Integrated management of water resource systems under changing water availability, policy, and irrigation expansion plans

Conventional water resource management has been based on the assumption of stationarity in the characteristics of the water resource systems. However, the validity of this assumption is questionable due to changing climate and increasing human activities. The current level of uncertainty inherent in the projection of future natural and anthropogenic conditions has also complicated water resource planning and management. As a result, there is a fundamental need to acknowledge the uncertainty associated with water resource systems and propose improved management schemes under uncertainty. This thesis presents three developments to assist in understanding system behavior under historical and changing conditions, and to propose an alternative framework for decision making under uncertain conditions. The three parts are put together and applied to the Saskatchewan River Basin (SaskRB) in Saskatchewan, which is a strategically important water resource system in western Canada. In brief, first a Sustainability-oriented Water allocation, Management, and Planning (SWAMPSK) model is developed using the System Dynamics approach. This water resource model captures the causal relationships among system components and combines various aspects of the water resource system, such as water allocation, irrigation demand, and economic evaluation within an integrated system. Second, SWAMPSK is used to map the vulnerability and sectorial trade-offs in the SaskRB in Saskatchewan under changing water availability and irrigation expansion. Using a bottom-up approach, a wide range of streamflow conditions is stochastically generated to accommodate likely scenarios of change in water availability. The streamflow ensemble and alternative irrigation expansion scenarios are used in SWAMPSK for evaluating the water resource system’s performance under potential changes in natural conditions and irrigated areas. Third, an innovative probabilistic framework is proposed to evaluate the risk in system behavior under changing conditions and to identify the contributions of various changing conditions on the overall system performance. For this purpose, the empirical probability distributions of system performance are used to quantify the individual and joint impacts of changing conditions on the system performance with the goal of proposing policies that minimize the risk of undesired changes in system. This thesis provides a set of new and strategically-important insights to the water resource system in Saskatchewan. In brief, increase in irrigation area can raise the total economic benefit except in extremely dry flow conditions, but with some cost of decreasing water availability in downstream regions. Saskatchewan can meet the inter-provincial commitment under changes in flow regime and irrigation expansion. Results also show that no one specific policy can provide the optimal option for water resource management under all changing flow and irrigation expansion conditions and the joint impacts of changing water availability, policy, and irrigation expansion are complex nonlinear functions of individual drivers. This thesis also offers a set of new modeling tools that can be used to assist decision making under uncertainty. In particular, the proposed risk-based framework allows an explicit understanding of the variations in the system performance as a result of changing natural and/or anthropogenic conditions and can be transferred to decision making applications

CHANGE IN FREQUENCY OF ACUTE AND SUBACUTE EFFECTS OF ECSTASY IN A GROUP OF NOVICE USERS AFTER 6 MONTHS OF REGULAR USE

Background: Recent research trends are to specify the relation between patterns of ecstasy use and side effects, possibility of dependency, tolerance and long term neurocognitive damage. The objective of this study was to assess the impact of regular ecstasy use on its acute and subacute effects. Subjects and methods: At the first stage, we recruited 120 subjects. If participants continued regular use of ecstasy in this period, they were asked to participate in the second stage of the research 6 months later. Thirty-five subjects attended the second stage of the study, 5 of which were excluded because they had less than 5 drug experiences during the last 6 months. At last, we recruited 30 novice ecstasy users by means of the snowball technique in Tehran, Iran. The pattern of use and experienced effects of ecstasy was documented at the beginning and after 6 months of regular consumption with a self administered questionnaire. Results: Little or no change was observed in acute effects. Those subacute effects that had considerable increase in frequency were anxiety, depression, aggression, memory impairment, poor concentration and learning problems. Conclusion: Small change in acute effects suggests low possibility of tolerance after at least 6 months of regular use. Our results support long term neurocognitive damage and mood impairment with ecstasy use

Climate change or irrigated agriculture – what drives the water level decline of Lake Urmia

Lake Urmia is one of the largest hypersaline lakes on earth with a unique biodiversity. Over the past two decades the lake water level declined dramatically, threatening the functionality of the lake’s ecosystems. There is a controversial debate about the reasons for this decline, with either mismanagement of the water resources, or climatic changes assumed to be the main cause. In this study we quantified the water budget components of Lake Urmia and analyzed their temporal evolution and interplay over the last five decades. With this we can show that variations of Lake Urmia’s water level during the analyzed period were mainly triggered by climatic changes. However, under the current climatic conditions agricultural water extraction volumes are significant compared to the remaining surface water inflow volumes. Changes in agricultural water withdrawal would have a significant impact on the lake volume and could either stabilize the lake, or lead to its complete collapse

