared observations as the primary data sources. Thirty years’ (1981–2010) of satellite-based ET estimates at 0.08° grid resolution were used to assess trend in regional ET, to find out change hot-spots and probable causes. Long-term collateral data, influencing ET, such as gridded (0.5° × 0.5°) annual rainfall (RF), annual mean surface soil moisture (SSM) at 25 km resolution from ESA scatterometers and annual mean incoming shortwave radiation from MERRA-2D reanalysis were also analyzed. Mean annual ET loss was found to be the highest for Indian cropland (890 Cubic Km) than forest (575 Cubic Km). Annual water consumption pattern over vegetation systems showed declining ET trend at the rate of -16 Cubic Km yr-1 upto 1995 during 30 years which might be due to declining rainfall and solar dimming. This was followed by increasing ET trend (34 Cubic Km yr-1 ). During 2001–2010, irrigated cropland showed a steep increase in water consumption pattern with an average rate of 4 Cubic Km yr-1 while grassland and forest showed declining consumption patterns since 2003 and 2007, respectively thus showing crossover points of their consumption patterns with irrigated cropland. Four agriculturally important Indian eastern, central, western and southern states showed significantly increasing ET trend with S-score of 15–25 and Z-score of 1.09–2.9 during this period. Increasing ET in western and southern states was found to be coupled with increase in annual rainfall and SSM. But in eastern and central states, no significant trend in rainfall was observed though significant increase in ET was noticed. Region-specific correlation of annual ET with natural forcing variables was higher for incoming shortwave radiation as compared to rainfall. The increase in ET over irrigated croplands as well as over some of the Indian states could be due to increase in anthropogenic factors which need more detailed investigations in future.
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