• Energy Research

AbstractWhile the world is facing unprecedented transitions and threats we need to deeply rethink the relationships between water and energy use, food production, and ecosystem protection. This includes the development and deployment of ambitious, out‐of‐the‐box solutions towards sustainable development. This paper is based upon recent discussions before and during the 2nd World Irrigation Forum in Chiang Mai, Thailand.This paper takes stock of current knowledge and analyses the most recent trends in water, irrigation and the environment. It discusses the requirements for strategic approaches and the contributions of irrigation and drainage to Sustainable Development Goals. Firstly, we concentrated on renewed and more balanced relationships between water, energy, food and ecosystems in the context of irrigation and drainage management. Secondly, we assessed the positive and negative impact of agricultural water use in order to demonstrate and improve its performance. Given exacerbated competition and water resource scarcity, a better understanding of the positive effects and valuable ecosystem services provided by irrigation and drainage systems could pave the way to maximizing benefits and safeguarding the environment. Lastly, we tried to address the role of stakeholders in irrigation governance. This includes active contribution to policy‐making and planning, incentives, and most importantly, capacity development. Copyright © 2017 John Wiley & Sons, Ltd.

AbstractClimate and catchment characteristics, particularly land and water use and management, may vary according to the population growth rate, future food habits and water demands. Three climate simulations corresponding to the Intergovernmental Panel on Climate Change, Special Report on Emissions Scenarios (A1B) were downscaled using the ‘Providing Regional Climates for Impact Studies’ (PRECIS) for the period 1961–2098, and bias correction was performed using the quantile mapping (QM) method. A semi‐distributed integrated model (Modified Soil and Water Assessment Tool, SWAT) was used to predict the impacts of dynamic changes in catchment characteristics in the Himayat Sagar (HS) catchment and the effects of future climate change on future streamflow and groundwater storage. Simulations predicted that if this trend continues in the future, future climate and anthropogenic changes will lead to a more than 50% reduction in streamflow and a 50% increase in actual evaporation in the HS catchment. This would reduce groundwater storage to a depth of 15 m compared to current conditions, and by the end of the century, there would be no contribution from the base flow to the streamflow. Overall, unless current policies are modified to stabilize land and water management practices, anthropogenic changes will have greater importance than climate change.

AbstractHydrological models are recognized as valid scientific tools to study water quantity and quality and provide support for the integrated management and planning of water resources at different scales. In common with many catchments in the Mediterranean, the study catchment has many problems such as the increasing gap between water demand and supply, water quality deterioration, scarcity of available data, lack of measurements and specific information. The application of hydrological models to investigate hydrological processes in this type of catchments is of particular relevance for water planning strategies to address the possible impact of climate and land use changes on water resources.The distributed catchment scale model (DiCaSM) was selected to study the impact of climate and land use changes on the hydrological cycle and the water balance components in the Apulia region, southern Italy, specifically in the Candelaro catchment (1780 km2). The results obtained from this investigation proved the ability of DiCaSM to quantify the different components of the catchment water balance and to successfully simulate the stream flows. In addition, the model was run with the climate change scenarios for southern Italy, i.e. reduced winter rainfall by 5–10%, reduced summer rainfall by 15–20%, winter temperature rise by 1·25–1·5 °C and summer temperature rise by 1·5–1·75 °C. The results indicated that by 2050, groundwater recharge in the Candelaro catchment would decrease by 21–31% and stream flows by 16–23%. The model results also showed that the projected durum wheat yield up to 2050 is likely to decrease between 2·2% and 10·4% due to the future reduction in rainfall and increase in temperature.In the current study, the reliability of the DiCaSM was assessed when applied to the Candelaro catchment; those parameters that may cause uncertainty in model output were investigated using a generalized likelihood uncertainty estimation (GLUE) methodology. The results showed that DiCaSM provided a small level of uncertainty and subsequently, a higher confidence level. Copyright © 2010 John Wiley & Sons, Ltd.

Abstract The focus of this study was to investigate the impact of climate and land-use changes on water resources and to find suitable drought indices to identify the occurrence, frequency and severity of the past and future drought events. The Ebbw catchment, Wales, UK was selected for this study. Data for the 1961–2012 period were used as input to the DiCaSM model. Following model calibration and validation, the model was run with UKCP09 future climate scenarios for three periods (30 years each) up to 2099 under three emission scenarios. The reconnaissance drought index, the standardized precipitation index, soil moisture deficit and the wetness index were able to reproduce the past drought events. The data of UKCP09, simple change factors to temperature (± °C) and rainfall (%) using Joint Probability plot and daily values of the weather generator were input to the model. The projections indicated that the streamflow and groundwater recharge are likely to increase in winter and to decrease in spring, summer and autumn. Under all emission scenarios, the greatest decrease in groundwater recharge and the streamflow is projected in the 2050s and 2080s under high emission scenario. Moreover, under medium and high emission scenarios, severity and frequency of the drought events are likely to be high. Land use change from grass and/or arable to woodland had significant impact on water resources.