Climate-informed environmental inflows to revive a drying lake facing meteorological and anthropogenic droughts

The rapid shrinkage of Lake Urmia, one of the world\u27s largest saline lakes located in northwestern Iran, is a tragic wake-up call to revisit the principles of water resources management based on the socio-economic and environmental dimensions of sustainable development. The overarching goal of this paper is to set a framework for deriving dynamic, climate-informed environmental inflows for drying lakes considering both meteorological/climatic and anthropogenic conditions. We report on the compounding effects of meteorological drought and unsustainable water resource management that contributed to Lake Urmia\u27s contemporary environmental catastrophe. Using rich datasets of hydrologic attributes, water demands and withdrawals, as well as water management infrastructure (i.e. reservoir capacity and operating policies), we provide a quantitative assessment of the basin\u27s water resources, demonstrating that Lake Urmia reached a tipping point in the early 2000s. The lake level failed to rebound to its designated ecological threshold (1274 m above sea level) during a relatively normal hydro-period immediately after the drought of record (1998–2002). The collapse was caused by a marked overshoot of the basin\u27s hydrologic capacity due to growing anthropogenic drought in the face of extreme climatological stressors. We offer a dynamic environmental inflow plan for different climate conditions (dry, wet and near normal), combined with three representative water withdrawal scenarios. Assuming effective implementation of the proposed 40% reduction in the current water withdrawals, the required environmental inflows range from 2900 million cubic meters per year (mcm yr−1) during dry conditions to 5400 mcm yr−1 during wet periods with the average being 4100 mcm yr−1. Finally, for different environmental inflow scenarios, we estimate the expected recovery time for re-establishing the ecological level of Lake Urmia

Trade-Offs between Human and Environment: Challenges for Regional Water Management under Changing Conditions

Water resource systems are under unprecedented pressure mainly due to rapid socio-economic growth, weak water and land management decisions, as well as variability and change in climate conditions. These pressures have disrupted the functionality of freshwater ecosystems and have generated water management challenges in various regions across the globe. Here, we showcase the potential trade-offs in the Province of Saskatchewan, Canada, between upstream human activities and downstream environmental needs under changing water availability conditions. We showed that an increase in irrigation areas can boost provincial economy but alter timing, magnitude and rhythmicity of the peak flows reaching downstream ecosystems. This indicates that the business as usual management might not be able to handle such emerging challenges. To improve water management, we argue that there is a need to better represent the dynamic interactions between human water use and water quantity and quality conditions and their influence on ecosystems. In addition, impact assessment frameworks need to be improved to better identify system vulnerabilities under changing natural and anthropogenic conditions. Moreover, due to the key role of stakeholders in adopting land and water management decisions, their viewpoints need to be understood and included in management decisions

Evaluating Climate Change Effects on a Snow-Dominant Watershed: A Multi-Model Hydrological Investigation

Assessing the impact of climate change on water systems often requires employing a hydrological model to estimate streamflow. However, the choice of hydrological model, process representation, input data resolution, and catchment discretization can potentially influence such analyses. This study aims to evaluate the sensitivity of climate change impact assessments to various hydrological modeling configurations in a snow-dominated headwater system in Alberta, Canada. The HBV-MTL and GR4J models, coupled with the Degree-Day and CemaNeige snowmelt modules, were utilized and calibrated using point- and grid-based climate data on lumped and semi-distributed catchment discretization. The hydrological models, in conjunction with a water allocation model, were supplied with climate model outputs to project changes in the basin. While all models revealed a unanimous increase in peak flow, the difference between their estimations could be as substantial as 42%. In contrast, their divergence was minimal in projecting median flow. Furthermore, most models projected an aggravated water supply deficit between 16% and 40%. Overall, the quantified climate change impacts were the most sensitive to the choice of snow routine module, followed by the model type, catchment discretization, and data resolution in this snow-dominant basin. Therefore, particular attention should be given to the proper representation of snowmelt processes