توصيفگر ها :
تحليل سناريو , ريسك , تغييراقليم(گزارش ششم) , LARS-WG , HEC-HMS , WEAP
چكيده انگليسي :
Comprehensive water resources planning and management, considering all water sources (surface and groundwater) and uses (drinking, sanitation, agriculture, industry, and environment) with the aim of sustainable development and risk reduction, significantly improves water resource conditions. In recent decades, climatic and management issues have severely reduced water resources, leading to serious threats such as air pollution, land subsidence, and declining water quality. The Zayandeh-Rud basin, part of the Gavkhouni watershed in central Iran, is crucial due to its central location and the presence of major industries such as steel, petrochemicals, and refineries. The basin's complexity, arising from various hydrological and climatic conditions, inter-basin water transfers, and interactions between surface and groundwater, necessitates thorough research on its sustainability.This study aims to analyze water resources and demands in the Zayandeh-Rud basin under various management and climate scenarios, using existing data and studies. Climate change impacts were assessed using the sixth assessment report and three scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5), with SSP2-4.5 being selected for further analysis. The LARS-WG model was employed to predict temperature and precipitation in the basin's upper regions, demonstrating high accuracy. Runoff for two major sub-basins (Ghaleh-Shahrokh and Eskandari) was calculated using the HEC-HMS model based on predicted climatic variables, and this runoff was directed to downstream uses.Using the WEAP model, water management scenarios were developed through September 2021. Four scenarios were analyzed: 1) Continuation of current trends, 2) Supply management (including inter-basin transfers like the Oman Sea and Mandegan projects), 3) Demand management (16% reduction in domestic, 10% in industrial, and 20% in agricultural water use), and 4) Combined supply and demand management. Performance metrics (reliability in time and volume, resilience, vulnerability, and maximum deficit), sustainability index, and risk were evaluated for each scenario over a five-year period (October 2025 to September 2030).Simulation results indicated that the combined scenario achieved a sustainability rate of 99.93% in meeting demands with nearly zero risk. Conversely, the continuation scenario showed the basin's water resources in a critical state. Groundwater resources, comprising 13 active aquifers, demonstrated weak sustainability (25%) and a risk level of approximately 16% under the combined scenario. Although significant recovery in aquifers is unlikely over the five-year period, long-term implementation of these policies may yield better outcomes. Surface water resources, specifically the Zayandeh-Rud reservoir, showed severe volume declines but improved under the supply management scenario, achieving 43% sustainability and 29% risk under the combined scenario, with the reservoir fully replenished by the end of the period.The study concludes that integrated supply and demand management is essential for improving and preserving the basin's deteriorating water resources.