AbstractIn this study, the Distributed Catchment-Scale Model, DiCaSM, was used to study the impact of climate change on the hydrology of the Eden catchment, north east of Scotland. As a first step, the model was successfully calibrated and validated for a 42 years period. The DiCaSM model was then used to study the impact of climate change on the water availability. Data from the UKCP09 Climate change scenarios for the 2010–2039, 2040–2069 and 2070–2099 periods, considering three gas emission scenarios (low, medium and high), were applied. The results indicated that the greatest decrease in streamflow and groundwater recharge was projected to happen under the high emission scenarios towards the end of the century, i.e. between 2070 and 2099. This would mainly be due to the summers becoming drier. Meanwhile, the projected increase in winter precipitation did not contribute much towards groundwater recharge due the projected increases in evapotranspiration and soil moisture deficit.The following drought indices were calculated and were found to be effective in predicting different types of droughts: the Standardized Precipitation Index, SPI, and the Standardized Precipitation Evaporation Index, SPEI, the Reconnaissance Drought Index, RDI, the modified adjusted RDI, the Soil Moisture Deficit, SMD and the Wetness Index, WI. The findings of the study have broader implications in water resources management considering the future changes in climate.

AbstractClimate change (CC) could lead to many crises. Therefore, increasing the number of cultivated varieties represents a low‐cost factor in confronting this problem. The effect of the genotype × environment (G × E) interaction on yield stability was estimated for 28 new sesame lines in the Beni Suwef, El‐Beheira and El‐Menoufia governorates in Egypt across 15 environments from 2019 to 2022 using AMMI analysis. The SALTMED model was used to predict the yield of sesame plants under five increasing air temperature scenarios (CC factor) to obtain future projections of sesame yield to determine the lines that are most genetically stable and facing CC. Variance analysis revealed significant differences in yield between the G and E groups and between the G × E interaction group. Fifteen genotypes yielded better control, and C6.4, C5.8 and C9.6 were selected as genetically stable according to AMMI analysis. The SALTMED model predicted that the yields of lines C3.8 and C6.2 were not affected under the high‐temperature scenarios across the three governorates, moreover lines C1.8, C2.3, and, C6.12 productions were not affected under Beni Suwef and El‐Beheira governorates. of lines C1.8, C2.3 and C6.12 were also not affected by the Beni Suwef or El‐Beheira governorates. It is now possible to establish a hybridization programme in sesame that combines parents with high productivity and high resilience to CC.

AbstractThe integrated hydrological modelling system, IHMS, has been described in detail in Part 1 of this paper. The system comprises three models: Distributed Catchment Scale Model (DiCaSM), MODFLOW (v96 and v2000) and SWI. The DiCaSM simulates different components of the unsaturated zone water balance, including groundwater recharge. The recharge output from DiCaSM is used as input to the saturated zone model MODFLOW, which subsequently calculates groundwater flows and head distributions. The main objectives of this paper are: (1) to show the way more accurate predictions of groundwater levels in two Cyprus catchments can be obtained using improved estimates of groundwater recharge from the catchment water balance, and (2) to demonstrate the interface utility that simulates communication between unsaturated and saturated zone models and allows the transmission of data between the two models at the required spatial and temporal scales. The linked models can be used to predict the impact of future climate change on surface and groundwater resources and to estimate the future water supply shortfall in the island up to 2050. The DiCaSM unsaturated zone model was successfully calibrated and validated against stream flows with reasonable values for goodness of fit as shown by the Nash‐Sutcliffe criterion. Groundwater recharge obtained from the successful tests was applied at various spatial and temporal scales to the Kouris and Akrotiri catchments in Cyprus. These recharge values produced good estimates of groundwater levels in both catchments. Once calibrated, the model was run using a number of possible future climate change scenarios. The results showed that by 2050, groundwater and surface water supplies would decrease by 35% and 24% for Kouris and 20% and 17% for Akrotiri, respectively. The gap between water supply and demand showed a linear increase with time. The results suggest that IHMS can be used as an effective tool for water authorities and decision makers to help balance demand and supply on the island. Copyright © 2010 John Wiley & Sons, Ltd.

AbstractThe clearest signs of hydrologic change can be observed from the trends in streamflow and groundwater levels in a catchment. During 1980–2007, significant declines in streamflow (−3.03 mm/year) and groundwater levels (−0.22 m/year) were observed in Himayat Sagar (HS) catchment, India. We examined the degree to which hydrologic changes observed in the HS catchment can be attributed to various internal and external drivers of change (climatic and anthropogenic changes). This study used an investigative approach to attribute hydrologic changes. First, it involves to develop a model and test its ability to predict hydrologic trends in a catchment that has undergone significant changes. Second, it examines the relative importance of different causes of change on the hydrologic response. The analysis was carried out using Modified Soil and Water Assessment Tool (SWAT), a semi‐distributed rainfall‐runoff model coupled with a lumped groundwater model for each sub‐ catchment. The model results indicated that the decline in potential evapotranspiration (PET) appears to be partially offset by a significant response to changes in rainfall. Measures that enhance recharge, such as watershed hydrological structures, have had limited success in terms of reducing impacts on the catchment‐scale water balance. Groundwater storage has declined at a rate of 5 mm/y due to impact of land use changes and this was replaced by a net addition of 2 mm/y by hydrological structures. The impact of land use change on streamflow is an order of magnitude larger than the impact of hydrological structures and about is 2.5 times higher in terms of groundwater impact. Model results indicate that both exogenous and endogenous changes can have large impacts on catchment hydrology and should be considered together. The proposed comprehensive framework and approach demonstrated here is valuable in attributing trends in streamflow and groundwater levels to catchment climatic and anthropogenic changes.